Question relating to staggered stud framing
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When using this type of framing, this site and others shows the gap between studs as the rolls are woven through there is always a void (air gap) and looks very inefficient. The blown cellulose looks to be the better of the two. Anyone can speak to this issue?
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Replies
Max,
I'm not sure what advice you saw on GBA that might imply otherwise, but if you have a staggered-stud wall on wide plates, some type of blown-in insulation (for example, blown-in fiberglass or dense-packed cellulose) is far preferable to trying to weave batts through the staggered studs.
I'm guessing that you are just beginning the process of choosing your wall type. I suggest that you read this article: How to Design a Wall.
Max,
DIYer here.
1. What Martin said.
2. If blown cellulose isn't a good option for you, you can certainly slide roxul comfortbatt between the studs of the inner wall to fit into the outer wall. That's going to be a lot easier with 24" o.c. and with 2x4 walls. 16" o.c. with double 2x6 framing (does anyone do that) would be difficult. It would be difficult with fiberglass batts because they don't hold their shape like Roxul. It won't be nearly as fast as installing them in an unrestricted space but as long as your framing is spaced to standard 24" o.c. reasonably well, it won't be too bad.
3. Have you looked into Larsen trusses if this wall is being built from scratch?
4. My personal non-scientific observation is that air trapped on the hot side of insulation radically short circuits its performance. You want your insulation boxed on 6 sides. Totally unscientific.
It seems like you would need to share your climate zone and energy goals (code minimum, pretty good house, etc) to get more advice.
I believe the OP is referring to something like this which is used for sound deadening in an interior wall. I could be wrong though. I am often, just ask my wife.
Greg's wife will probably disappointed, as I think he is onto that the OP was describing. Either way, whether used as insulation for heat or sound, leaving voids is a bad strategy.
If this is a 2x6 wall or partition...why not get batts for 2x6 wall (5.5" thick), then pull them apart (easy with fiberglass) to get about 3" thickness for each half. Then install one half on one side of the wall between the studs, and the other half on the other side of the wall, again between the studs. You'd have less compression at the studs, but a lot less airspace. Or as an earlier GBA article noted, compression of fiberglass isn't as detrimental as you'd think. You could put 3.5" batts on each side of the wall between studs instead of pulling apart the batts.
If this is an exterior wall, not a partition, you could make the wall thicker to fit 3.5" thick batts on each side. The extra insulation likely would be worth losing a little interior space. Reduce heat loss and increase comfort.