A small development in Massachusetts shows that even builders in a state with one of the most advanced energy codes in the nation are still stuck in yesterday's framing systems—the 'we've always done it this way' system.
If you are a builder and you see this on one of your job sites, it should look like your money going out the window. A missed savings opportunity. If you picked this framing sub because the price was 25% lower than the guy who knows what advanced framing is, then you broke even financially and your customers got short-changed.
Why does this matter?
Big chunks of wood in a wall mean that there will be big areas of wall surface that are cold (in winter). Because the interior humidity will be a lot higher inside a house than outside, these cold spots are places for moisture to condense, like it does on cold windows. If the section of wall is behind a couch, the mold won't be seen when it grows here.
Cold spots turn into MOLD spots
If it is a corner, as it is in the foreground, and next to the far window, the whole corner will be a cold spot. If there are any leaks in the wall, such as through an electrical outlet on either the exterior wall or the intersecting interior wall, moisture in the form of humidity will be sucked into the wall cavities where it can condense on the inside surfaces of the walls. HIDDEN mold is even worse than mold that is simply hiding behind the couch.
Framing like this also wastes energy, which wastes money and is a threat to National Security (at least is was before we got so fracking good at extracting natural gas).
To build a better wall, space the suds at 24 inches o.c. rather than 16 inches o.c.—there will be (roughly) 30% fewer studs (five studs for an 8-foot section of wall rather than seven studs).
Also, rethink the backing for intersecting walls, aka wall bucks. The wall bucks in this house are full-height studs. Odds are that the framing crew did NOT insulate the empty cavity behind the stud, so we are looking at cold spots in the wall. If a romex runs through the exterior wall and into the interior wall (hint: it will) then the cold spot has a direct path to the inner parts of the house.
Headers are not needed in the non-load-nearing gable wall at the far end of the picture. The headers are double 2x10s, with an air space between them. In theory, the insulators will stuff insulation in the space. A better way would be to sandwich a chunk of rigid foam between the 2x10s, which would provide nailing on both inside and outside surfaces and eliminate a big cold spot in the wall.
From Building Science Corp.:
Building America Special Research Project—Deployment of Advanced Framing at the Community Scale
Common Advanced Framing Details
Advanced Framing-- an edited version of an ASHRAE Journal article.
From Home Innovation Research Labs:
Advanced Framing: An Examination of its Practical Use in Residential Construction
System Evaluations & Specifications: Advanced Header Framing Design for High-R Wall Systems
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