Dense pack Q: Can fiberglass batts be extracted without demo’ing a wall?
OK, a few more insulation questions more question, then I think I’ve hit my quota for the week (year?) I want to learn a bit more about dense packing a wall just so I have that as a data point to make my final decisions.
1) I’m wondering if faced fiberglass batting varying between 15 and 50 years old can be pulled / sucked out through a slot in a wall in order to dense pack cellulose. Most of the fiberglass is the super itchy yellow stuff that I just assume leaves the premises. I know you can dense pack on top of it, but something tells me that is not the best solution to optimize wall performance.
2) If it can’t be easily removed, and sheet rock has to be demo’d, how do you dense pack the wall after recovering? Do you just leave the top few inches open and then cover it at the end, or are holes cut how they would be with an existing wall?
3) If one wanted to use the double wall method, would the inside wall have to be a full 2×4 or would slimmer studs suffice?
4) Finally, can dense packing be used in tight attic spaces where the sloped roof meets the joist?
谢谢！
瑞安
Replies
瑞安,
If your existing stud walls are filled with fiberglass batts, it doesn't make much economic sense to try to remove the fiberglass batts and replace the fiberglass with cellulose. Instead of following your plan, simply concentrate on air sealing.
如果您真的想增加墙壁的R值 - 这项努力不太可能具有成本效益 - 然后安装内部或外部刚性泡沫层，比构建双螺柱墙更有意义。
但是，如果您绝对决心遵循您的计划，我想你可以从每个墙壁的底部去除12英寸高的干墙，房间的长度，以及12英寸高条带从每个墙壁顶部的干墙，并尝试将玻璃纤维击球击出去。这是一个愚蠢的计划，但是什么是可能的。（真的，在我尝试这个之前，我只会将一些纤维素吹入每个螺柱舱，并压缩击球。）
If you want to blow cellulose into the stud bays after your fiberglass wrestling match, you could patch the drywall at the botttoms of the walls and fill them with a hose from the top. If you really wanted to.
有时可以通过去除一条壁板和护套来获得旧的屁股，但通常不是。如果你有27个指甲点抓住蝙蝠，那就几乎是不可能的（除非你是一个真正的惩罚，除非有更多的时间而不是感觉。）
It's fine to leave the fiberglass in there and dense-pack over it. It's sometimes possible to get a dense-packing tube between the fuzzy side of an R11 and the sheathing by running air-only on the blower while inserting the tube, but there's an art to it. With R13s it's practically impossible, but you can drill multiple holes per bay and get fairly high density along with a substantial improvement in air tightness.
The performance improvement boost is primarily due to better air tightness, but with 50 year old mouse-nested R11s the raw R value is bumped up too. With R13s in good shape, reasonably installed, it's probably not worth it.