Insulated header design
We’re building a small house in North Idaho (climate zone 5). 2×6 exterior walls with most headers being built of double 2x’s. Planning to insulate them with 2”EPS. The options I’m considering for this are:
1) Double up the 2x’s, nailed together and set flush to the outside, 2” EPS on interior with 1/2” air space between EPS and drywall; or
2）将EPS夹在两个2倍之间（与两侧的5英寸滞后螺钉连接在一起）之间，在最内向的2倍和干墙之间有半英寸的间隙。
Both header assemblies would have a flat 2×6 nailed to the bottom. I’m also planning to air-seal interior walls with ProClima Intello Plus vapor-variable air barrier membrane.
My question is is there a reason, (structural, moisture, performance, or otherwise) to choose one method over the other? I’m an owner/builder and not concerned with labor cost, mostly just don’t want to waste energy or grow mold in the walls. Thanks!
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Replies
A header is stronger joined together and many building inspectors in our area require they are built that way. Putting the foam to the inside helps prevent drywall cracks sometimes caused by shrinkage of the 2x lumber. Just make sure you put a plate under the header for a nailing surface.
Adam,
https://www.jlconline.com/how-to/insulation/sunsulation-headers_o
I'd add:
- The advantage of having the header flush with your interior framing is that you can use it as backing for trim and to attach supports for window coverings.
- Putting the foam to the interior is easier in terms of the sequence of construction, as the insulation can be added when the framing is complete.
- Sandwiching the foam makes for a less strong and stable header. My reading of our code doesn't allow the wood members to be separated.
That said - all three methods are regularly used without apparent problems.
我们一直分开,有趣的是different things are from one location to another
Russell,
A lot of what we take as necessary, or at least good practice, turns out to be very regional when you look at how things are done elsewhere. Some of the makes sense as adaptations to local conditions, but a lot is just habit or custom.
You could try Timberstrand LSL insulated headers.
http://mattrisinger.com/insulated-headers-using-timberstrand-lsl-engineered-lumber/
https://www.weyerhaeuser.com/woodproducts/engineered-lumber/timberstrand-lsl/timberstrand-lsl-framing-lumber/timberstrand-lsl-headers/
感谢您的答复。我最终将2倍的两倍在外部加倍，其中2英寸的EPS内部，底部有一个2x6板（钉子表面）。我认为结构性可能最重要，其次是能量。我仍然想知道组装的水分考虑因素；即，泡沫层的位置是否会改变/改变“冷凝表面”的温度和/或位置？如果您是从墙壁组件的内部（和外部）进行空气密封的话，这甚至很重要吗？