Rodents Love Mineral Wool
jackofalltrades777
| Posted in Energy Efficiency and Durability on
Regarding Roxul/Mineral Wool insulation. In my experience of using this stuff. Rodents LOVE this insulation. As I discovered yesterday, I have found numerous rodent nests inside of Mineral Wool. So for the claims that rodents don’t like this stuff, that’s not true. They will build a nest and burrow into mineral wool, just like they do with other batt type of materials.
I like using it, a better material than fiberglass, but it’s not “rodent proof”.
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Replies
jackofalltrades777,
That has been my experience too.
I haven't found a lot of difference, either, and I certainly don't consider mineral wool to be "rodent proof". What I usually do is take precautions to air seal as I reinsulate though, so that's how I get additional critter protection. If I see larger gaps that a mouse could sneak through (we have a lot of mice here), I press some 1/4" mesh hardware cloth into the gap and then fill the gap with canned foam. The hardware cloth gets embedded into the foam that way, and forms a barrier that the mice can't chew through. I like to cut the hardware cloth so to that the edges all have pointy wires sticking out to help it grab onto the sides of the gap when I do this. Works great.
Bill
I was half expecting to see some false claims about Rockwool's rodent resistance, however, I was impressed by their candor:
(excerpt from Rockwool site)
"There is no test method to determine whether or not any product is rodent resistant. ROCKWOOL’s reputation as a rodent-resistant insulation is mainly based on word of mouth and lack of negative feedback from numerous customers who use our products in “cottage country”. That being said, if a certain pest type is a nuisance to your particular area, best practice is to protect the insulation."
I'm with Bill on the mesh/foam approach.
Exactly. Rodents will burrow and nest in the mineral wool. Best practice is to keep them out of it using mesh or some type of barrier they cannot get past.
Has anyone ever ordered Mineral Wool from the online company:
https://insulation4us.com/products/owens-corning-r15-thermafiber-fire-and-sound-guard-plus-all-sizes
Pricing seems decent with a delivery fee of $80
I am contemplating using the mineral wool below my SIP ceiling. The ceiling is R-40 but if I furr down the ceiling and add the 3.5" mineral wool, it will bump it to R-55. I can do the labor myself but wondering if it is worth the cost to go from R-40 to R-55 in a Zone 4B climate?
Pricing for a 3.5" x 23" x 47" bag (8 batts per bag) is about $98 per bag. You get 60 square feet of coverage per bag and 16 bags will net me 960 square feet. I will need around 1,900 square feet of mineral wool. So the total will be around $3,100 for the ceiling coverage (32 bags).
It's clearly not a rodent barrier, but I think it's a little better than fiberglass since it's denser. Yes, they can burrow into it but it takes some effort. The reduced air flow also makes it less inviting as mice and rats don't just randomly chew holes in solid material but will widen existing holes if there is air coming through.
I look at it like the difference being fiberglass is inviting to rodents and mineral wool is neutral to less inviting.