Insulating wall next to garage ceiling
I live in NJ and had an energy audit done last year but I found that two of my rooms still remained cold.
These are two bedrooms where half of the rooms are above a garage. The exterior walls of these two rooms have part of the walls with no sheathing (see photo one). This area is cold because the garage roof has soffit and ridge vents so there is cold air in the winter. dense pack cellulose was blown into the garage ceiling joists below these two rooms, but it is still cold near these exterior walls.
The house is a 1960 split level that has a finished attic on the third floor and as part of the energy audit they put 2 inch polyiso rigid foam board over the existing insulation for the knee wall area in the attic along with blowing in dense pack cellulose in the floor joists in
I was hoping that if I replaced the old fiberglass and then covered it with the 2 inch polyiso board and used spray foam to seal the gaps (similar to what they did in my attic knee wall in photo 3) that it would help make those rooms warmer, but I wasn’t sure if it would cause potential moisture issues. Is this OK or is there another better solution?
I have attached three photos:
1. shows the area of the wall in question when looking through the garage ceiling
2. shows the outside of the house for the area in question
3. shows attic knee wall area insulated with Dow Super Tuff-R 2 inch polyiso rigid foam board from the energy audit
thanks for your help
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Replies
Max,
Q。"I was hoping that if I replaced the old fiberglass and then covered it with the 2 inch polyiso board and used spray foam to seal the gaps (similar to what they did in my attic knee wall in photo 3) that it would help make those rooms warmer, but I wasn't sure if it would cause potential moisture issues. Is this OK?"
答：是的，您描述的计划是一个很好的计划。该墙显示出空气泄漏的迹象。（玻璃纤维棒得到黑色污渍的原因是，它们正在从渗出的空气中滤除尘埃颗粒，这些颗粒正在从房屋中泄漏到车库阁楼中。）
当您使用时，您应该注意照片中未绝缘的管道。我不知道它是供应气管还是返回空气管道，但是无论哪种情况，都需要仔细绝缘。您可能知道，在隔离管道之前，应将管道接缝密封。
.
That duct is a supply. So I should just insulate the portion of the duct shown in the picture? The rest of the ductwork runs through the floor joists above the garage and are filled with dense packed cellulose (you can see the overflow near the duct)
I can replace the old duct tape currently on the joints with polyken mastic tape
Max,
Q。“所以我应该隔离部分of the duct shown in the picture?"
A. Yes. A galvanized heating or cooling duct installed in an unconditioned space always needs duct insulation.