I think it's helpful to remember when installing this product that there may be gaps around the entry to the attic which could also be leaking cool air (where the building materials come together and join to the attic floor), and which may not be covered by this. I viewed this as an insulation project, not just something to throw in place that's going to do everything. Next, as the seam that 'attaches' to the inside of the attic entry is fabric, you have to consider how to affix that to the wooden frame of the entryway. I used staples - and a lot of them - and in addition went around that seam with a bead of caulk, because air will seep through even with a ton of staples in place. Finally, the corners can be tricky. My entry has metal braces in the corners. I can't put staples into metal, clearly, so it was necessary to fill the voids that formed between the fabric seams and the metal braces with caulk. Even without metal braces, I think it would be difficult to have a perfect fit. Having sealed the gaps between the wood joists, filled the corner gaps where the braces are, and run a bead of caulk where the fabric meets wood, I think I've done a good job sealing the attic and would recommend this product. By itself, for 100 bucks, I think it's pretty ok, but go the extra step of sealing everything tight.