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Attic insulation/remodel question

Posted by newbie007 (My Page) on
Mon, Jun 17, 13 at 11:36

I have an old English bungalow from the 1950's in Chicago. The attic is finished and doesn't have enough insulation. So its pretty hot in the summer and cold in winters, boosting my energy bills higher. Here are the list of things we like to do:
1) Get blown in cellulose insulation with estimated R-value of R49, R55 before settling.
2) The attic currently has wood paneling and my wife and I don't like it and like to replace the wood paneling with drywall.
3) We also want to expand the attic in future (2-3 years as we can't afford it now) by adding shed dormers along the length of the house.
Now my confusion is what is the order we need to get these things done in order to minimize or eliminate wastage of work. Please help us decide. Thanks!!


Follow-Up Postings:

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RE: Attic insulation/remodel question

Post this on the remodeling forum. You will get more responses. Mention it is a cross posting.

EnergyRater from Louisiana will give you the inside info.


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RE: Attic insulation/remodel question

Thanks SouthernCanuck, I just posted it in the Remodel forum.


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RE: Attic insulation/remodel question

You need to visit your local codes and permits office. From them you will find out the legal head height required for the bedroom, as well as the required floor space and window size. Then, you need to learn what the insulation requirements are. A lot has changed in the past few years, and in many locations, to get the space insulated properly will require spray foam, or will require more head height than currently exists, so you would need to "pop the top" to make it work.

Once you find out all of that information, then you can plan how to approach the projects.


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RE: Attic insulation/remodel question

Thank you GreenDesigns


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RE: Attic insulation/remodel question

Regardless of what the codes are now, if you do major work up there, you will have to update it all rather than let it be. I am assuming from the picture, that this is a 1 1/2 storey house? Looks like the upstairs of a friend's place like that.

If you are going to do dormers, then the proper thing is to hold off on anything until you have the money to do them; if you aren't using the space currently, then you could remove the paneling and use spray-foam on the walls which won't be altered. One thing: I think that those R values are a bit higher than needed even for Chicago. :) Using cellulose, I don't think you can get those values in normal depth stud bays, but I may be wrong on that.

If you aren't going to use the space, then close the heat and air off up there to save the money until the dormers are done. In either case, research the Code and Permit people, and see what insulation will give what you want--I just don't think blown in cellulose (which my walls have) or poly sheathing will give it.

Any work you do now will just be wasted once you start on the dormers, so why open that can of worms until necessary?


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RE: Attic insulation/remodel question

What is the attic venting like?

There are a couple of different approaches depending on how you approach the insulation and how the attic is or is not vented.


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RE: Attic insulation/remodel question

I think I have a couple of roof vents. Does that make my attic vented? I also dropped my plans to get dormers. So I would like to ask the question on insulation. I had a couple of contractors come out and give me estimates on insulation. I am really not open to tearing open the wood panels down to studs - so I think foam insulation is not an option.
Contractor 2 performed blower test and recommended CELLULOSE INSULATION and AIR SEALING. Please advise me if their recommendations are good and if their price is fair. My house is a 1.5 story 1500 S.F living space

The scope of the work to include the following:

1) Attic insulation and Air sealing: $3250 (My Attic is finished. see pic)
Access attic trough knee walls: staple netting to hold the insulation in place
Walls: Insulation with blow-in cellulose eves to the full capacity and walls.
Floor : remove necessary boards and blow-in insulation.
Ceiling space: Blow in 12 to 14 inches of new Cellulose insulation over existing insulation. Total fill level of 15 inches. Total estimated R-Value of R49, R55 before settling.
Insulation and weather stripping knee walls with Easy Touch Cotton Insulation.
Confirm that attic has adequate ventilation.
Air sealing Attic with closed cell foam all bypasses from the house to the attic (light fixtures, can lights, exhaust fans etc.)

2) Air seal interior $500 (this is the first/main level):
Weather strip doors, caulking around baseboard, trim, windows.

3) Dining room $800 (This room is an addition in 1970's. The exterior is siding. Insulation is for Ceiling and 3 walls)
Cut opening to access ceiling space (no repairs) and blow-in cellulose insulation R49. Install baffles for soffits if necessary for proper ventilation. Cut opening in the walls and blow in cellulose

4) Basement rim joist insulation $750 (Basement is unfinished)
All accessible rim joist insulation with rigid foam board and spray foam


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RE: Attic insulation/remodel question

@ columbusguy, thanks for your feedback.


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RE: Attic insulation/remodel question

I forgot to mention that contractor-2 will work with peoples gas and get me $1750 instant rebate. So final quote is $3250 attic+ $500 airseal mainlevel + $800 addition room + $750 basement ceiling - $1750 instant rebate = $3550 and my house will also be eligible for an Illinois Home Performance with ENERGY STAR® certificate


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RE: Attic insulation/remodel question

Where is energy rater when you need her. Newbie she is the perfecto expert for your question here. I haven't seen a post from her in a while. I hope all is well with her. Look up her profile page by entering her name in the search engine top right of the page and select email on her profile page.

energy_rater_la


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RE: Attic insulation/remodel question

While do rudimentary research for adding wall insulation, I came across some very insightful information advocating against adding insulation to existing homes.

As I recall, essentially it promoted only air sealing. Aside from additional cost, the problem is that added insulation inevitably caused moisture/mold issues.

In new homes, both the interior/exterior are moisture barriered. When adding insulation to an older home, depending how it's applied, either only the interior is barriered or no barrier is added at all...either way wall cavity ventilation is reduced because of infill, and moisture eventually permeates.

Interior air sealing creates a controlled air environment, and still allows for wall cavity breathability while significantly reducing heating/cooling bills; whereas both interior/exterior air sealing cause the walls to act somewhat like a double-paned window because of the dead airspace within.

Since you already have to do it, just seal the interior and insulate windows/doors...seal the exterior. Then add heavy curtains flush with the wall, and full length heat reducing window screens (not tint).

For comparison, last winter I caulked two drafty windows, and a wall air conditioner frame. I also insulated the front door and replaced the drafty threshold seal. Regardless of the many remaining air leaks that await sealing, there was a significant change in how less cold the house was. Also, just from those few changes, this summer my electricity bill is one-third less despite running the air conditioner all day/night...last summer I turned it off whenever we weren't home, but now I leave my dogs inside when we're gone so it's constantly on.

I have many home projects ahead, but adding insulation is definitely not one. I think you'll be pleasantly surprised how efficient your home becomes by air sealing alone. For an unbiased opinion, check if your power company offers free energy audits. It may not be economically efficient to try for the highest r-value rating, by applying that money toward more energy efficient appliances you might come out ahead financially, especially if your power company has energy efficient appliance rebates.


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RE: Attic insulation/remodel question

PS: In case you're unfamiliar with them, take a look at these window insulating ideas http://energy.gov/energysaver/articles/energy-efficient-window-treatments

In my post above, I said not tint, because of both the thermal shock of mirrored tint, and screens can be removed for winter.


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RE: Attic insulation/remodel question

Okay, retrying link addition.

Here is a link that might be useful: Dept. of Energy, Energy Saver


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RE: Attic insulation/remodel question

got your email southerncanuck...will reply back
later today when I have more time...now that I've
found the thread.

I see more info here newbie...so will reply to
this thread.


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RE: Attic insulation/remodel question

SouthernCanuck, pecospaul and energy rater, thank you so much for your responses. The more and more I know about insulation/ductwork/HVAC/energy efficiency combo, the more I get confused. Isn't ignorance bliss? I will eagerly wait to hear more from energy rater. I am also replacing my 36 year old furnace and ductwork. This itself is a separate topic. The HVAC guy took some measurements and will be doing a load calc and getting back to me with his recommendations. So it is going to be a big project. I don't mind doing all the improvements. I would like to do them right, the first time. Thanks for all your help experts!


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RE: Attic insulation/remodel question

Newbie, the cavalry has arrived and she is Energy Rater from the great state of Louisiana. She is the woman with the plan, you can take that to the bank.


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RE: Attic insulation/remodel question

SouthernCanuck, pecospaul and energy rater, thank you so much for your responses. The more and more I know about insulation/ductwork/HVAC/energy efficiency combo, the more I get confused. Isn't ignorance bliss? I will eagerly wait to hear more from energy rater. I am also replacing my 36 year old furnace and ductwork. This itself is a separate topic. The HVAC guy took some measurements and will be doing a load calc and getting back to me with his recommendations. So it is going to be a big project. I don't mind doing all the improvements. I would like to do them right, the first time. Thanks for all your help experts!


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RE: Attic insulation/remodel question

your biggest savings is in first reducing air leakage, then
insulating.

paneling has a lot of air leakage. once you sheetrock, & have
everything taped & floated it will solve the bulk of the
air intrusion.. then it is the sole plate where it is attached to
the floor that needs to be caulked, and each penetration into
walls & ceilings.
use a fire rated caulk for electrical, and regular caulk
with long life for the rest. I like dap's alex 35 year
caulk that goes on white & dries clear.

what you need to understand about areas like this is
that they are surrounded by extreme attic temps on sides,
top and bottom. we build exterior walls for ambient temps
insulate and air/water seal them...but in the attic
putting batts or bibs is the norm.
while it insulates the walls...this does nothing for air sealing
or temp gains from extreme attic.

if instead the walls were air sealed & had a surface that would
reflect heat out of walls...then you'd have comfort you can
afford to maintain in these rooms.

here is a link to an air sealing pdf by southface inst.
look at the detail on page 5.
http://www.southface.org/default-interior/Documents/airsealingkeypoints.p df
while the configuration is different...this is what your dormer
rooms are, from an air/thermal barrier perspective.
where they use a product like dow blue board...I use
a similar product with high R-value (R-7 per inch as opposed to
similar product with R-3 per inch). this product has the R-7
I'm looking for, but also a foil facing on one side.
with this product you not only get the air seal & additional insulation
value, but when you face the foil into the attic space...it reflects
radiant heat out of the wall.

using the foam sheathing on the attic side of walls will also air seal.
as you sheetrock the interior..and make that side air tight this will
allow insulation in the stud bays to perform to rated R-value.
that in the summertime it reflects heat out...will make
the cooling of these rooms located in 130 degree attics possible.

not only should the foam sheathing cover from top to bottom plate
continously, but the seams & any penetrations should be sealed..tape
or caulk. top and bottom plates should be caulked to foam sheathing.
I use a roofing nail..or button cap nail with a large head for holding
the foam sheathing in place. nail to 2x faces of insulated stud bays,
I'd use a batt so that the insulation is easily kept in place as you work.

then..and this is the difficult part..from the bottom (sole) plate of the wall, to the
ceiling of the floor below (the attic floor) should also be sealed.
you do this by cutting foam sheathing to fit between floor/ceiling joists.
move insulation back..fit the foam sheathing..nail it to sole plate
and caulk it at the sides to the floor joists. you also caulk it to the floor
of the attic/ceiling of rooms below.
this is shown as #17 on page 5 also.

until you do this air sealing...these rooms will be difficult to condition.
a/c companies will oversize system..or supply ducts to overcome the
heat/air gain.

the way to get sheetrock sealed when work is done is to tell the crew
that you are not installing moldings. this way they will tape & float all
wall/ceiling joints. do a search for air tight drwyall approach, this
is what we want for these rooms.

understand that insulation only works when air isn't filtering through it.
cellulose doesn't air seal as well as the companies say it does.
and if there are any unsealed gaps between the cellulose & the interior
conditioned space...that the fine 'dust' filters into the house.
folks complain of excessive dust...and I know they have cellulose!
this 'dust' is actually particles of borate treated newspaper..not
something you want to circulate throughout your home.
once air movement is stopped then batts will work as well as any
conventional insulation.

short of foam insulating the roofline..the foam sheathing is the way to go.
if you are at all handy..you can diy it. hiring it out doesn't work as well as
homeowner diy. you'll take the time to do it right.
I've done this in several homes myself, overseen homeowner's install
and gone back to test & verify installs hired out.
the ones that work are either my installs, or the ones I diy'ed to homeowner through.
no one cares as much as the people who will live in the house.

also...here is some home work. southface has really great air sealing pdf's
here is a link to these pdf's for you to read through. that they include such good
pics is what makes able for us to diy. hope the link works!
http://www.southface.org/search/?cx=005817969137941356726%3Aqrrwf8e0uu4&c of=FORID%3A11%3BNB%3A1&ie=UTF-8&q=air+sealing+pdf&sa.x=13&sa.y=20

air sealing & duct sealing is your best investment. all this work should
be done prior to any added insulation. use the info on the site to get an idea of
where your house leaks.
if you can't quite get it, then a blower door & duct leakage test would be
necessary to show you where the leaks are..and this testing will also measure
the leakage. doing this testing prior to any work...and again before insulation
install in the attic is what people like me do.
for an energy rater in your area check with resnet (www.resnet.us).

oh and the bane of my existance..recessed lights. if you decide to add these holes in
the ceilings...then invest in an air tight insulation contact recessed light (ICAT)
make sure that it is ICAT by taking the light out of the package. there should be
NO openings in the outside of the recessed light. otherwise IC lights will be installed
and will be a permenant hole to the hot attic, that allows temps & insulation particles
into your home. retrofitting with air tight inserts is a costly job, better to do it right
to start with.

best of luck.


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RE: Attic insulation/remodel question

Energy Rater, thank you so very much for your input. I already had the energy audit performed (blower door test with infrared pics). So I know where the air leaks are. The auditor/contractor proposed me the scope of work based on the test results. I am not sure if you read the scope of my attic insulation. Here it is once again for your review. Please let me know if you still believe air sealing that you referred to in southface.org can't be achieved with the procedure the auditor suggested.

"Access attic trough knee walls: staple netting to hold the insulation in place
Walls: Insulation with blow-in cellulose eves to the full capacity and walls.
Floor : remove necessary boards and blow-in insulation.
Ceiling space: Blow in 12 to 14 inches of new Cellulose insulation over existing insulation. Total fill level of 15 inches. Total estimated R-Value of R49, R55 before settling.
Insulation and weather stripping knee walls with Easy Touch Cotton Insulation.
Confirm that attic has adequate ventilation.
Air sealing Attic with closed cell foam all bypasses from the house to the attic (light fixtures, can lights, exhaust fans etc.)"

Moreover, he mentioned that he is going to
1) install dry and dense blown in cellulose; since the attic, living space and basement is going to be airsealed, there will be no dust problem. He will use weather blanket cellulose insulation, if that makes any difference
2) take before and after insulation pics to prove there are no gaps in insulation.

It is really hard to find a reliable contractor who knows their stuff and do a meticulous job. Some don't even know what I am asking and some don't show up for the appointments. This is the only guy who is responsive and knowledgeable. He also has great reviews with no customer complaints. Moreover, I am not very handy. Can I take the southface.org checklist and show him that I need the attic air sealed that way? How much do these jobs typically run if installed by a contractor? Is the quotation I got from him reasonable? Please advise...


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RE: Attic insulation/remodel question

Newbie007, you're welcome. You're right, the more learned about this stuff, the more confusing...everyone has an opinion of what's best, and promises the world based off of manufacturer ratings rather than real-life application.

I'm glad to have read what energy rater la (the cajun cooler? Lol) posted...like what I gleaned from my research, his/her info seems logically based and not unneeded rocket engineering...just a lot of work and attention to detail.

Energy rater, thanks for sharing both your knowledge and links. I'm saving this post for later reference!

Newbie007, one last thing, if you have a hollow core attic door, it's probably best to replace it with a solid door...like paneling versus sheetrock.

Just a quick side note, I've also researched a bit on sound reduction/proofing, both thermal and sound regulation are complementary. In addition to heat/cold, air leaks also allow noise penetration; and the greater mass, the more thermal and sound resistant. So after all of your work, you'll also have a much quieter home. :)


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RE: Attic insulation/remodel question

it really isn't a good idea to seal around electrical
with foam. unless it is fire rated foam..and even then
there are things you should know about sealing
with cans of foam.
first is that there is very little control over where
the foam goes. in the crack...over the crack...around
the crack...who knows..there is simply too much
product to see.
second is that foam shrinks. fill holes in a hot
attic with foam this year...and go back in 3 years
& you'll see where it has shrunk. esp closed cell foam.
I learned this back in my weatherization days...
inspecting work done prior to my day.
it hasn't gotten better.

foam around recessed cans..think about what you
are doing. not only putting non code foam, around
an electrical source..but for the life of the recessed can
you have to only use led or cfl. and make sure when/if
you move that this is disclosed.

same for bath fans.

I deal with these same areas, either use the UL approved
insert to make IC can ICAT, and then seal the cut around
the can in the sheetrock (that trim covers) with mastic tape,
cover the whole thing with either UL rated covering from
inside the attic, or use ice chest method of cutting &
caulking ice chest to attid floor...keeping 4" clearance
around all sides & top.
done all these things.
but not foam. ever.

people use foam because it is easy. and it covers
any holes, note covers...not seals.
closed cell used around windows & doors in construction
voids warranties because it wracks the frames...think
about putting something that actually increases to the
point of wracking wood & metal. its crazy.

and what you pay for this temporary seal...IMO
its not worth it. if you want a long lasting seal..
there are better materials to use.

I'll attach a pic of a supply box that I took of a
mastic tape sealed supply box.
this same method is used to seal around bath
fans, supply boxes to floor, wall ceiling whichever
applies to your situation, and the gaps between
recessed can lights in sheetrock ceiling.
know that whenever there is a supply grill, bath
fan cover, recessed light trim...there is a hole
behind it.

bibs for kneewalls still won't stop air movement or
reflect heat out of walls.
and blow cellulose...and you'll have dust.
without continuing the air barrier at areas mentioned
above...and things like caulking ceiling moldings
to ceilings at top of molding & to the wall at the bottom
of the moldings..that fine dust will have entry.

I know his work sounds good...but I've seen & tested
these types of installs too many times to not know
better. this is how I came up with my recommendations.
do the install...and test it.

for his price...could you get a foam company to come in
and foam seal the walls..over any existing insulation?
this would work...and they could take plastic bags &
put batts inside of them, suff them inthe joist bays under
the knee walls & foam seal them in place.
this is the other alternative to air sealing...plus added
ins value.

I have no idea what price you were quoted.
but get more bids..call foam company..quotes are free.

the sealing of supply boxes, bath fans I can walk you
through.

oh and the only mastic tape worth purchasing is
Hardcast brand mastic #1402 tape. thick strong mastic.
others are not strong enough & mastic is not as thick.

if you do use this company..insist that the only
foam used is fire rated. as you've just doubled
his foam can costs...but you will be on the safe side.
google what happens to foam when it reaches certain
high temps. you'll understand why I avoid it around
any electrical.

you can print out the southface info, but if his mindset
is to sell you cellulose & 'air sealing' you won't be able to
change that.

anyway...best of luck...and here is the pic.


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RE: Attic insulation/remodel question

Hi Energy Rater, thank you so much for your suggestions. I wish the insulation contractors I met were at least half as knowledgeable and practical as you. hats off to you throwing away such great suggestions for free. Kudos to your passion for the profession and to help others preventing from making mistakes.
Now, I have gone through your posts at least 20 times to understand your recommendations and I think I got it.
A few questions:
1. I couldn't quite understand if you talked only about air sealing and not insulation? or by following your method of air sealing, I can achieve insulation too?
2. Foam sheathing: I use this for attic exterior side walls, gable walls, side knee walls, side attic floor (crawl space) and use batts in plastic bags and place between the rafters under sloping roof - correct?
4. Should I put any other conventional form of insulation on top of foam sheathing? If so, what type?
5. what is the product that you use that has R-7? Does it also have foil on one side? while doing a search on foam sheathing, I came across "1.5"X4'X8' R7.5 Foamular 150 rigid foam insulation" at Menards. Can i use this?
6. How should I air seal and insulate the roof directly above my attic center ceiling?Foam sheathing?
7. I currently have loose fiber glass insulation under the sloping roof. Should I remove and replace with batts in plastic bags?

I also obtained a couple of foam quotes. Since it required me to tear up the paneling to studs, I didn't go that route. But per your recommendation, I think I should replace it with drywall anyway because of air leaks thru paneling. The foam quote was for $2108 for open cell and $5K closed cell spray foam. This guy uses Icynene. The scope of work includes a) attic roof line - 5" open cell 1/2 lb. spray foam OR 4" closed cell 2 lb spray foam b) exterior gable walls - 3" open cell 1/2 lb. spray foam OR 3" closed cell 2 lb. spray foam. Option - apply ignition barrier over exposed foam if required - $1.25 per s.f.

If I go this route, don't I have to do any air sealing? I also read that open cell foam absorbs water from the roof and will have leaks in the interior attic walls. Also foam vs cellulose seems to be a very delicate topic. There are obvious supporters and critics for both.


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RE: Attic insulation/remodel question

Hi Energy Rater, thank you so much for your suggestions. I wish the insulation contractors I met were at
least half as knowledgeable and practical as you. hats off to you throwing away such great suggestions for free.
Kudos to your passion for the profession and to help others preventing from making mistakes.
Now, I have gone through your posts at least 20 times to understand your recommendations and I think I got it.

LOL!

A few questions:
1. I couldn't quite understand if you talked only about air sealing and not insulation?
or by following your method of air sealing, I can achieve insulation too?

what currently is in the walls of this dormer room (kneewalls) my assumption was that there was
already some type in place...yes ... no??
if no, then use a batt insulation. easy to attach firmly in stud bays.
then foam sheathing goes over the insulated wall..attached with button cap nails, caulked top & bottom
seams taped.

2. Foam sheathing: I use this for attic exterior side walls, gable walls, side knee walls, side attic floor (crawl space) and use batts in plastic bags and place between the rafters under sloping roof - correct?

all walls (foil facing out into attic, if you chose this type), between floor joists. caulked to air seal.
would have to see a pic to see exact configuration. not sure what access you have at rafters..or what type & R-value
of insulation. pic would help & confirmation of size (2x6?) roof rafters.
batts in bags between floor joists IF spray foam is used..
without spray foam you have to cut, fit and caulk foam board between floor joists.

4. Should I put any other conventional form of insulation on top of foam sheathing? If so, what type?

no insulation goes inside joist/wall bays...foam sheathing on top.esp with foil..foil needs to face attic space to
reflect heat.
5. what is the product that you use that has R-7? Does it also have foil on one side? while doing a search on foam sheathing, I came across "1.5"X4'X8' R7.5 Foamular 150 rigid foam insulation" at Menards. Can i use this?

I use this: http://building.dow.com/na/en/products/insulation/tuffr.htm
correction R-6.5 not R-7... the lesser R-value is difficult to work with as it has less rigidity, and is a pita to work with.
if you opt to not do the foil faced, then dow blue board or corning pink board will suffice. the plastic
film is hard to cut after razor dulls. (and how do I know this?? sweating & fussing in an attic..LOL!)

6. How should I air seal and insulate the roof directly above my attic center ceiling?Foam sheathing?

depends upon access, depth of rafters & venting of this dormer. pic??

7. I currently have loose fiber glass insulation under the sloping roof. Should I remove and replace with batts in plastic bags?

see above. if you buy batts for the walls...just buy an extra roll.

I also obtained a couple of foam quotes. Since it required me to tear up the paneling to studs, I didn't go that route.

no no...they spray from in attic to paneling. don't tear out walls. what type of access do you have to this space?
I've often cut access for foam insulators that was put back in place once work was done.

But per your recommendation, I think I should replace it with drywall anyway because of air leaks thru paneling. The foam quote was for $2108 for open cell and $5K closed cell spray foam. This guy uses Icynene. The scope of work includes a) attic roof line - 5" open cell 1/2 lb. spray foam OR 4" closed cell 2 lb spray foam b) exterior gable walls - 3" open cell 1/2 lb. spray foam OR 3" closed cell 2 lb. spray foam. Option - apply ignition barrier over exposed foam if required - $1.25 per s.f.

I'd drywall over paneling. why remove it..paneling is really thin.

ok lets talk about code requirements. in my area R-30 is code for attics, R-25 for

cathedralized ceilings. in essence your attic becomes a cathedralized ceiling once it is insulated.

so..here we over fill 2x6 rafter bays 6-7" of open cell. sheetrock to interior of the rooms is ignition barrier.

I've had many conversations with local code to be sure that this meets their requirements. I'd suggest you do the
same..not the foam companies.. code enforcement.

closed cell has a higher R-value, so less is required. but keep in mind R-values per inch of both closed
& open cell. open is about R-4, closed cell is about 6-6.5. depth of foam HAS to meet code R-value.

If I go this route, don't I have to do any air sealing?

if done correctly..the foam eliminates the need for air sealing.
this is the tradeoff..materials & labor vs foam insulation. see why it is popular?

I also read that open cell foam absorbs water from the roof and will have leaks in the interior attic walls.

Also foam vs cellulose seems to be a very delicate topic. There are obvious supporters and critics for both.
IMO roofs will leak..it isn't an if, its a when. I prefer a foam that lets the water exit rather than one
that traps it against the roof decking. but for cold climates..closed cell seems to be the choice.

there will always be debates about insulation types..fg, cellulose, rockwool, foam...

its like trane vs carrier when american standard & bryant are the same equipment.

foam, like any insulation...when done correctly is a good product. each has benefits &short commings.

But if you chose to foam..ask for pics of installs & call the supplied refrences to make sure
that what was promised was actually achieved. like anything...you have to decide who is
the better installer & if it is the right product for you.

best of luck.


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RE: Attic insulation/remodel question

Hi Energy Rater..thanks for more useful information as always..I have posted the attic pictures in the below link. Hope you will be able to access.

https://plus.google.com/photos/107461476070647929504/albums/5893080782358797041?authkey=CLu34uK52Yp4

As you can see, other than the limited insulation under the sloping roof, I don't have any insulation on the floor, gable walls and the knee walls. Also there are many gaps for air to leak. At this point I don't know what type of insulation I have by the walls next to windows and above the ceiling. I am assuming none. So at this point, I believe its better to start from scratch, remove the existing insulation and redo. Also tear open the paneling by the window wall as well as the ceiling drywall and do the insulation and air sealing as I don't dont any other access to them at this point. Do you agree? Hopefully after checking the pictures, you will be able to make some more suggestions.


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RE: Attic insulation/remodel question

I get an error message & no pics.
try again?


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RE: Attic insulation/remodel question

please try now. My bad, I should have used the link feature.

Here is a link that might be useful: Attic pics


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RE: Attic insulation/remodel question

hmmm...let me think about this for a little while.

so,,,,when should I show up to work? LOL!

be back later.


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RE: Attic insulation/remodel question

the problem [in retrofitting insulation into old homes] is that added insulation inevitably caused moisture/mold issues

Only when vapour barriers--which are different from air barriers--are added inappropriately and when solid masonry walls are inappropriately insulated. (See here.)

OPs home is in a cold climate and some strategies differ from those deep in the bayou. Air sealing works everywhere.


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RE: Attic insulation/remodel question

ok...so unless I misunderstand...you aren't doing anything
with the masonary wall. correct?

as we are working with kneewalls of dormer..not
the masonary wall shown in pics?

so...lets do this picture by picture...
pic 1 the masonary wall is the window wall..
the paneling is actually individual boards?
the thing about sheet paneling is it only leaks
air from sides top & bottom. individual boards
leak at each joint on both sides & ends.
or is this a deep groove paneling & not
seperate boards?

pic2 attic access door..another leaky area,
but nothing weatherstripping wont solve..
and on this door..you'd attach foam sheathing
to attic side.

pic3 hmmm.attic is floored...
if you spray foam seal the walls of the
dormer room...would you be willing to still pull
up boards to allow access to foam seal
between the floors? those big gaps in the
floor in the attic continue into the floor of the
dormer room..just hidden under the pretty flooring.

pic4 batts in rafter bays..what kind of shape is your
roof in? chimneys properly flashed? I'd want the roof
& flashing to be inspected prior to adding any
insulation in joist bays. like I said previously...this
isn't something we do here.
I wonder what the R-value of those batts are.
doesn't look like much..R-13? 3.5" thick?
at the bottom of a 7.5" rafter bay...air above...
air below.
not much performance there!
and there is Worthy's masonary wall again!

pic5 remember that picture I posted with the
supply grill & mastic tape...this is where you
use it. hardcast brand #1402..sticks to
wood & metal. lasts a long long long time.
and tape those exposed seams on the
ductwork...just because you have the right
product to do it.

pic 6 open wall? can you put your hand into those
openings? how deep are they?
plumbing penetrations can be sealed with caulk...
or caulk & backer rod if the gaps are bigger than
1/4". (and yeah...we know they are!)

depending upon where those openings go..
and how deep they are will determine what to
do at this area. if they dead end into the wall..fine.
but if they continue..you gotta seal them off.
then insulate.

pic7 worthy wall again. batts at bottom of rafters..but..
the dormer kneewall. describe it a bit.
it looks like it has boards from the top of the wall
about halfway down the wall, yes? (see I can write
like a cajun..even if I'm a transplant)
are there empty wall cavities behind the boards
from the top? knock on them...
from the floor up...is that a stud wall with area to
insulate?
reason I"m asking..is you don't want to just put foam
board over empty wall behind boards from the top.
insulation surrounded by air..doesn't do much.

pic8 Oh..so one of the walls are sheetrock.
must be the wall with the attic access..
studs are 2x4 on flat..leaving us 1.5" to insulate.

so... describe the wall configuration of pic 7.
verify for me if you can if the boards at the
top of the wall cover an empty wall stud
bay..and that bottom is 2x4 on edge??
trying to get a handle on room to insulate
within stud bays.

your questions & comments with my inserts...
As you can see, other than the limited insulation under the sloping roof, I don't have any insulation on the floor, gable walls and the knee walls. Also there are many gaps for air to leak. At this point I don't know what type of insulation I have by the walls next to windows and above the ceiling. I am assuming none.

I'd think that they made the insulation in the rafter bays
to reach the peak of the roof. look at pic 7.
to me it looks like the batts continue beyond the top
of the wall. you can see better than I can, so push
the insulation upwards & see what you can see.
easy now..don't want to tear that dry brittle paper.

So at this point, I believe its better to start from scratch, remove the existing insulation and redo.

Also tear open the paneling by the window wall as well as the ceiling drywall and do the insulation and air sealing as I don't dont any other access to them at this point. Do you agree? Hopefully after checking the pictures, you will be able to make some more suggestions.

dunno...still weighint pros & cons of this. let me sleep
on it & I'll get back to you.

did they thermal scan the wall with the window?
something for you to think about...
is that sometimes if there isn't a problem..you
just air seal and move on. any signs of problems
at masonary wall that you can see from inside
the room? those old folks knew stuff..it might
be best to leave it alone. there is a lot you
can do towards air sealing from inside the room.
think clear caulk.

I'm beat...talk to you tomorrow.
and tomorrow I'll re-read thread in its entirity.
there are some questions about your first floor
I want to ask...after we decide on attic/dormer
options. don't let me forget!

best of luck.


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RE: Attic insulation/remodel question

Energy, I have added additional infrared pics of the attic. please check the link.

1) pic 1 I am not sure if the paneling is individual boards or deep groove paneling. hopefully the additional pics can help you determine that. looks like there are air leaks between each panel, that makes me believe its individual boards...not sure..sorry..forgive my ignorance
2) pic2 : OK, will attach foam sheathing to the attic access door..
3) Pic 3. Yes, I am willing to still pull up boards in the knee wall space to allow access to foam seal between the floors. However, I am not willing to remove the pretty hardwood flooring to air seal the gaps underneath. what are my options
4) Pic 4: I haven't gotten any inspection of my roof, but I believe it is in good condition. I don't have stainless steel chimney lining or for that matter any kind of lining. I have to get this done. batts in rafter bays. I think the auditor said the R-value of those batts are either R9 or R11..can't remember..but its very poor.
5) Pic 5: Hardcast tape..stellar recommendation. I think a caveman could do it reading your instructions. will do for sure
6) Pic 6: The plumbing work is from the bathroom in the attic. It is a 5 ft dormer. The pipes from the attic bathroom go through the first floor into the basement. So there is a bathroom in the first floor right below the attic bathroom. first level bath doesn't have a vent fan but the attic bath does.
7) Pic 7: The boards you see are probably from built in storage chest and reading desk/TV chest. Otherwise, the space between the stud bays in the knee wall look exactly like in pic 5. The storage chests are on the east side of the attic. My attic has 2 bed rooms and 1 bath in between the 2 bed rooms. the 2 bed rooms are identical in shape and size; on either side of the bathroom
8) The drywall is from the wall attached to bathroom. When I had the bathroom remodeled last year, my contractor put drywall.

Pic 14: I watched several YouTube videos the other day and came across "Silverglo foam board insulation" recommended by Dr.Energy Saver. Will this work for me? whats your take on this?

Here is a link that might be useful: Attic pics


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RE: Attic insulation/remodel question

Found this additional information on my roof and chimney from the home inspection report. I also added the roof and chimney pictures

PRIMARY ROOF SURFACE
AGE: undetermined
SURFACE MATERIAL: conventional asphalt/ fiberglass shingles
PITCH OR ROOF ANGLE: > 6" of rise for each 12" of run
NUMBER OF SHINGLE LAYERS PRESENTLY ON ROOF: 1 layer
WHEN NEW, THIS TYPE OF ROOF CAN BE EXPECTED TO LAST: 15 to 20 years
CONDITION OF ROOF SURFACE: good. There are no signs of active roof leaks.

BATHROOM /DORMER ROOF SURFACE
AGE: undetermined
SHAPE: shed roof
SURFACE MATERIAL: rolled asphalt
PITCH OR ROOF ANGLE: less than 1" of rise for each 12" of run [considered flat]
NUMBER OF SHINGLE LAYERS PRESENTLY ON ROOF: 1 layer
WHEN NEW, THIS TYPE OF ROOF CAN BE EXPECTED TO LAST: 10 years
CONDITION OF PORCH ROOF SURFACE: good. There are no signs of active roof leaks.

ROOF PENETRATIONS
ELEMENTS PENETRATING THE ROOF SURFACE ARE: 2 plumbing vents, 4 attic vents, a masonry chimney

CHIMNEY, ABOVE THE ROOF
AGE: original
MATERIAL: brick
NUMBER AND TYPE OF FLUES: single flue with a clay tile liner
CHIMNEY PROTECTION: a concrete chimney crown
CHIMNEY CONDITION [EXTERIOR] ABOVE THE ROOF: functional, except for the condition recommended for correction below
INSPECTOR'S NOTE:
• There are areas where the mortar between the bricks on the chimney has deteriorated and in some cases is missing. The prompt repair of this condition ["tuck pointing"] is recommended before additional damage can occur.
• The mortar has deteriorated on the top of the chimney.
• A flue cap and vermin screen can be added to this chimney for extra protection

CHIMNEY FLASHING
This material forms a weather tight transition between the masonry chimney and the roof surface.
AGE: undetermined
FLASHING MATERIAL: galvanized steel
CONDITION OF CHIMNEY FLASHING: functional, There are no signs of failure or active leaks in the chimney flashing. The galvanized steel flashing at the chimney has rusted. Regular painting with good quality rust inhibiting paint is recommended and can extend the life of this flashing indefinitely. There are no signs of failure or active leaks in the chimney flashing.


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RE: Attic insulation/remodel question

thanks for additional info.
I thought it was one room in attic...not
2 bedrooms & bath.

I'm heading out the door for work...
but haven't forgotten.

oh and thanks for IR pics.

good that they did them in the heat of the
summer.

ttyl,
Debbie


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RE: Attic insulation/remodel question

the blown insulation will go under flooring & not back in rafters??
and thanks for the IR pics.
were they blower door testing when IR pics were taken?
(house depressurized) or just scanning?
good that you did the testing in cooling season. works better for me, due to hot climate experience.

1) pic 1 I am not sure if the paneling is individual boards or deep groove paneling. hopefully the additional pics can help you determine that. looks like there are air leaks between each panel, that makes me believe its individual boards...not sure..sorry..forgive my ignorance

I think they ar individual boards. pic 10 shows the heat
comming thru cracks. and it isn't ignorance...just different
things we specialize in!

2) pic2 : OK, will attach foam sheathing to the attic access door..
construction adhesive to hold foam board to door & button cap nails. I like Loctite Power Grab.

3) Pic 3. Yes, I am willing to still pull up boards in the knee wall space to allow access to foam seal between the floors. However, I am not willing to remove the pretty hardwood flooring to air seal the gaps underneath. what are my options.

I'd never suggest you disturb the pretty hardwood floors!
what I propose is to cut access to install the foam seal between floors. as I explained before there are two options.
one would be to bag insulation (maybe some of the rafter insulation) and stuff the bag tightly between floor joists.
then foam would be sprayed to seal the bag in place. you'd want to make sure that the foam seals well..top, sides & bottom. once it is foamed, you won't see the bag..its just an insulated space filler.

second option would be to remove more boards & use the
foam sheathing. more labor intensive...cut foam board to fit tightly..nail securely & caulk to air seal. investment in time labor & materials.
and btw...they do sell foam diy kits like Tiger Foam. my SO used this to do some work at his son's home in Indianna.
little learning curve, but not too bad if you watch videos &
wear tyvek suit..goggles & gloves. foam is a pita to get off your skin. and off clothes..time to throw them out.

this way you are stopping the air flow in the sub-floor under the new flooring.
4) Pic 4: I haven't gotten any inspection of my roof, but I believe it is in good condition. I don't have stainless steel chimney lining or for that matter any kind of lining. I have to get this done. batts in rafter bays. I think the auditor said the R-value of those batts are either R9 or R11..can't remember..but its very poor.

I'd have an experienced roofer with good refrences take a look at flashings & the 2 plumbing vents, 4 attic vents, masonry chimney prior to insulating..
I'd put the batts at R-11-13. not much is it!

5) Pic 5: Hardcast tape..stellar recommendation. I think a caveman could do it reading your instructions. will do for sure

good! it is hard to describe, but a pic is worth a lot of words.
let me know if you have problems getting the HC1402.

6) Pic 6: The plumbing work is from the bathroom in the attic. It is a 5 ft dormer. The pipes from the attic bathroom go through the first floor into the basement. So there is a bathroom in the first floor right below the attic bathroom. first level bath doesn't have a vent fan but the attic bath does.

does bath fan for attic bath vent out of the attic?
you'd have to seal around the plumbing pipes. caulk & backer rods.

7) Pic 7: The boards you see are probably from built in storage chest and reading desk/TV chest. Otherwise, the space between the stud bays in the knee wall look exactly like in pic 5. The storage chests are on the east side of the attic. My attic has 2 bed rooms and 1 bath in between the 2 bed rooms. the 2 bed rooms are identical in shape and size; on either side of the bathroom

and I was thinking your upstairs was just the bedroom
this description & the pic of your house helps me to visualize. so same window in second bedroom ?

so lets talk about the IR pics.
all the leakage sites show well.
even though you'll use batts in the walls & foam sheathing
to attic side of walls, you'll want to back up that air barrier
from inside the room. best to have primary & secondary
barriers.
at ceilings (see pic 10)
caulk top paneling to sheetrock ceiling.
can't tell if there is molding..if so caulk top
of molding to celing, bottom of molding to wall.
caulk corners & any gaps. Use the Alex brand
Dap crystal clear 25+ year life. goes on white..so
you can see where you are & dries clear in about 24
hours.
you'll have to make the call about caulking each gap
in each board. this could be done from attic side
if caulking skills need honing. installing the foam
board will stop a lot of this..but secondary air barrier
& all that.
from the attic side you'll need to caulk the sole plate
to subfloor to seal gaps between subfloor boards & to seal
subfloor to floor. it will be time consuming, but the
foam board doesn't always seal this as well as
other areas.

caulk window frames to walls. while you are at the
windows look for gaps where trim pieces come together.
if you have an unbroken paint seal..youre good. if not
you'll need to caulk trim.
btw...spiderwebs are an indication of air leaks. so
anywhere you see spiderwebs...look for the crack/gap.
and caulk it.
where the sloped wall meets the kneewall...caulk.
tip:
I caulk with a damp cloth in my hand. run the bead of
caulk, use the pad of your finger to push the caulk into
the gap, wipe of the excess with the damp cloth.
rinse the cloth often or you'll have shinny streaks where
you use the cloth.

make sure that the gap is well filled. if the gap is large
use a backer rod, or make another pass with the caulk
once first install has dried. this applies to all areas
to be caulked.

you'll also need to caulk the bookcase. similar
to the other areas you've caulked.

link to show you what backer rod looks like..you find it
in the weatherstripping section.
http://www.dap.com/product_details.aspx?product_id=356

8) The drywall is from the wall attached to bathroom. When I had the bathroom remodeled last year, my contractor put drywall.

got it.

Pic 14: I watched several YouTube videos the other day and came across "Silverglo foam board insulation" recommended by Dr.Energy Saver. Will this work for me? whats your take on this?

I see that 4" foam sheathing! bet that costs about $15 per inch. It looks like the lower R-value foam to me. see how the end looks like bean bag foam pieces molded together.
that's my guess.If I'm right then the R-value of this product is about R-3 per inch. compared to R-7 per inch of polysi
product. I'd check on costs.

what do you think of what they are doing in the pic?
I've done similar installs (different foam board)
to make upstairs attic small storage areas unvented,
similar to pic in southface pdf.

for the kneewalls. sloped ceiling areas I'd use R-13 or
high density R-15 if cost isn't out of the box. sometimes
it just isn't worth the upcharge for a big ol R-2.
batts are easy to install.. sharp razor knife, straight edge to
cut batts, staple gun.

do your caulking first, then install batts, stapling flaps of
paper backing of batts to faces of 2x's.
then the foam sheathing over the batts, caulked, taped
& nailed.

I don't know if it is just the way the camera caught the wood of the walls from the attic..but that is some pretty wood. shame to cover it up!

remember what I posted previously about the recessed lights. don't just foam them. instead either use ICAT inserts
or cover them from inside attic & seal in place. see other post. then drop the trim from inside and use hardcast to
seal between housing & cut in ceiling. do same at bath fan
openings...drop cover hardcast cut.

things to know about hardcast 1402 is that it sticks to many
surfaces..and comes in a 3" width. lots of times I cut it
lenghtwise into 1 1/2 wide strips, saves tape when gaps
you are covering are not large.
if it starts sticking to your fingers after working with
if for a while, dampen your fingers...and it won't stick
as badly. otherwise sometimes it feels as if it will
pull your finger prints off.

another hard learned lesson is the basis for this
tip:
also take a pencil before you remove bath fan cover, recessed light trim, supply air/return grill. trace lightly
on the ceiling/wall area around grill/trim/cover.
keep the tape within the area covered.
if you put the tape & try to move it..it ain't happening! you can pull the paper off sheetrock with mastic tape.

thats all for now. let me know what I need to
explain better. this is a LONG post!

best of luck.


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RE: Attic insulation/remodel question

Thanks energy!!! you da best!

Here is the summary I have based on all your recommendations. Please review and let me know if I got this right.
Step 1: Get the roof, plumbing and attic vent protrusions inspected
Step 2: Look for air leaks throughout the attic and airseal by covering with foam where applicable and caulking. Follow all your tips and tricks for airsealing..
Step 3: I don't know if I have soffit vents..if so install baffles for soffit vents and don't cover them with insulation.
Step 4: knee wall floor space: remove the floor boards, lay batts over existing insulation (yes i have some blown in fiberglass under the floor boards) and put foam board on top - caulked, taped & nailed
Step 5: under sloping roof: use R-13 or R-15 batts, staple the paper flap to the stud bays and then put foam board on top - caulked, taped & nailed
Step 6: masonry wall, window wall, above the drywall ceiling, behind the knee wall : Lay batts and put foam board on top - caulked, taped & nailed - can I nail the foam board to the masonry wall?
Step 7: behind knee wall access door: foam sheating using Loctite foam adhesive

Tools I need:

1. Foam board: TUFF-R insulation board with R value of 6.5
2. Batts (faced or unfaced?)
3. Loctite Power Grab construction adhesive to hold foam board to door & button cap nails
4. Caulk: Alex brand Dap crystal clear 25+ year life for general purpose and fire rated caulk around electric
5. Hardcast 1402 mastik tape to cover supply and return registers, recessed trim, bath fan
6. Tiger foam
7. backer rod around plumbing
8. staple gun
9. goggles, tyvek suit
10. razor knife, etc

Now some more questions:
1. As you observed, the paneling is some pretty wood. hickory actually. I got lot of compliments for it. If I don't wanna hide that paneling by putting drywall over the top, can I just air seal by caulking all the gaps between individual board joints? I will then paint my paneling. what about ignition barrier?

2. window wall - can I airseal and caulk the areas where paneling meets ceiling, floor and side knee wall with no insulation? that way I don't have to remove paneling?

3. By placing batts and foam board on top, what is the R value I will be getting? Batt is R13 and foam board is 6.5. does it mean its around R20? Is this sufficient for Chicago code?

4. Batts - what brand/make/specifications? like faced or unfaced?

5. There are 4 attic vents that penetrate the roof. Any plans around insulating that area? I shouldn't cover them with insulation correct?

I look forward to hearing from you and finalize the insulation plan.

Thanks,
Krishna


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RE: Attic insulation/remodel question

Step 4: knee wall floor space: remove the floor boards, lay batts over existing insulation (yes i have some blown in fiberglass under the floor boards) and put foam board on top - caulked, taped & nailed

floors...it will be difficult to add to insulation value under second story floors. put the foam sheating BETWEEN the joist bays at the perimeter of the upstairs rooms & air seal.
the foam sheathing should continue from the install of
the same on kneewalls to attic floor/1st floor ceiling.
take another look at southface pdf page 7..5..not
sure which page. what I want you to see is the
kneewall sealing.they show both the install of the
foam sheating on the walls...and cutting it to
fit inbetween ceiling/floor joists.then caulking it to air seal.

when you are faced with an install that you can't
really improve...like adding insulation between floors
on floor of attic, air sealing it so that air doesn't move
over & through it is the tradeoff.
foam company could blow insulation...but it would
require that they come & blow this area...leave...
you get the foam sheating installed..then the
insulation company come back for whatever else
you decide upon for the rest of the attic insulation.

as these rooms are above a conditioned space..
I'd spend my time with the air sealing of the
perimeter of the rooms as opposed to adding insulation
& then air sealing.

it is when the insulation has air movement through it
that it doesn't perform. keeping the air at rest is the
goal @ this area...not necessairly adding more insulation.

Step 6: masonry wall, window wall, above the drywall ceiling, behind the knee wall : Lay batts and put foam board on top - caulked, taped & nailed - can I nail the foam board to the masonry wall?

no, you can't nail into masonary wall.
are you talking about inside the room or the exposed
wall from in the attic? more on this later in this post.

Step 7: behind knee wall access door: foam sheating using Loctite foam adhesive.

you can use some button cap nails to add more holding.
just make sure they are shorter than depth of foam & wood of door.

Now some more questions:
1. As you observed, the paneling is some pretty wood. hickory actually. I got lot of compliments for it. If I don't wanna hide that paneling by putting drywall over the top, can I just air seal by caulking all the gaps between individual board joints? I will then paint my paneling. what about ignition barrier?

I'd air seal it rather than cover it up. lots of ways to brighten up the area without covering or painting such pretty wood.
rather than attempt it from inside the room...it looked like from the pics that you have access to the walls from in the attic. I'd do my caulking of the wall boards from there.
from inside the room you'll do the corners, to the moldings..
moldings to walls & floor molding to wall. the sealing of the sole plate is another thing fo caulk from attic side.

2. window wall - can I airseal and caulk the areas where paneling meets ceiling, floor and side knee wall with no insulation? that way I don't have to remove paneling?

that is exactly what I'd do. as long as the upstairs has been built, there have been no issues that you know of or can see with the masonary wall that is covered by panels.
so rather than open it up & improve on something that has served well...just let it alone & air seal.

3. By placing batts and foam board on top, what is the R value I will be getting? Batt is R13 and foam board is 6.5. does it mean its around R20? Is this sufficient for Chicago code?

keep in mind that this R-value is for walls.
do you still plan to blow cellulose on attic floors?
the attic floor R-value is what you have to achieve
your area's recommended R-value. not the walls,
you are over insulating what code requires for walls.

4. Batts - what brand/make/specifications? like faced or unfaced?

I like john mansfield faced batts. the white fg is much less
itchy than the yellow or pink batts. just remember...don't scratch the first time...or you'll be scratching all day.

5. There are 4 attic vents that penetrate the roof. Any plans around insulating that area? I shouldn't cover them with insulation correct?

passive vents I hope & not pav's?
are you going to bibs the roof decking or blow the attic
floor. Sorry...I'm not quite clear on this.

Masonary walls. if you do decide to address the masonary
walls that are in the attic...Worthy linked a good article from buildingscience.com from what I understand options would be spray foam, if open cell the face of the foam should be painted with latex paint. if foam sheathing boards, they need to be in full contact with the wall. difficult with
irregularities of the wall. you could use construction adhesive & caulk on both the wall & the foam sheathing
thick enough to seal any gaps between wall & foam board.
the only way I know of to attach to masonary is this:
tap con screws (blue masonary screws) using a masonary drill bit drill pilot holes thru foam sheathing into the masonary wall. as you'll need a larger surface holding area
for the screw than just the screw head, you could put furring strips & drill/screw through the strips, foam sheathing & into the walls. or take some of the caps off the
button cap nails & put on screws.

as we refine your list...let me know if any explanations
need more detail.

have a good weekend!


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RE: Attic insulation/remodel question

Thanks Energy for clarifying things for me. I am still a little confused about step 4: insulating the attic floor (non living space). For walls and sloping roof, foam sheathing goes on top of insulation. Is this the same case for floor or is the opposite? My understanding of your recommendation is that I put foam sheathing on top of the floor boards (there is loose fill fiberglass underneath those floor boards) and then blow cellulose on top of foam sheathing to the recommended R value for floors per Chicago code? Please advise. Thanks!!


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RE: Attic insulation/remodel question

only one thing I didn't explain well...

lets define living space you have first floor
which attic floor insulation would go over.

then you have second story living space
the rooms with kneewalls to attic.

non living space would be porches or garage.

for walls & sloped ceilings of second story
batts/ then foam sheathing on top nailed
to faces of studs.

for the rest of the attic above the first floor
no foam sheathing. just insulation.

my concern is with this is the floored area
above first story.
is insulation co going to pick up the flooring
& blow underneath it?

I remember somewhere in the beginning of the thread
you mentioned R-50 before it settles.
keeping this in mind...please
explain how insulation company proposes
to insulate this area..attic above first floor.

you aren't going to bibs & cellulose in roof rafters..
correct?
these batts installed would be removed..and
used to stuff into plastic bags between floor/ceiling
joists of second story rooms, for foam seal of this area.

the insulation company bid insulating the attic floor
right?

my concern is R-value per inch & what depth of
ceiling joists are. unless the joists are built up higher
you are limited to the R-value per inch of the joists.
I'm not sure what code is for your area, probably
what insulation company bid.

I'll be here on & off during the rest of the day.
too hot outside to do all the weed treatments at once!


 o
RE: Attic insulation/remodel question

only one thing I didn't explain well...

lets define living space you have first floor
which attic floor insulation would go over.

then you have second story living space
the rooms with kneewalls to attic.

non living space would be porches or garage.

for walls & sloped ceilings of second story
batts/ then foam sheathing on top nailed
to faces of studs.

for the rest of the attic above the first floor
no foam sheathing. just insulation.

my concern is with this is the floored area
above first story.
is insulation co going to pick up the flooring
& blow underneath it?

I remember somewhere in the beginning of the thread
you mentioned R-50 before it settles.
keeping this in mind...please
explain how insulation company proposes
to insulate this area..attic above first floor.

you aren't going to bibs & cellulose in roof rafters..
correct?
these batts installed would be removed..and
used to stuff into plastic bags between floor/ceiling
joists of second story rooms, for foam seal of this area.

the insulation company bid insulating the attic floor
right?

my concern is R-value per inch & what depth of
ceiling joists are. unless the joists are built up higher
you are limited to the R-value per inch of the joists.
I'm not sure what code is for your area, probably
what insulation company bid.

I'll be here on & off during the rest of the day.
too hot outside to do all the weed treatments at once!


 o
RE: Attic insulation/remodel question

Hi Energy, yes the insulation company did bid on insulating the floor. They will remove necessary boards and blow-in cellulose. See pic 3 - The wooden boards in the attic behind the knee wall are nailed to the floor joists. So I don't know yet how deep the joists are. I see some loose fiberglass insulation underneath these boards through some cracks/gaps on the wooden floor. Can I just foam seal the gaps between these boards and may be blow loose fill fiberglass over? There is product called Atticat at Home Depot. These boards are really confusing me with my approach to insulating this area. But here is what I think I should do - without having to remove the boards. Once the insulation is done, this is how it will look.
I will have existing loose fill fiberglass in attic floor joists then the wooden board sealed with foam and then Atticat Loose Fill Blown-In Insulation. Please let me know if this will work.


 o
RE: Attic insulation/remodel question

OK, I just went looked through the wooden boards. The depth of the attic floor joists is 8 inch. I have 3 inch loose fill insulation. joists are spaced 16 in apart.


 o
RE: Attic insulation/remodel question

pardon the shortness of the post...its been a long day...
always ain't that right? (line from a song I like fwiw)

this is what I see in your post earlier on:
Floor : remove necessary boards and blow-in insulation.
Ceiling space: Blow in 12 to 14 inches of new Cellulose insulation over existing insulation. Total fill level of 15 inches. Total estimated R-Value of R49, R55 before settling

8" joists give you 7.5" of room for insulation...how in the
heck do they think that cellulose installed in these areas
will achieve 'estimated' R-value of R-49...R-55 before settling? where is the 12-14" going to appear from???

the first thing is that you understand this post & that the insulation
co can get on board with achieving the required R-value.
as always...if things need more explanation...you know how to contact me...posting here...or emailing me.\\
my email is on my member page/profile.


cellulose is about R-4 per inch, being generous...lets say
8" @ R-4 per inch. 4x8= R-32. a far cry from R-49.
unless the floor boards (attic floor) are removed
R-32...and that is before settling.
now we have increased the depth by toenailing..toe
screwing? 2x's perpendicularly to existing joists.
if you use 2x8's ...that is R- 64 total...so 2x6's would
achieve the depth..prior to settling. once it settles...
then you'd be in te R-50 range.
rather than putting indivudual boards back down...
(think labor costs) less costly & time invested would
be plywood.

when you have wood sandwiched between insulation...
it derates the R-value. Wood has R-value of R-1 per inch. once the insulation under the floor boards settles..
you have an air gap ...which further derates the install.

this company is lacking in understanding the above.
that you are one of the rare homeowners that is understanding the install & issues of the proposed install
is probably out of the realm of their understanding.

perhaps a better option would be to bibs the roofl line
& blow cellulose there. or is it fiberglass now?
granted it would be an out of the norm install..
but without a lot of lumber costs & education of insulators
it may be the less expensive route.

have this discussion with your insulation company.

time to put my tired self to bed..gotta get up @ 5 am
to be on the job tomorrow. hopefully Wednesday...
I can start later. cross your fingers for me,
and I'll do the same for you.

best of luck. & take care.


 o
RE: Attic insulation/remodel question

you didn't send email so that I can reply by email..so this is in relply to your email.

Almost missed this Krishna!!

On Fri, 12 Jul 2013 14:35:24 -0700 newbie007 writes:
[This message originated at GardenWeb]

Hi Debbie,
I hope you are doing well and had a great July 4th.
This is Krishna from gardenweb forum. Sorry I couldn't respond to your last post about attic insulation. I was out of station for July 4th weekend and then got busy at work.
The insulation company proposed R49-R55, above the ceiling (for the top attic) not for 2nd floor joists. for floor joists, they will remove necessary wood boards and blow cellulose. I assume to an extent that it gives R49-R55. Anyway, if I am doing it myself, I will not use the insulation co. Hence I am asking these questions to understand the process completely and do it by myself, may be with the help of my handyman.
It appears like there are 2 options for the insulation approach.
1) rafter insulation (I read this is for new construction projects and closed cell spray foam is the best)
2) knee wall insulation (floor/ceiling joists, behind knee wall, behind kneewall and sloping roof intersection, in the top attic above the ceiling and then on to the other side. (I read this is the procedure for finished attic or retrofit insulation projects). (cheaper and DIY but labor intensive), Also I believe this is the option we have been talking about in our discussions.
You stated:
'floors...it will be difficult to add to insulation value under second story floors. put the foam sheating BETWEEN the joist bays at the perimeter of the upstairs rooms & air seal. the foam sheathing should continue from the install of the same on kneewalls to attic floor/1st floor ceiling. take another look at southface pdf page 7..5..not sure which page. what I want you to see is the kneewall sealing.they show both the install of the foam sheating on the walls...and cutting it to fit inbetween ceiling/floor joists.then caulking it to air seal. when you are faced with an install that you can't really improve...like adding insulation between floors on floor of attic, air sealing it so that air doesn't move over & through it is the tradeoff. foam company could blow insulation...but it would require that they come & blow this area...leave... you get the foam sheating installed.'
You also stated:
'for walls & sloped ceilings of second story batts/ then foam sheathing on top nailed to faces of studs. for the rest of the attic above the first floor no foam sheathing. just insulation.'
I am confused between these two statements. In the first statement, you are asking me to put foam sheathing on top of insulation between the floor joists. In the second statement, you said no foam sheathing just insulation.

ok...when I talked about the difficulty of adding insulation between floors..it is true...how do you get insulation in the middle of the rooms
even with access on both sides...you can't see that far, so its a wag.
better to use the foam sheating to block off the joist bays at the perimeter of the room.
foam sheating not horizontally on top of insulation...but vertically inside of joist bays at kneewalls.
foam sheating installed on kneewalls and continued down into joist bay to top of ceiling of first floor
go back to the southface pdf and look at #17. this blocking is what I'm trying to explain.
if they had done the drawing at a different angle you would see the pink sheating on the walls, and where it
continues to seal joist bay area.

for the rest of the attic floor, if you decide to pick up flooring and add insulation..just insulation.
it is the upstairs rooms where we are putting an air barrier for the upstairs rooms.

Question 1:
I don't quite understand this 'put the foam sheating BETWEEN the joist bays at the perimeter of the upstairs rooms & air seal. ' Should I put foam sheathing between the floor joists or not?
see southface illustration showing fitting of foam sheathing between joists. in pink.
you are stopping air infiltration into the joist bays UNDER the upstairs rooms. yes, cut sheating 5.5x15 3/4 for 2x6 joists 16" on center.
caulk to seal around edges of each piece of sheating when installed. cut them close to size needed so that they will friction fit into
openings between joists.

2. Question 2:
You recommended JM faced batts and foil faced insulation (TUFF-R, 6.5 R-value 1 inch thick polyiso rigid foam board) for walls and sloping areas. How should the foil facing be directed for both batts and rigid foam board? both facing me while installing it?

foil faces to you...attic side. what we are doing here is using the foil facing of the foam board to
reflect radiant heat OUT of walls. better performance in summer, will keep walls cooler, thus
making it easier to cool these rooms.
foil needs an air space of a minimum of 3/4". by putting the foil facing into the attic space it has
an air space...the whole of the attic. if we faced it the other way...less insulation in joist bay & huge
difficulty in maintaining the air space.
when you look at the wall...from inside the attic...the foil is looking back at you!

3. Question 3:
My knee wall stud cavities are only 3.5 inch deep. Should I still use both batts and rigid foam? rigid foam is 1 inch. can i find a batt that is only 2.5 inch thick?

3.5" will hold R-13-R-15 batts. the former are pretty common...the latter special order. I'd go R-13 & use the higher R-value foam board.
the foam board doesn't go into wall stud bays.
it is nailed on top of faces of studs.
put insulation in stud bays. put foam board over studs
so all you see when you look at the wall is the foam board.
fit pieces close together, use button cap nails to secure,
caulk them for air seal, tape seams of boards.

4. Question 4:
South face pdf page 5. there is two colors of insulation. what is the blue and pink color insulations? blue is batt and pink is rigid foam?

Yes blue is batt, pink foam board. pink is also baffles for air flow in roof rafter bays. foam board seales between floor
joists to under the upstairs rooms.

Thanks you so much. I look forward to hearing from you.
Krishna


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