I'm facing a tough decision regarding insulation in my attic. I recently discovered that my house gets ridiculously hot because there's only about an inch of fiberglass insulation from when it was built. I'm considering two options: the first is to spend $4-5k to remove the old insulation and install 13 inches of new fiberglass insulation while fully sealing the attic. The second option is to just blow in cellulose insulation over the existing fiberglass for around $1.2k. I understand either choice will improve my situation, especially living in Southern California where we constantly run the AC. However, I'm curious about how much of a difference blowing in cellulose would make compared to replacing everything. Is the higher cost justified? Any insights would be greatly appreciated!
3 Answers
If there are a lot of air leaks, definitely get them sealed first. However, if your old insulation is still in decent shape, adding more on top can be very effective. Just make sure nothing’s overly compacted; that could affect performance. Good luck with your decision!
If your old insulation isn’t damp or moldy, it’s usually fine to leave it in place and just add more on top. It doesn't really have an expiration date. This can save you some serious cash without compromising on comfort!
Totally! Sounds like the way to go, and that’ll help me save some cash for other home projects.
It's important to first seal any air leaks before adding insulation, so definitely make sure that’s part of your plan. I've seen people do similar work, and it's common to add a few inches of foam as a gap filler before blowing in more insulation. I've got experience in a colder state, so you might see less temperature swing down in SoCal, but still, better insulation is always a good call!
I hear you! The air sealing is a big deal, but I’d check with both companies about what's included in their quotes. I got quoted $1k separately for air sealing, so I'm surprised it's included elsewhere.
Thanks for the tips! My attic fan is broken too, so sealing is definitely a priority.