Matching desired construction techniques with contractors who aren’t familiar with them
My wife and I plan to build a house in the Augusta, Georgia area (right in the middle of Zone 3, 100 miles away from the coast). Using many of the methods/designs/materials I read about here and other places (e.g. Fine HomeBuilding) would be ideal. BUT, most of the local builders’ techniques/experience/knowledge are nowhere near the level of performance that I am looking for. I’m looking for a prioritized list (most “bang for the buck” at the top) of the top 10 or 20 things that I need to ensure that my house design and construction includes. But they need to be readily used by contractors that are new to the material or method. Anything that needs to be installed “just right” is out. Any recommendations are appreciated, whether comments, links to webpages or publications. Thanks!
Add’l info (not in my original post): Location is in the Augusta area, house will be slab on grade.
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Replies
Eric,
I'm interested in any suggestions that GBA readers come up with.
Here's another approach: Instead of writing your specs in a way that unsophisticated contractors can understand, maybe what you really need to do is find the right contractor. For more information on this approach, see this article: "I Can’t Find a Contractor to Do That."
Martin,
Your article nailed it.
The one local builder who builds every house "Energy Star" is only doing homes in certain neighborhoods (much easier to manage six houses in one neighborhood versus six houses in six neighborhoods).
Nevertheless, I'm still interested in feedback from others to my original question.
We engaged an architect who designs efficient structures. With reasonably detailed drawings and specs, any competent builder can build what you want.
I'd focus on air sealing first. Taping all joints just takes attention to detail. Same with sealing all penetrations. Similarly, insulation isn't complicated.
As you know if you read much here, hvac design requires a good heating and cooling load analysis. Our architect used passive house planning software to determine heat loads.
Windows should be appropriate for your climate.
Don't make the house bigger than you need.
We found that a few meetings between our architect and builder were really helpful.
Stephen,
But with the exception maybe of having to put the smart membrane on the outside of your interior walls, was there anything to scare a conventional builder away from your place? No long fasteners through foam, no odd proprietary products or techniques. I think that makes a big difference.
Malcolm: That's right. Everything was pretty simple. The membrane installation wasn't complicated. Once the concept of a continuous air barrier is clear, anyone can do it. But having drawings showing precisely where the primary air barrier is was essential. Having a few details showing how to seal penetrations, with product suggestions, is also really helpful.
And I agree that avoiding atypical products and techniques is also important. That's why I think the double stud wall was a good choice.
Thank you, Stephen.
I understand contractors' fear of the unknown. When I did my house I had them build what they're used to and then added the necessary components myself. You may not be able to do that but you can get them most of the way. I'm a believer in the "REMOTE" method of insulating and I think it would be easy for you to use that method for your envelope, especially since you are in a warmer climate. A little exterior insulation (your contractors should be used to that in vinyl siding redos) and an upgrade to the water resistive barrier shouldn't be difficult. You may find that you have to do some educating re: tapes and seals for a complete air barrier and you may have to buy a couple of cases of spray foam and fill holes on weekends, but it may be doable.
After looking for a general contractor for nine months who would build our home to our specs, we gave up and decided to be our own GC. Most of the contractors we spoke with tried to convince us to do things in a way they were familiar with or wanted to charge an exorbitant premium for learning something new. Finding the right contractor isn't always possible. Lisa
It isn't just the GC. If the framers don't know basics of advanced framing, they are the barrier.
Rural GA? That is a tall order. Mild climate + low housing values generally does not make for efficient construction techniques. (Assuming you would have said Augusta if you were there)
Air sealing is always paramount. Spray foam is good for being relatively hard to mess up. Zip walls aren't a huge stretch either. The basics are not that hard. Stick to conventional framing. Design a good south facing roof for solar. Lots of south facing windows with appropriate overhang. Our designer did not focus on efficiency much - I gave him the dimensions for our South window overhangs. Minimize west facing windows (and east facing too since it really creates the same solar gain).
In the North, they work on wall construction which is fairly difficult. In the South, solar gain is much more important. And that is really easy to do.
David Pilati, Yes, I am in Augusta. Not rural (which would be a tall order), but I will still be limited in contractor options.
I know your pain as I’m dealing with this issue right now. I designed a house in rural Illinois where the county code is 2006 and newly Illinois 2015 IECC, but I don’t think it’s enforced. My client’s father is the builder, and he’s willing to go along with his son’s wishes, but I don’t think he’s too keen on learning advanced framing, outsulation, rain screens, sealing, water proofing, etc. I’ll be going to their town for the first week of framing to train them on new methods. I’m hopping all goes well and not get run out of town or decapitated.
There are some difficult issues to overcome. Since this house will be a ZERH, we’ve had a challenging time recruiting a qualified ZERH Rater. I provide detailed drawings, and yet the truss company designed all roof trusses without a raised heel, and many of the floor trusses without the duct chases lined up or chases at all, even though they had a truss layout with the chases shaded and roof truss drawings showing heel-truss. Translation, they never bother to check details or notes. Now they are redoing all trusses. A total waste of time and effort.
They don’t believe in soils test or engineered foundations. This house will be built on farmland, with a walkout basement, and the way I designed the foundation is scrapped to be replaced with “what we do here”. The owner is been formally warned.
They’re in the process of hiring an HVAC contractor. I’m keeping my fingers, eyes and toes crossed that that doesn’t become the biggest hurdle, which usually is.
The owner says that he’s scared that the cost of building this house is going to be higher because all the detailed drawings and extra work is scaring contractors. I feel I’m going back 20+ years in my profession, back in the day I started designing high-performing houses. Very Frustrating!
Eric,
In zone 3 you don't need many fancy techniques to get a good energy efficient house. I would just focus on the design details that can be built with common construction techniques.
For overall targets this is a good paper to read:
https://buildingscience.com/sites/default/files/migrate/pdf/BA-1005_High%20R-Value_Walls_Case_Study.pdf
In your case probably the easiest is to go:
-2x6 construction with high density batts (don't worry about advanced framing)
-taped sheathing for air sealing
-decent lowE windows with the right SHGC for the orientation
-get your HVAC designed (NOT by the HVAC contractor)
Getting the HVAC inside the house is probably going to be your biggest hurdle. If you have an sealed insulated crawlspace/basement, get it installed there.
Might be the easiest is to design the house with a conditioned attic instead of fighting the uphill battle of moving the HVAC.
The best resource on high performance building in your area is Southface Institute (https://www.southface.org). Although they are about 2 hours west of you, they may suggestions in terms of an approach to your home project or even able to recommend a building professional.
Peter
Thanks, Peter. I will check that out.