Thanks, David, for the reply. We figured we would phase LED lights in as time went on, starting with places like the kitchen where our home would be active the most.

I'm not sure what you mean by "getting away with woodburning alone." Are you referring to passing code? We have no codes or inspections in the area where I live. Our current home is heated by a woodburner alone, with no source for backup.

As for our access to natural gas, the oil wells near our home are not very reliable and we would have to depend on a backup much of the time if we went the natural gas route. And, by this, I mean using the oil wells on our property and just paying oil head prices.

If we had to pay more than oil head prices, our heating bills would really be high and we would certainly be looking into advanced framing and insulating.

However, with woodburning and geo on the plate, we were just trying to decide at what point our head's would hit a "glass ceiling" in terms of saving and efficiency. Does that make sense?

Also, westiegirl, air to air heat works pretty much the same as geothermal, except compresses the heat in the air, correct? I might be summarizing this wrong, but that's what I got from energysaver.gov... =)

And, to edit, we do have "codes" for insulation minimums, etc.. just no inspections and codes that wouldn't allow us to use woodburning heat as sole heat source. It is done all over my region. Hope that clarifies what I meant to say!!

There is no reason why you can not use wood buring as your main source of heat. A lot of people do it. Your points about the extra work is something to really consider...you are never getting younger....

Air to air hp work the same as the geo pumps (also called ground source heat pumps). Geo pulls heat from the earth, air source pulls heat from the air. Geo's plus is it can produce heat through the entire winter, air source heat output is directly related to the exterior temp. As the temps drop, the heat output drops. Not really the best thing for a heating options...
However newer heat pumps rival geo efficiency, especially when geo's loop pump electrical usage is factored into the mix. Air source heat pumps are capable of producing heat below freezing, with a typical cut off point usually in the mid teens to low 20s. Some of the mini split units are capable of producing heat with a -14 degree exterior air temp.
With an air to air heat pump, you would need a back up heat source when the temps drop. This can be an electric heat strip in a blower unit, or is can be a gas furnace. There are also hydro units run on electric boilers. Your installed cost should be roughly half of a geo cost, even at around $25k. Remember, the tax credit is great, if you get it, but you still have to front the 25k and then wait around for the rebate later, assuming it comes.

Like I and others have mentioned, your shell is your first step in saving money. Shell improvements costs are typically quite low for the benefit you gain from them.
For instance my double stud, r40 walls with an r60 roof adds about $4k to the entire house project in materials over a code min. home. But I only need a 2 ton heating system for my main level and basement. This saved around $3500 on on equipment compared to a 4-5 ton system a house of this size would normally need. So $500 more is all my super insulated shell costs. My climate is colder then yours, and with an air to air heat pump with an electric heat strip backup, my total estimated heating and cooling costs for the year is $580 @ $.109 electric rate. This does not include the rate cut we get during the winter, which drops it down to $.06. That works out to be less then $50 a month and only spending $500 more then a CODE MINIMUM house. Also it qualifies for Energy Star 3.0 rebates as well as local rebates from utilities companies, which total about $5800. A code min. house would not qualify for any of this. Thus, my "above cost" for a super insulated home is -$5300! Obvioulsy results like this are based on your utility company, house size, etc. But the point still stands. Put the money in your shell first. Then let the mechanicals work for the heat and cooling loads. DO not overlook rebate options and factor those into the costs as well. Speaking of LED, a lot of power companies are offering rebates on them too, as well as CFLs.

To add to the above comments about air to air heat pumps, our personal system has the cutoff point to switch to our backup furnace at 4 degrees. We have played around with this a bit this winter because DH thought it would be way to low, but our friend/HVAC contractor told us that his home system was set at 0 degrees.

Our thermostat also has a bunch of settings that I don't really understand, but basically if the heat pump can't get the house back up to the temperature we have it set at within 1 hour, the backup furnace also kicks on. Our propane furnace has only kicked on a handful of times this winter. The only other propane use appliance we have is our range and our use has been minimal. The coop driver said he would wait until summer before stopping and checking if we need a fill unless we call them.

DH works from home, so we don't have a huge setback on the thermostat set like a lot of folks. When we are home, the thermostat is set at 70 and gone/sleeping at 64 (in the winter). For our 3800 square foot home last month, the electric for just the heat pump was $41.00. Our R40 walls and tight air sealing help this tremendously!

"We have the equipment to dig a horizontal loop system, so we are hoping to bring some of the upfront costs down.). "

Deeper is better than shallower.

Boring deeper produces a more efficient system since the temperature is more stable.

You have to dig well below the frost line even for horizontal loops.

Lyn: as I mentioned on another forum, we are very happy with our geothermal. Yes, it did cost a bit more to install. But we are really enjoying our low electric bill. We are all electric except for the fireplace and range. The house is 5200' finished. We've been in our house 9 months, and our propane tank is still over 75% full. Our backup furnace has never kicked in, and we are in WI. But our house is very well insulated. The builder did everything right. -As I told you before, we went away for 3 nights, set the thermostat at 50, and it never got below 58 degrees. The system is super quiet. One of things we considered when making our decision was the cost of LP versues natural gas. We don't have access to natural gas, and LP is 3-4 times the cost of natural gas around here. One other thing to check on is reduced electrical rate, however I don't know what the rate is.

I know you are considering wood, and for us that would not be an option. DH and I are in our late 60s, so keeping a wood burner going would not be in the cards for us. However, we have friends our age who don't mind it at all.

west-
you give great real world experience that should not go unoticed by the OP! And a good reassurance for me since you are located a couple hrs away!

joyce- can you elaborate on shell type as well as electric bill if you would not mind sharing?

"For instance my double stud, r40 walls with an r60 roof adds about $4k to the entire house project in materials over a code min. home. But I only need a 2 ton heating system for my main level and basement. This saved around $3500 on on equipment compared to a 4-5 ton system a house of this size would normally need"

Lzerarc - Don't want to hijack this thread but it has been very insightful as we are working on this right now with our new build. How do you go about determining your new heating system requirements with the beefed up insulation and tight shell?

Lyns., have you thought about ICF?
The main dif in cost from a ASHP to a geo is putting the pipe in the ground and the desup. Since you are making the trench(you could also put the slinkies in), that would save thousands!

Del- I have various modeling software and programs that i use.

My issue with wood alone is that it would not pass inspection here - not an issue for you. I am surprised by that since code and inspections are often designed for the next owner. Since that heating system requires manual labor as an input, it certainly isn't for everyone - hence the code requirement. Just something to check on - obviously old houses passed code at a different time. Another thought is that even though you don't have inspections, your bank (if needed) might have them. Also - there might be a code - not enforced by inspections. Whether that is an issue, I don't know. But it could affect the future sale of a house if it was built not up to code.

I am going to give a counter argument to Lzerarc, not because I disagree with him but just to give another side. A/C is less dependent on wall r-value. If you take your shell down too low, you will still need tonnage to cool the house. Cooling has a lot to do with window size and orientation. Cutting this is not a compromise that is always available depending on view etc.

I suspect in your location, an r-40 wall will make you cooling dominated for size. This means your equipment savings get diminished. If you can orient most of your windows to the South, then this in a non issue.

And what isn't figured into his costs are that he lost square footage with the thick walls. Someone did the calcs and it was 120 sqft (but I don't know what house size they plugged in) and that can represent $6k in costs based on $50/sqft for foundation/siding/roof etc.

If you go with woodburning, of course spending money on a shell is harder to justify. But it does make the house more comfortable.

At some point, there is a lot of talk about saving very little money....

As pointed out above, the biggest energy savings payback comes from the design of the shell, including siting, fenestration, overhangs etc.

Indeed, the Passiv Haus standard aims at eliminating heating/cooling systems with that emphasis.

But short of that standard, the choices of methods of interior climate control have to be integrated with the design. Consider, for instance, solar water heating systems.

Here's a real world example of energy efficient building in a cold climate completed by Building Science Corp. The project was designed to achieve an 87% source energy reduction compared to the 2009 Building America benchmark.

I agree that if you take the same foundation footprint of a home and turn it into a double stud plan, you will lose some interior square footage. However, I designed our home from the inside out. We determined what size rooms we wanted and that translated to the size of our footprint, so I don't feel like we compromised with a "loss" of interior square footage.

Yes, we did have increases in the size of our foundation and exterior materials (siding/shingles/etc), however they are very minimal based on the fact that our exterior walls went from 6 inches to 10 inches. Basically our footprint was extended a total of 8 inches north/south and 8 inches east/west. Because we built on rural acreage, the footprint size was not an issue. If we were trying to fit this house on a typical suburban lot where many houses are built up to the setbacks, that might have been a different situation.

When we went over the different options and costs with our contractors, double stud was actually the cheapest way for us to go. 2x6 with spray foam would have been more expensive in our situation (other people's experience will vary I am sure). No contractors in our area were familiar or experienced with either SIP or ICF construction. When we talked about putting rigid foam on the exterior, the details on window flashing and fastening the siding would concern the contractors and their labor prices went much higher and we had no assurance that the detailing would be done correctly. Double stud required almost no learning curve for the builder and made it easier for DH and I when we were running electrical later. I also personally like the look of my wide window sills as an added benefit! This photo shows how the extra depth looks on our windows. We are still working on baseboards, so please ignore the unfinished items.

David
While are points are valid, as you know it all starts with the correct design. You can take most homes that are 2x6 and add foam without much fuss. However going double stud has to be designed for. THe loads on my 3200 total conditioned sqft home in zone 6 with 7200 HDD is 19k heating and 12k cooling. Glass is about 9% south and about 8% north, nothing on the east and west. Overhangs are sized correctly. Double stud does eat up a few more inches, correct, however the layout of the home is used to maximize materials. Use full sheets with little to no cuts for sheathing, ICF forms, etc. Layout and planning results in reduced costs (not compared to a code min. as I pointed out however, rather costs not as high as one might think) for something like this.
As mentioned, the numbers were an add above a code min. home (r13+5 ci). This would include potentional losses due to slighter larger roof and foundations.
Sure you can do a code min. that also makes us of maximizining materials, but on the flip side, that adds additional finished square footage, which also needs to be conditioned. I would argue the biggest energy saving step is to reduce the total home size in general. 3200 is big IMO, but half of that is below ground as well.
Double stud not for everyone and certainly not for all climates. But then again, I never recommended to the OP to do double stud either. I was simply using it as an example of how shell improvements can save costs in other areas.

There are other reasons besides simply attempting to reduce gas/electrical costs to building really efficient.

My wife and I are downsizing and planning a "grand" move to NC. I have been in the construction/engineering business for some time and sense that a new build in a semi-rural setting will be well suited for us. My wife and I value the comments and suggestions of those who have previously contributed on this thread. I do have some concerns that may warrant some discussion. When we speak of "geo" do we need to explore all potential risks and hazards to the system surroundings in particular the area underground? For instance- isn't this another source of heat pollution? What if all homes, both new and existing, with a heating/cooling demand were to be outfitted with a geo system by say 2025? What would our subterranean ecosystem look like? How would the surrounding dirt,rock and water respond to the ever changing temperature gradient(s). Would we see adverse changes to our water reservoirs and aquifers? How would we establish system boundaries that would be exclusive to each residence and not interfere with adjoining neighbor's systems. How would we prevent and control spills and leakage of antifreeze and spoiled loop water? And we can almost predict a certain bio-hazard from newly introduced or adaptive/mutated bacteria and microbes that will thrive in this new environment. I think this system needs further studies and management before we allow mass implementation. In the meantime I think I will leave geo out of the "loop".

Great discussion here. Keeth, you bring up some good points and they can fall under two types of geo/ground source heat pumps GSHPs.
Many existing systems are the open loop type that bring regular ground water up through a well and then send it back to the ground or let it flow into a nearby water shed. Most of the industry is moving to closed loop systems with refrigerants.

The only real concern in your list is the closed loop refrigerant being lost to the ground water. Considering that most loops systems have no couplings or connections more than a couple feet below the ground (manifold) and that the current refrigerants are fairly benign, I dont think its a very big risk involved. The amount of pollution that GSHPs prevent is much greater than this risk in my opinion.

Lzearc has a good point about COPs not being accurate but I think this mainly applies to the open loop type which have energy intensive pumps. The newer closed loop systems, which are slightly pressurized, do not have nearly the energy consumption and I would guess that their impact on COPs are no more than a .5 point. Considering that some of the newer systems have COPs of 6, GSHPs are one of the most efficient and cheapest to operate mechanical systems available even when compared to natural gas for heating. Of course, one of a heat pumps biggest advantages to anything else is that they can also provide cooling.

That being said, the more you improve the building envelope, the longer the payback of GSHPs and considering that your envelope is the most permanent part of your home, the most difficult to correct and improve and does not require maintenance I would upgrade the shell and in your particular situation, probably go with Air Source with electric backup. I love the idea of a wood boiler but at 10k extra I would rather put that extra 10k to a PV system or GSHP which would have year round benefits.

Coincidentally have a recent blog post on GSHPs for those interested and wanting to see some simple diagrams of the ground loop options mentioned.

Here is a link that might be useful: Ground Source, Geothermal Heat Pumps in Asheville NC

Thanks to everyone who has participated in this post--both with helpful information and provoking questions! I am very excited about what I have learned!

I have to admit my ignorance! I started this thread without a hint of knowledge about the possibility of using air to air versus geothermal and I am excited about what I am finding.

Of course, this opens up more questions for me. =) When I shared what I learned with my husband, he asked about the difference between framing with 2 x 6 versus double stud. I gather that this is a largely discussed topic, but if someone could give me the summary, I'd appreciate it!

Also, is "ICF" insulated concrete forms? I believe my husband had looked into doing this with our basement. Could anyone provide any additional information about the cost/benefits of doing this with our basement?

Now, the air to air (hp= heat pump?) can also provide cooling, like geothermal? I believe westiegirl said that their unit provided cooling, as well. What about serving the needs of a hot water heater? Does the air to air function this way, too?

As for windows, our plan is to have many.. I know that windows aren't always best for insulating a home, but we are setting the house on a north/south orientation and hoping to use the sun to our benefit. How does this work, however with deep porches (10' on south side, 8' on north). Would I need to consider different r values for each side, low e all around? This part of the conversation is one that I haven't researched much, so please forgive my apparent ignorance!

And, for more questions (!), how hard is it to find builders who are competent in this sort of building? What about finding HVAC contractors who can supply and maintain the air to air unit? Geothermal contractors are numerous in my region, but I'm pretty sure that I've never heard of anyone supplying air to air.

Another person posted this question, but for those of us who don't have software and formulas at our disposal to figure out what sort of tonnage our heating units need for our homes, how do we ensure that our super-insulated homes are using the correct system size (decreased)? Or is this something that I should trust the installers to know?

I apologize for the amount of questions! I'm eager to hear back from you.

Lyns

Lyns06,

I will try to help with some of your questions and I am sure some of the professionals who are much more knowledgeable than I can help with info as well.

I can't imagine finding a HVAC contractor who can install an air to air heat pump would be difficult. My husband and his friend who is an HVAC contractor did the entire install themselves. In our area of central Iowa these hybrid systems are actually quite common because the upfront costs are much more reasonable than geothermal. While we love our heat pump, one thing my husband and I were discussing today is how the air that is put into the house through the vents is much cooler than if you are used to a traditional gas forced air system. My understanding is that this is the same with geothermal as well. In my picture above, there is a floor vent right next to the smaller plant. DH and I were talking about how the plant does fine with the air blowing against it all day because it is not as hot as a traditional system.

When we were deciding if DH would handle the HVAC install or sub it out, any contractors that we contacted performed a manual J calculation to determine how to size the unit(s). My understanding is that performing a manual J is somewhat of an art form and you need someone who understands the standards/levels of insulation and solar gain to which the house was built.

I am not sure what questions your husband has about 2x6 versus double stud, but if you would expand on your question, I would be glad to try and help. Our home was basically built with one outside 2x4 traditional wall, we then have an approximately 2 inch gap and then the interior non load-bearing 2x4 wall. There are different ways to detail the top and bottom plates, but ours was joined with a 2x10 on top. This was for the convenience of the framer, but if we had gone with separate top plates, the thermal bridging issues could have been reduced. Our only other complications with dealing with the thicker wall cavities were the jam extensions in the windows and doors.

Good luck, researching and informing yourself before you start the build process is the best thing you can do!

Air to air is much more common and simple than geo. Every HVAC contractor will have done it. An air to air HP is just a normal a/c unit that has a reversing valve to heat the house.

A typical air to air heat pump will not do anything with hot water but you can get a separate heat pump for your hot water.

You don't want such deep overhangs on the south side although it does depend how tall the porches are. You have a lot to learn about windows. There are two separate issues SHGC and u-value. They are different numbers and you always want a low u-value (which is 1/r-value), but SHGC depends on whether you are trying to heat the house or keep it cool.

You have very little hope in finding a HVAC contractor who will design a system that adequately compensates for a good shell.

As far as double wall - it is an uncommon but inexpensive way of reaching a high r-value. It involves building 2 walls out of 2x4s on a 2x10 base. Then your insulation is 10 inches thick with a spacing in between the framing to serve as a thermal break. The other option is a 2x6 wall with foam sheathing on the outside. Both are great options with the double wall being a little overkill in a lot of climates (including probably yours).

1.) Double stud walls, if incorporated at the design phase, are one of the cheapest ways to boost the energy efficiency of your home. One of their benefits is that you can break the thermal bridging, that is the heat transfer, that occurs through the framing itself. The heat transfers through the interior wall framing and then hits the air gap that Westiegirl mentioned. That air gap is filled with insulation. On the other side is the exterior wall, whose framing connects to the exterior. So you see the path that the heat was traveling through, the path of least resistance, the path through the framing rather than through the higher r-value insulation, is broken.

Another feature is the ability to put most or all of your wall penetrations for plumbing and electrical into the interior wall and then vapor seal the exterior wall and not have to contend with penetrations in the barrier.

Then there are the aesthetic pros and cons. A feature that I like is the wider windowsills but that comes with a "light tunnel" effect, but as has been noted that effect can be minimized by rounding the corners.

2.) In terms of your overhang design, it might be worth spending some time on this site. Play around with the sun angle model and see how much sun comes into your room on any given day of the year and how far it penetrates into the room. You can tailor your overhang to find a pleasing optimum. You can also see the effect of the sun on your west and east and north windows.

Be sure to look at the top of the page for the other computer simulations available and try some of those out as well.

air to air hp will be more common then geo hp, and about any hvac guy can help you out with one. They are not quite as specialized as geo systems.

This hvac contractor, like westi mentioned, will be responsible for calculating your loads and estimating costs. However, to be completely honest if higher efficiency is something that is important to you, it will be in your best interest to work with a designer or architect that is familiar in the various ways to design a house to maximize things in these areas. They should have programs to help aid in the pay offs of certain decisions, as well as estimated cost differences between various proposed wall stackups.
With that being said, you are correct with ICF. Do some research on ICF and find out the pros and cons of the system. They are great at providing a strong, quiet structure with a dramatically reduced air infiltration rate, however typically in heated climated do not perform much higher then the thickness of the eps foam used. They also come with a 3-5%+ premium over a typical stick house in cost.
Framing a double stud wall is basically exactly the same as framing a 2x6 'typical' wall...you just do it twice. As westi said, you can connect the inner and outer wall with a solid member, however one of the biggest features is the thermal bridging the wall prevents, so I like to keep them 2 separate walls with roughly a 2-3' gap between them. The walls are simply attached together towards the top and bottom with scrap osb/plywood from stud to stuf if you so desire. I also like to box out the window openings with 1/2' osb/plywood to tie the 2 walls together and create an air tight window opening.
2x6 walls, while allowing additional insulation, do not address thermal bridging issues in the wall. This reduces the performance of the insulation. Adding exterior foam to 2x6 walls reduces and eliminates thermal bridging at the studs, heads, sills, rim joist area, etc. However the details for attaching siding and water shedding has to be well thoughtout, designed, and built. The details in foam exterior walls is more complex compared to a double stud wall since the double stud wall is, afterall, just an exterior 2x4 wall built the same way all walls are.
However when you are punching a large amount of holes in your shell, it really starts to reduce the effects and would make me think twice about either the size of the windows or how crazy to go with the wall insulation. An experienced designer can help you walk through that issue.
I would recommend you head over to Green Building Advisor and do searches, read all of the great stuff they have on there. It will most likely answer most, if not all, of your questions.

Here is a link that might be useful: Green Building Advisor

Thanks, everyone, for the informative and hasty responses!

I'm glad to hear that air to air is something that HVAC contractors will be familiar with.. I'm still not sure why I haven't heard of it, or if I had but perhaps just didn't understand!

I'm gaining more of an understanding of the framing. That is certainly my husband's forte; he was more uncertain about which method was better-- 2 x 6 or double stud--since he's looked into both methods, just never came to a resounding answer as to which is superior.

As for the interior jams, I think that your windows look lovely, westie! I could see how the cost of trim could increase with the added depth, but I'm sure that one-time-cost is negligible when factored into the savings.

For the windows, living in N.E. Ohio, where the winters are long and dark, I decided that one of the most important features of our new home was windows. The long winters are hard on me emotionally; I suffer from SAD and I'm hoping that light will help my mood! So, rather than moving south seasonally (alone, because my husband would never leave! =) or taking meds, I am opting for a lot of light! I'm sure it will have a negative effect on our efficiency, but how much so?

I have already considered mostly going large on the south side, since that will be where most of our activity will occur in our home. As david_cary mentioned, I do have a lot to learn about windows, but that's my plan! I appreciate the links, alexhouse and lzearc, and will spend some time visiting them!

As for ICP, are they as effective when just used in the basement, rather than the entire home?

One more question: I was visiting the EnergySavers.gov website and they implied that air to air is mostly for warmer climates. I know that Ohio is not as frigid as many regions, but I wouldn't consider it a "warmer" climate. How often should someone in my region expect to have to rely on back-up heating in my region?

Thank you, again, everyone who is providing your time and knowledge! It is very, very much appreciated!

No one can answer your window questions until you dig into the sizes, floor plan, overhangs, etc. Going triple pane will make them more efficient, but also cost more as well. But triple pane also helps to reduce the cold currents that comes off of cold glass. Typically the inner pane of triple pane windows is withint 5 degrees of the interior temp, hot or cold.
Air to air hp can work in most climates. However since they do produce less heat when the temps drop, you do need the backup heat. Your back up heat will run as often as...well....it depends on how efficient your shell is! I know of homes where are in colder climates then yours and the backup comes on only a handful of times in the winter, typically in the middle of the night when temps are lowest.
Energysavers is an ok website to throw some ideas and concepts at you, but it really does not go into any detail on any of the subjects. Check out the sites we offered you. You will gain FAR more knowledge then anything the government stands behind ;)

The older type of heat pumps were for warmer climates. We had one in our older Florida home that was only good to around 30 degrees. These new types have been engineered differently to allow for colder operating temps.

In case you are interested, here are a few photos of our walls in the framing stage that show how they were constructed.

Thanks, westiegirl, for the images! That really helps me to have a greater understanding. For some reason, I envisioned the 2 x 4s being staggered rather than put together with the 2" gap.

You mention that you have a "newer" heat pump, could you tell me what it is called? Is it specifically for cold climates? Or, is it just that the air pumps have been improved upon so much as to do better in colder temperatures?

And, yes lzearc, I'm digging into the websites provided and finding a wealth of information! I've also been searching some previous threads and have found more helpful information from your previous comments that are further helping me in my research! The knowledge that you have provided this forum on this topic is invaluable. Thank you.

I'm eager to keep finding answers. I'm hoping that I can come to a decent compromise between light and energy efficiency. I feel confident that since we're still in the "planning" stages of our build that we can come up with something that will manage both of these desires!

Thanks again, guys!!

We have the Lennox Elite series heat pumps. We have two of them because we have a 2 ton system for the bedrooms and a 3 ton system for the living areas. Our home is 3800 square feet finished on 2 above grade levels and 2400 square feet in an unfinished basement.

You could build the walls with the 2x4s staggered, however because of the two inch gap for the thermal break, we didn't have a need to. Also, our framer found it easier to basically build two "twin" walls on the ground and tip them up.

Love this thread, we are building in about two years 3ksf on 1 1/2 acres. Water in our area runs about 150-200$ a month "some 500$ during the summer"! So many people are starting to drill a 11-15k well and getting an nice 300ish RO unit for drinking/cooking water.

I will 2nd or 3rd natural gas with your heating, but check your area. We live in the south, but even us are consdering electric coils in the living and masterbath on timmers either under hardwood or stained concrete. I imagined that with a natural gas fireplace would be awesome. To cut cooling down in the summer, I know a ton of people that run window AC units "even on much nicer homes" if they can be somewhat hidden. Its a great way to save serious $ in the south.

Don't underestimate the windows, from everything I have seen over the years the window areas are usually the #1 reason for heat/cooling loss. I would also focus on more facing south ward if possible, I am planning on using tinted windows on the front 3-4 and a french door, 3, and accordia slider doors on the MIDDLE back not tinted.

You should look into dogtrotting homes. I plan on with the large front and folding back door, having a large breeze as the weather here is nice 3-4 months out of the year. I am just guessing but right now 200-300 yearly savings, I do the same thing with two cheap box fans run on the windows in our rental house.

You suffer from SAD, I think I have a really cool solution,

Check out sola tubes, they are like skylights but with german reflectors. We are planning on putting 3, one in the kitchen, one in MB, one in GB. Some are controllable, and come in all different sizes, "they would save some on lighting as well MAYBE as you wouldn't need as much".

I would do heavy carpet in the bedrooms and possibly HW in the whole house, I know it would help insulate even if just a little if the buget allows. In the south, stained concrete is taking off as 80% "total estimate" of annual engergy is lost during our "6" month summers.

The way I look at it, I "and most people I think" are much more comfortable when their feet are cold in the summer and warm in the winter.

Something everybody seems to not talk about/overlook now days is home mainteneance, if your cleaning those really elaborate tile showers in all 4 bedrooms all the time, or having to pay for a maid, then your using more cleaners, spending more time, etc, and that equates into $. After all time = money, and who wants to spend time cleaning.

I prefer cooking with gas, will use gas heating, and two front outdoor lights.

I have been looking into led solar powered landscape lighting, and it seems to be worth it vs low volt finally, but should cost 300 ish on a nice system for 5-10 lights.

With you needing more light, I would say a couple of sola tubes, coupled with led lighting, would be what I would do. check out Chinese led lighting on ebay, like ledhk. You could get some 3k yellow/reddish tint leds "they come in every color" bulbs for around 10$ a pop and put them in the rooms you use lighting the most.

basic information:

for information common to all windows-
www.nfrc.org
what the sticker that is common to all windows looks like.
http://nfrc.org/label.aspx

solar heat gain coefficients (SHGC) of .30 or less
U-factor .30 or less.

if the windows you are looking at do not have this independent verification..look at different windows.

in general people do not do double walls in my area.
putting R-7 foam sheathing on exterior, conventional
insulation in walls, and air tight drywall to interior.
R-7 plus R-13-15 in wall for R-20-22 in a 2x4 wall.
2x6 would be R-19 plus R-7.
air sealing of sole plates and around windows and doors
stops air movement through insulation, and the foam sheathing board provides a complete thermal break.

of course we do a lot of plywood sheathed walls for
hurricane strength too.

hvac systems..
I've had a lot of clients start out with wanting to
do geothermal, but in the long run opted for heat pumps.
costs for geo are really high here compared to other areas.
it gets confusing all the names that mean the same thing.
geothermal, ground source heat pump...
sometimes its a name game!

air to air heat pump, air source heat pump..all the
same thing.

this is just basic info so you'll have an idea of what
is what.

these units are 3 pieces, condensor which goes outside
air handling unit W/coil & heating system that goes inside.

heat pumps work year round.
a/c in summer
heat in winter.
the furnace has back up heat strips that are activated when temps drop below 30 degrees.
there is also a defrost mode for the condenser.
these systems are efficient.

straight a/c and electric heat. condensor is a/c
ahu w/coil, heating system. all heat is heated by heat strips
this is an expensive way to heat. (like the most expensive)

then there are hybrid heat pumps
condensor is same, but when temps drop below what hp
can handle the back up heat is gas.
efficient.

or a/c with gas heat. also efficient

that would be where I would start.
determine what system you would choose.
based on your fuel type.

the efficiencies of the different systems
will also depend on the efficiency of equipment.

13 seer a/c or hp is least efficient allowed by law.
invest in more efficient units
heating efficiency for hp is determined by heating seasonal performance factor (HSPF)

for gas furnaces 80% afue (annual fuel utilization ..something)is mininal efficiency
more efficient are 90%+.

these again are basic numbers for efficiency
all brands use these numbers.

then comes two stage, variable speed, etc.
but step by step...

sizing and design of the ductwork is as important
as equipment sizing. load calcs and design calcs
should be used for all.

if you do online research, keep in mind that mfg sites
are selling products. look for unbiased, not selling
products like building science etc.
and that what works in one part of the country
doesn't always follow elsewhere.

best of luck.

Thanks for the input, everyone! I'm digging into the links provided and finding a wealth of information.

I have a question for those who have done the double stud framing: Do you use spray in foam insulation? If so, is it just applied to both of the 2 x 4 walls, with the 2" gap left open? Do you spray it in after all of the wiring and plumbing is completed or does that just fit between the two walls (again, I'm displaying my ignorance on the topic of framing! Ah!)

Another question for westiegirl: You mentioned in another thread (I'm not stalking you, I swear!) that, "On our double stud build, we had a difficult time getting an accurate Manual J calculation done. We are oversized with our 3 and 2 ton units and are having to make some adjustments as a result. None of the HVAC contractors in our area had ever seen a wall assembly with as high of R values as we have and couldn't believe that our load requirements should have been substantially less."

Did you use a designer or architect to help you figure out your components? One of my fears is that our home will be properly insulated and it won't be reflected in our equipment we purchase/use. Would I need an energy rather, green designer, or??

Thanks again, everyone, for your replies!

no! DO not use spray foam. Massive waste of money. Instead, an insulating contractor will install a tigh netting on the stud face and then they will dense pack and blow in either cellulose or fiberglass insulation filling the entire 8-12" wide cavity resulting in an r35-40+ wall.
As I stated before, I would highly recommend getting connected with a green designer/architect who has experience and knowledge of the various types of wall systems and can balance that performances with a "just right" mech. equipment.

We used blown in fiberglass insulation (Spyder) with an adhesive that made it "stick" to the walls. Like lzerarc said, spray foam would have been way to expensive! When I back at my home computer tonight I can post a picture of the walls after insulation was installed, prior to drywall.

My father is a structural engineer who designs commercial/agricultural buildings on a much larger scale. He does a lot of work for university research complexes and large scale farming operations. Residential is a foreign concept to him and will tell you that anything he would draw won't be pretty and will probably look like a barn. He has his own consulting firm and had his CAD people draw up what I sketched and then made sure the mechanicals and structual components would work. Apparently I like to design spans that require a lot of steel and had to be told "no" several times! If I had to do it again, I would have looked around and found a green designer to consult with for some additional advice.

Ok, here are some pictures during the insulation process. Our insulation contractor was here multiple days. During the first step they caulked everywhere they could, spray foamed key areas that were hard to insulate otherwise, such as tight corners, spaces that were too big for caulk, but too small to effectively place the insulation, sill plates and certain attic areas. They also spray foamed any penetration in the exterior such as the dryer vent, sprayed behind all outlet boxes and any areas where we had wires going through the sill plates within the exterior wall assembly. These pictures were done at this point.

When this was all done, the insulator came back and sprayed the Spyder fiberglass to fill the wall cavities entirely.

When this step was complete, they waited until the drywall was up (for the ceilings to be in place) and came back and placed loose cellulose in all attic spaces to an R60 thickness. I didn't take any pictures of the attic at this point!

If your going to do sprayed in insulation, even if its a blown in sprayed type, you might want to consider running a piece of 2'pvc along a stud in the main tv room and computer room. I would run two 90's for the tv room for a wall mounted flat panel and for the entertainment, that way it will be a ton easier to run cables in the future, just measure how far they are from the wall if you decide to enclose, or you could always put a plate over it/then hang a picture etc if it was above your tv. Through some insulation then cap... would be a great way to run cables, or run in ceiling speakers from room to room later.

We live in NEO. We just moved into our new home two weeks ago. My husband is the technical guru for our house, but I can tell you that we have a two-story, full ICF home with windows with a U value of .3 or lower and a low E 366 UV coating. (DH just told me that) DH is from Holland and a concrete home was important to him. I live with a brain injury, and the reason we built the house was to have a QUIET universally designed home to increase the quality of our days. (My head is really pounding today, so hopefully I'm coherent).

Our house is 2900 square feet, and our January Gas AND electric bill was $109 (with the house open most of the day with subs workings) and $120 in February (with the house open for most of the month.

I can't explain all the technical things, but it was really helpful for ne to walk through different homes to see and feel the difference. We went to pretty much every model, new home open house and Parade of Homes event for four years before landing with our builder.

We couldn't be happier with our house. Check out the link below for more details (we blogged through the whole process because I have memory issues and this was part of my speech therapy to "remember").

Since you're close, if you'd like to come visit our house to see what we did and hear and feel what an ICF house sounds and feels like, you can PM me.

Good luck with your build. There are million decisions to make!

Here is a link that might be useful: de Jong Dream House

Its fun to see the evolution of a home on a quality thread here.
Lyns, sounds like you are interested in getting some free heat from your south windows and you should be. Passive Solar Design can provide 40-90% of your heating needs. You will need to completely eliminate your south facing porch roof but still have three other sides that will not block the sun and the west would be beneficial to block. Check out the link below for more.

I also have to suggest you look into SIPS for your above grade building envelope and Pre-cast concrete panels (Superior is one brand) instead of ICFs.

Here is a link that might be useful: Cost Effective Passive Solar Design

Hi All! I'm back to the forum.. with a sick husband, a 2.5 year old to care for and being 30 weeks pregnant, I haven't found time lately to reply!

Thanks, westiegirl for the additional images! That really clears up the difference between the blown in fiberglass and the spray foam.. these terms are all new to me! And, I think it's great that you documented your house project; it has certainly helped me!

That's a great idea, oceandweller! I appreciate any "heads-up's" like that!

Thanks, ICF green, for your additional info! I spent a good deal of time on your blog and love how you have also documented the entire process. We are pretty certain we are going to go with ICF in the basement; we hadn't considered the entire home! Thanks also for the offer to look your place over, we may take you up on it sometime!

I have a few more questions, of course! I've done a lot of researching on the green building adviser website and have also been researching the idea of passive solar design.

As I have mentioned before, the plan we really like has deep porches on the front and back (front=north). The porches were one aspect of the home we were really excited about before we were planning on bumping up our shell and designing for solar gain.

The plan that we like (pre-revisions) is at http://www.ultimateplans.com/Plans/151014.aspx . Can anyone give us any advice on how we could make this particular plan be designed for solar gain? Or is that too big of a questions?!?!

Also, if we do insulate our home as some have suggested (ICF in the basement, double stud frame, highly insulated roof) would it still be best to go with air to air, or would natural gas be a competitor? We really like to use the air to air, but with natural gas being so prevalent in our area, should we still keep it a consideration?

Thanks again everyone!

Hey guys,

I have another question: Could someone please explain to me the difference between ICF and putting insulation around poured concrete walls for a basement? Besides the obvious construction and material differences, what are the efficiency differences? What makes one (I presume ICF) better?

Thanks!

That plan has no windows which face east, has one window in your master bath which faces west, and has about equal north and south windows. The porch on the front, which you indicate is north, is probably the worst place to put a porch in terms of needing protection from the sun.

Have you played around with that solar calculator I linked to?

From where I'm standing, you need to prioritize your desires, in this case, which is more important, this exact floorplan or your desire to have a house that is designed to achieve maximum performance with regards to passive solar design principles.

Ideally what you want to have is minimal northern exposure, your kitchen on the east, west windows with deeper porches to shade you from the intense summer sun, and southern exposure which works in conjunction with thermal mass inside your building envelope. The placement of the thermal mass should be optimized by tools like the solar calculator which will show you how deep into your room the sun will shine on any given day of the year as a function of your window particulars and the overhang length.

The point of the above is to highlight the ground up approach to designing with passive solar principles, that is, those principles take pride of place in how the design shapes up. Next best is to search for floorplans which appeal to you but also hit some of the checkmarks needed for passive solar design.

To your question of heating methods - it's an either or type of situation as I see it, in that with a well insulated house your heating demands aren't going to be overwhelming so the marginal efficiency difference, say for the sake of argument 15%, doesn't translate into dollar consequences which will really bite your pocketbook. To get a better response to this question I think you need to explain what you want to accomplish. I'm not really sure what gas being prevalent in your area has to do with your building plans? Does that mean that it is a cheaper method than air to air? Does that mean that you don't want your house to be different from everyone else's houses? Does that mean that there is some type of HOA guideline involved?

That plan might work if the front was south and you eliminated the front porch but obviously that wont look right without some major adjustments. I would also suggest you be careful with the attached garage. Attached garages are somewhat unsafe on normal homes but on tight homes they can be even more dangerous.

Its going to be tough to design an energy efficient, passive solar home over a forum. The help of a knowledgeable designer, builder, or consultant would probably be money well spent.

Springtime, I have no clue what your talking about with attached garages being unsafe, just wondering.

Some things that have not been mentioned that are obvious and practical, go with a darker shingle if your up north, maybe like a dark charcoal grey, I would also look into turning the attic ventilation off during the winter months as heat rises, that might further insulate the home.

I think what Springtime is alluding to is carbon monoxide poisoning risk. I.E. you start your car and forget to open you garage door. So all the carbon monoxide goes into the house.

I have to admit I am not an expert on energy efficiency like so many of the commenters that have posted, but here are my two cents for what it is worth:

We just built a home with an unfinished walk out basement, total size on main level around 2000sf and basement slightly more so our total heating/cooling load is for 4000sf. We did the air to air HP, it is a 16 seer and is amazing. We also did ICF in the basement with 2x6 on main level. We considered windows and many of other comments that have been mentioned already so I won't go into that thought process.

One thing that I haven't seen mentioned are the radient barriers for roof decking. We used LP techshield radient barrier. It has a guarantee to pay for itself within one year. The lumber company we used actually paid the differece for one of the large builders in our area to build 2 homes with the same floorplan and one with the radient barrier and one without. The lumber salesman said they measured the tempurature and there was a 30 degree difference in the houses once they were closed in.

Also we had several subs comment about the differences they witnessed working on rough in between houses with it and without it.

We just moved in a few months ago so we haven't been able to track our actual costs really yet (not to mention the 3 year old that leaves the door open ALL the time...)So far our utility bill is about half of what our old house was(that house was 2800sf finished)

Another thing to think about is the way the HVAC guys seal your duct work. There is a lot of loss if they are not sealed and insulated properly.

You mentioned a whole house fan, we LOVE LOVE LOVE ours and made sure to have one in this house. Worth the few hundred bucks to put it in, just make sure you seal it in the winter so you dont lose your heat through it.

We also installed the Napoleaon NZ 6000 wood burning fireplace. That thing can put out the heat! We did the blower system and installed the blower in the basement to help circulate the air. We turn our temp down and do overnight burns and the house is usually still in the 70s the next morning.

Like I said, no expert here but I hope it helps!

Radiant Barrier pay back in a year is a joke. I have one and I believe it cost $400 or so on new construction (steep roof, 2000 sqft per floor). I feel confident that it saves about $30-50 a year. Still not bad but one year is a joke unless I am wildly wrong on the cost. I think our energy rater had it worth $40 a year. There was a fairly good table somewhere that had its value by sqft, climate and whether ducts were in the attic. If ducts are not in the attic, its benefit is diminished by at least 50%. Good practice would to just not put the ductwork in the attic in the first place.

Lyns, I've resisted posting on this one so far, as others already have covered the basic advice. Yes, go for superinsulation, make it as tight as it possibly can be, and install the HRV for controllable mechanical ventilation. Ignore any advice to the effect that you don't want to make it too tight, because "the house has to breathe." Spend extra as required for really good windows. They do make a real difference; your energy model for the house will show you that.

Forget the whole house fan. It has little use in the sort of house you want to build. Running a whole house fan in hot weather will just draw hot, humid air through the house and make it hot and humid inside. In an ordinary house, there can be times when a whole house fan can bring in cool night air and provide almost free air conditioning. The tight, highly insulated you want to build simply will not gain heat very fast in summer, just as it won't lose heat fast in winter. Your A/C load for summer conditions probably can be met with one ton of capacity, and it won't needed very often at that.

Given that you want the house to be very tight, and will have mechanical ventilation always running (at least on low speed), that means less worry about having an attached garage, not more, provided you detail properly your air barrier at the wall between garage and house. The garage absolutely must be outside the house's air barrier. With ordinary construction, and little attention to tightness of the shell, an attached garage would be more of a problem.

I am speaking from experience here. I designed the shell of my own house and was on site for the build, advising the crew of particular things I needed to have done at certain times, some of which I just did myself. The structure is a double wall with 12" cavity filled with dense packed cellulose (R40). The attic floor is R60. Basement walls are R20 where there is concrete and R40 where framed (walkout areas). Sub-slab is R20. Windows are triple pane, around U=0.17, and all casements except for some fixed glass units. Not every window need be operable.

The final blower door test came in at 0.8 ACH at 50 pascals depressurization. That confirmed the selection of a two-ton GSHP unit for heat and A/C. The gross footprint is 2,000 sq.ft., and there are two levels, so living space is 4,000 less walls, stairwell, and whatever isn't included in "living space." The energy model, which I did myself, shows heat loss at design minimum temperature to be about 22,000 BTU/hr. Worst case A/C load is less than half that.

There also is a small woodstove in the lower level, with a firing range of 11-28,000 BTU/hr. Last winter we actually used that to heat the whole house, burning perhaps half time, while interior finishing was going on. It has an outside air kit, so the stove doesn't depend on inside air supply. I like having a wood fire now and then.

Last summer, very little A/C was needed; the unit was loafing, coming on just once in a while, and never running in second stage. This winter has not been an especially hard one for really testing the house and heat pump. Still, there were a few nights getting down around zero for a while, and the heat pump still never went to second stage. I have been told by others that superinsulated houses often do test out better than the energy model had predicted.

Lyns, you can have the same level of performance in your new house, and the cost isn't all that much more, if everything is done at the right time during construction. I totaled up everything involving the superinsulation part of our new house, relative to "ordinary," and it came to around $20K, about the price of a new car. With the savings in heating cost, the extra cost will pay for itself in less than ten years, then pay out like a slot machine thereafter. If I blew the $20K on a car, in ten years it would be a rustbucket with no value. Where's the "payout" in that? Moreover, the house really is delightful to live in, with no drafts or cold spots, worth every penny spent to make it better than "ordinary."

Dick- great post! Great air test as well.

Dick - Sounds like you built a nice tight home. Where are you located? NH?

Yes, I'm in NH, about 30 miles north of Concord, which has a 7500 HDD heating climate.

There are so many aspects to building a tight, highly insulated new house, and so many ways to get similar results. It all needs to be thought out well in advance, everything from where the air barrier is established to how the deck attaches to the house. It all has to work together to achieve the desired end result. It's mostly a matter of insulation, moisture management, and aesthetics.

I would urge anyone contemplating building a high performance house to become thoroughly versed in building science issues and construction techniques, almost as if he were doing the work himself.

In most areas, I would expect that the HO will have a diffiult time finding a contractor who knows how to do all the little things correctly and has experience in doing it. However, with the current competitive nature of the home construction business, it shouldn't be hard to find someone who understands that the proposed house is different from anything he has built and is willing to work with the HO to get exactly what the HO wants. Don't expect the builder to know all the building science details. He probably doesn't, and that's why I urge the prospective HO to become well versed on the subject, so he can specify ahead of time what he wants in the way of building science detail and later be able to work with the builder. The builder will (or ought to) respect the HO who knows his stuff and who defers to the builder on routine framing issues that have no bearing on the thermal integrity of the external shell.

Ah, we could go on and on about all of this. I've said enough.

Dick - We are also building a very tight house, but we are in NC so we have an ERV rather than an HRV. We should be moving in later on this month.