如何空气将阁楼底板密封在墙上护套？
John Ranson|发布了绿色建筑技术在
I’m designing a house that will be built near Rochester, NY in zone 5. My primary air barrier will the plywood attic floor and plywood wall sheathing. What’s the best way to seal these together? For structural reasons, I would prefer if the sheathing were continuous between the first floor and attic.
Cheers,
John
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Replies
John,
There are lots of ways to do what you propose. One method was described by Carl Seville in one of his recent blogs,Topping Out.
It's far more common to use the ceiling drywall as the air barrier than the attic floor. For details on connecting a drywall ceiling air barrier with a wall sheathing air barrier, seeA Practical Air-Sealing Sequence. An illustration from that article is reproduced below.
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If you're framing the roof with regular lumber (instead of trusses), then the process couldn't be simpler. Frame the ceiling joists, lay down the plywood deck (just like building a floor!), seal all the seams in the plywood on the flat AND at the corner (plywood joist deck to plywood wall sheathing). Use a high quality air-sealing tape (Siga, 3M, Pro-Clima, Zip) or a joint/seam filler (Prosoco or Duralink). Then, install your ridge beam and rafters...business as usual.
然后，您可以运行所有照明，接线（均匀的管道和导管！），您想要在天花板托梁中......在空中障碍下面，在绝缘体下面。在我咨询的一所房子里，我们使用了用于天花板托梁的开放网桁架，以适应顶层所需的相对广泛的加热/冷却管道。
请参阅附件详情 - 一个用于空中屏障分级，一个用于这种结构的典型绝缘细节。
Here's a beautiful photo example from Daniel Ernst at Promethean Homes just prior to the attic insulation going in -http://www.prometheanhomes.com/uploads/1/4/8/4/14843776/4123868_orig.jpg
John,
Your detail will work, but I prefer a detail that raises the rafter tails so that the full depth of the attic floor insulation extends all the way to the attic perimeter.
Your detail shows that the top of the insulation is beveled at an angle. To make up for this reduced insulation thickness, you've provided some extra insulation in the 2x8 ceiling joists -- a solution that works, but which (for me anyway) is a little inelegant and unsatisfying.
I don't think there's an "ideal" solution either way, Martin. To get full depth attic insulation (20") at the eave in my detail, it seems to me you'd either have to switch to a trussed rafter with a built-up heel, or frame the heel on site if using a dimensional lumber rafter. Issues of eave overhang depth, window head height and aesthetics certainly also come into play. My detail might result in too much shading of the windows if there's a desire for a relatively deep overhang.
尽管如此，您将空中障碍细节仍然相同，并且在我看来，就像你能得到的那样直接。
In the house I am almost done building, I put 2x6 joists on top of my walls, sheeted it with OSB, covered with plastic, then used energy heel trusses right above the 2x6 joists. Then I screwed the 2x6's to the trusses from below with 7 1/2 inch screws. The 2x6 chase was used for wiring and HRV ducting, etc. Blown cellulose in the attic.