Dense-pack cellulose is actually pretty solid these days—settling isn’t the nightmare it used to be. Here’s what I’ve seen:
- If it’s installed right (dense-packed, not loose-blown), it stays put. Had it in my attic for 7 years, barely budged.
- It’s way cheaper than spray foam, and still does a good job with air sealing if you’re thorough.
- Mice seem to like tunneling through it a bit more than foam, but I just keep traps out... nature of the beast.
Honestly, if you’re on a budget and don’t mind a little extra prep, cellulose is a decent call. Just make sure whoever installs it knows their stuff.
Yeah, I’ve had pretty good luck with dense-pack cellulose too. It’s not perfect, but for the price, it’s hard to beat. I do wish it handled moisture a bit better—had a minor roof leak last winter and the stuff got a little clumpy in one spot. Still, way less hassle than I expected. The mouse thing is real though... I swear they treat it like a highway. But traps and some steel wool in the right places mostly keep them out. If you’re careful with install, it’s a solid budget choice.
Yeah, I’ve had the same issue with mice—seems like they just tunnel right through cellulose if they’re determined enough. I did a small shed with it last fall, and honestly, for the price, it’s hard to complain. Moisture’s always my worry though... had a weird musty patch after a heavy rain once. Still, beats the cost of spray foam by a mile.
I get the appeal of cellulose on cost, but honestly, if you’re thinking long-term for a guest house, I’d budget for something more robust. Mice and moisture issues can turn into bigger headaches down the line. I’ve seen folks save up front and then pay double fixing rot or pest damage. If spray foam’s too pricey, maybe look at mineral wool? It resists moisture and critters a bit better, and isn’t as bank-breaking as foam. Just my two cents from a few too many renos...
I get where you’re coming from on cellulose, but I wouldn’t write it off so quickly. If you’re careful about air sealing and use a good vapor barrier, cellulose can actually hold up pretty well—especially in a detached guest house where you can control the environment a bit more. Mice are a pain, sure, but I’ve seen them chew through mineral wool too if there’s food or warmth to be had.
Mineral wool’s solid for moisture, no argument there, but it’s not exactly cheap these days either. Plus, the embodied energy in mineral wool is higher than cellulose, which matters if you’re trying to keep things eco-friendly. I’ve done a couple backyard builds with dense-pack cellulose and haven’t had any major issues, as long as you stay on top of basic maintenance.
Honestly, every insulation has trade-offs. It’s more about how you install and maintain it than the material itself, at least in my experience.
