It depends upon how far into it you want to get, but I recommend reading up in the forums at greenbuildingtalk (dot com). There's a lot to learn if you are serious about building an energy efficient house.

I didn't know that R-13 was even code anywhere these days. Most areas are minimum R-19, which gets you into 2X6 walls. It's vitally important that you pay attention to two things in particular. First, if you are building stud construction, you want foam over the outside sheathing as a thermal barrier. Without it, a 2X6 wall actually performs at about R-13 due to heat transfer through the framing. The other important thing is air sealing, as you mentioned.

If you want efficient and quiet, get a quote on ICF (Insulated Concrete Forms). They consist of a layer of foam, 6 or 8" of steel reinforced concrete, and another layer of foam. They perform at a true R-25 or better, are very air tight, and are exceedingly strong and quiet. The cost might set you back, though.

In the southern US, R-13 is code and generally fine. NOVA is barely the southern US but going down to coastal GA for instance, R-13 is plenty. And don't start talking summer a/c costs. I live in NC and our 5k sqft has about $15 a year in wall heat gain - with r-13 batts.

The way you word the purchase, it sounds like you are buying a non custom house - most upgrades have quite a bit of profit built in so that your payback gets longer. You also don't generally have many real choices.

Insulated sheathing is certainly a big upgrade. IMO, in your climate that is going so far above the usual that it is pretty much all you need.

Quiet=ICF.

Even temps throughout home has everything to do with windows - and not so much the quality but the quantity. A wall of typical dual pane windows will feel a little chilly when it is 30 degrees outside. Similarly a West facing wall of windows will feel hot in the afternoon.

As noted by the previous poster, R-13 is pretty much the rule in the southern US. See here for which Code applies for all US States.

That includes Virginia, where IECC 2006 is mandatory statewide.

This study from Building America specifically deals with a Virginia home in your mixed humid climate and details projected energy savings.

However, expecting a tract builder to upgrade beyond their accustomed standards and methods may be unrealistic.

Build Tight and Ventilate right. Zip is a great way to get an air tight shell. I would pitch for as much insulation as you can get and I agree that continuous insulation will be a good thing. On the ventilate right thing, if you are building a tight home then you need to think about ventilating properly. There are various ways to go about it, but I think that balanced ventilation with an ERV or an HRV are your best bets. Zehnder and Ultimate Aire make efficient equipment. Ultimate Aire is made in the US. Good Luck!

You all hit the nail on the head, this is not a true custom home. Unfortunately I don't have a few million in the bank, and that's pretty much the minimum here for even a small custom place.

So I am dealing with a regular builder and trying to think of things that are close to what they are already doing, but with big benefits. Hence Zip-R vs Zip, since they are already building with Zip it is a possibility to move their install guys up to the R system with 1.5" of insulation. The total, if I can get BIBS, should be a total R of 21.5 in the walls (plans are for 2x4 construction and they ain't changing that). Without BIBS it would still be 19.5, and since it would be air sealed it should be effective to close to that 19.5, though I think a BIBS install would probably be better since it fills voids more. Of course I might be wrong, but based on what I have seen in the regular insulation installs... Yeah bibs seems like it has a base skill level, but once you master that every spot is the same. Fiberglass you need no skill to get it in a perfect spot, but anything else and it gets screwed up fast.

I am a bit concerned about bibs and the vapor barrier that is the insulated sheathing. I don't believe they put on an interior vapor barrier, and the stuff used to hold in the cellulose is permeable so it SHOULD be fine by what I've read. Unfortunately this is a bit of a drinking from a firehose situation though, so many viewpoints and technical documents.

ICF isn't going to happen though, would love if it could, but small changes where the process is similar is going to be difficult enough.

ERV/HRV depends on if they really can make the house tight or not. If it is really below 1.5ACH, then yes. My guess is it will be over that so an ERV/HRV might not make much sense. I'll make that determination when I talk to the builder.

Windows are a different story entirely. They are using MI windows with low-e coatings. Single and dual hung.

I was going to ask to see about upgrading to the MI windows with argon and the sound control internals. It is an option on their regular windows. (laminated glass, two different thicknesses of glass and a sound insulation separator in the cavity,)

Best thing you can do is get away from anything MI in windows as they are all garbage. 99% of builders grade windows are and they are something that you do not want to replace in short order.

I'm well aware, but I'm also not able to afford getting a house then replacing all of the windows again in short order. I'll check to see if there are upgrade options on the windows at build time, but many builders hate doing that from my understanding.

That being said, I've seen a hundred posts stating "MI is garbage" but only specific proof on certain windows built in a specific time period (the class action suit). Then it was due to incorrect use of a foam piece in the construction of the windows and has been corrected.

Everything else is just from opinions or information about what MI produced in 2001 or so. What current information do you have that would make me run away screaming from MI?

I have been in the window door door business for 30 yrs. MI windows are poorly designed, with very average at best air and water infiltration numbers, poor quality control and last but not least poor service for their issues when it is required in the field. The next window pro you see who will recommend your using MI will be one of the first to my knowledge. Pretty much any of the windows available thru a box store or a building supply are builder grade (there are exceptions of course) and in my opinion and the opinion of most pros a poor window choice.

I'm in a different climate...the R-13 walls area!

IMO your best investment with walls is
to use foam sheathing on exterior of walls.
there are two types of foam sheathing
rigid sheathing @ R-7 per inch value
and not so rigid sheathing @ R-3 per inch.
getting more R-value for the install would
be my recommendation. plus the higher
R-value sheathing is easier to work with.

when installing foam sheathing caulk
at top of sheathing to top plate of wall,
and at bottom to sole plate of wall.
tape all seams. ( I use button cap nails
to install...and follow nailing pattern
of 6" on edges 8" in the field)

prior to cladding install any holes should
be sealed.

even with R-13, adding the R-7 sheathing
will increase overall value to R-20, plus
sheathing on exterior will eliminate thermal
transfer through the studs.

air sealing is important. and it starts early.
sole plate should have Sill Seal between wood
& slab. at the very least...a double bead of caulk
at sole plate to slab.

sheathe walls with foam board, use conventional
insulation in walls and air tight drywall to interior.

http://www.buildingscience.com/documents/information-sheets/air-barriers-airtight-drywall-approach

the sheathing on the exterior of walls ADA to interior
and you stop air movement through the insulation
in the wall. then...you get the full benefit of the
R-values. insulation slows air movement...it doesn't
stop it.

visit southface inst and google air sealing pdf's.
some great detailed information.
building science website also has excellent info.
look for info from sites not selling products for
unbiased info.

find out how much your builder is willing to do.
ask if you can attend to some of the pickier things,
it never hurts to ask, and then you'll know.
it can be an educational experience for the both
of you, if you approach it the right way.

know that if you invest in a tight house, then the
hvac system should be sized for the tightness of
the house & any other upgrades you've incorperated.
rule of thumb sizing isn't a good thing.
efficiency is about trade offs. invest in air sealing
& trade off is less tons of hvac is required.
this might enable you to invest in more efficient
hvac system. and it isn't too early to start educating
yourself about what type of system you want.

fwiw..I've seen issues with BIB's a few times.
if stud bays are overfilled..it will show when sheetrock
is installed. it takes an experienced hand on the
insulation to fill to optimum R-value without causing
buldges that will cause sheetrock to wave.

and for windows...good unbiased, shop any brand with
info from this site:
http://www.nfrc.org/WindowRatings/The-NFRC-Label.html

my own pet peeve is recessed lights. instead of IC rated lights pay to upgrade to ICAT for all of house...including
any exterior recessed lights. Insulation Contact Air Tight
about $15 more per contractor box of 6, but $15 per light
to retrofit to air tight. believe me...the electrician won't stop & say...oh these IC lights are for patio & those ICAT are for master bedroom...whatever is close at hand...that is what
gets installed. if it is wrong...oh well...
invest in all ICAT.

best of luck.

I know all about can lights. Ugh, I replaced all of them in my house with ICATs. They were like open windows straight into the attic, so much so that the insulation blew off of the old IC ones.

While I didn't mention it, they are non-negotiable in my discussions.

millworkman: Ok, so if MI is not good, what do I do if the builder says no? Do they have good versions of some of their products or are they just bad from start to finish?

btw, I'm still a bit confused on MI windows.

http://www.mienergycore.com/uploads/docs/1386351460-442b2ac01b90255dd/MI_EnergyCore_Arch_Packet_12-6-13.pdf

That, with their newest model, shows pretty darn good specs. Low air leakage (below the .1 minimum rating by the standards org) in many cases. STC is pretty good as well in the laminated glass varieties...

Sorry if I am beating on this issue, but I need information I can take to the builder and bargain with if MI's new windows really are a bad deal. Just saying "some guy on the internet tells me they are bad" is only going to get me so far. :)

While this is approaching OT, any upgrade beyond MI will be cost prohibitive.

While I certainly appreciate the opinion about MI windows, there is a reason nearly every builder uses them. Since you aren't building a full custom home, it doesn't seem to make financial and practical sense to pay a lot of money to upgrade one portion of the house.

I think my 40 MI windows were $10k and a typical branded window would be $30k. Now take a large builder and add the additional headache fee for switching what they use in 99% of houses and you can add another $10k.

While you are appropriately focused on air sealing and insulation, you are somewhat limited by not being custom.

Most any window will have similar specs when they are new, within a given set of specs (double pane, argon filled, low-E, etc.). The difference comes down the road, when they warp and sag and shrink. It was a major shock to me when I read about the relatively short life-span of windows these days. I grew up in very old houses with their original windows. Nobody replaced windows unless they wanted to upgrade to more energy efficient ones.

We went with middle-of-the-road windows (Marvin) based on a lot of research. They certainly look a lot better than builder grade windows; time will tell if they hold up well enough to be worth the considerable extra cost.

living in an icf home, I can vouch for the advantages of it. Super tight (tested out just above 1 ach @ 50), quiet, my version averages about an r30. In a high heating climate with the average temp in the lower teens this last month, the 3800 sqft home cost me $62 to heat. However I also have triple pane windows, solar gain desined and a spray foam attic seal with an r60 blown on top. Which leads my to my next question. You mention ZIP and air sealing the walls and rims, but haven't mentioned the attic. You lose large amounts of heat through the attic, so this needs sealed up just as well as your walls.
For windows, the first thing you can do is get away from single and double hungs, especially with cheap windows. You can not get a more leaky window. Beyond that it is what the builder is willing to do, and for what price. Triple panes will also add to the sound qualities, but I imagine are not an option for your build.

BIB is getting to be very common around here, and if done correctly do not affect the drywall. it is typically what I spec for new projects, and avoid batts at all costs.

the first thing you can do is get away from single and double hungs

I've always used casement windows.

BTW, how many decades will the payback be for upgrading to triple pane windows in a moderate climate like Virginia?

**
Six years after I built a custom home with low-E coated argon-filled double pane wood windows, the second owner scrapped them for standard vinyl as he didn't like the idea of repainting the wood from time to time.

This post was edited by worthy on Sat, Dec 21, 13 at 19:26

Payback on triples for them? Probably 30 to 40 years at least so double the life of the window. On my zone 6 it was about 22 over duals mainly due to the solar house design. Had i not had the solar design, payback would be closer to half. Dual pane were actually better performers for me in the calcs on the south at mid .55 for shg but was still able to hit .45 with the right triples. However it's not always about payback. I went with them because of some of the large windows next to sitting spaces (no cold radiating off the glass) and also for sound. My window package was only $13 k with the triples so the difference was only a few thousand in my situation. Had it been more such as 5 k and more, probably would have not gone that route. My recommendation of triples for them would be mainly for sound and not energy savings, but stc are even a big stretch on price for what the gain would be.

This post was edited by lzerarc on Sun, Dec 22, 13 at 11:38

to focus back on my original questions... I can't do ICF, that's not an option. The type of construction is fixed and the builder is not a custom builder.

I have to keep the options and suggestions down to something that can be accomplished without any changes to the basic design considerations, hence windows, insulation and limited sound abatement. The house would be in northern va, so a mixed climate.

I don't have a choice on MI Windows, so I have to do the best with what is available. My research so far shows they have a few different lines, the "best" line appears to be their EC line, vinyl extrusion with a honeycomb structure in some of the sections.

Anyone have actual experience with that line? They have a bunch of "best product" awards, which mean nothing. I see lots of negative posts here from the same people over and over, and they may be super knowledgable but I still see no information that DIRECTLY shows me something I can bring to the dealer about these windows.

The insulated sheathing vs non insulated (zip vs zip-r in my case) does this require any major changes in construction? Other than taking into account the extra inch and a half used? Anything else I should think about?

The airtight construction technique looks to be using caulk around drywall and floors. I'm going to see what they think about that as well as spray foaming the areas between floors and caulking/foaming all penetrations etc.

Should I insulate under the slab? I'm guessing no, but I just don't know. Basement is not a walkout, but it will be finished.

Just a question, as I am learning for future build...
Why would you/your builder use MI windows when there are Class Action lawsuits against them for windows that did not perform?
Thanks for any info

ilmbg, very simple, most builders don't care as it comes to the almighty dollar. That and the fact that that this is the brand window his supply house carries.