Anyone know how spray insulation with polyurethane insulation works.

[Rättochfel]

Considering converting a non-insulated garage built with stone walls and a wooden roof structure with sheet metal into a living space!
And a non-insulated concrete slab!
How does it work if you spray insulate the walls and roof with polyurethane insulation? Does it also work for the floor?
What happens with the wood that's covered with foam? Won't there still be condensation and mold later on? Then, practically, how is it sealed/gypsum boarded afterward? It's quite knobby. Is it just nailed over with OSB and gypsum, or is it filled in two rounds? It looks very quick and smooth but really troublesome if it goes wrong! If you don't like sanding 😝 Anyone with experience in this, used it? How thick a layer do you need for residential standards?

 

[Dan_Johansson]

Stone walls? What kind of stone?

Can't see what advantages spray insulation would have over regular insulation, it's just a matter of framing up as thick as you have space for and insulating...

 

[jonaserik]

polyuretanisolering

Is another kind than the one from the 70s, like ischaskum (I hope I spelled it right) and a lot of holes were drilled into the panel and the joist, sprayed in and it became like a styrofoam board but more porous. It disappeared later, I believe it somewhat changed and settled, so there were large air bubbles everywhere. Otherwise, maybe not wrong, but I have no experience with it.

 

[Rättochfel]

It's a different type than the one in the 70s that was ischaskum (hope I spelled that right) and had lots of holes drilled into the panel and joists, sprayed in and it became like a styrofoam board but more porous. It disappeared later, I believe it somewhat changed and collapsed, creating large air bubbles everywhere. Otherwise, maybe not wrong but I have no experience with it.

Yes, it was a different variant! I think I've actually seen that variant once! It was loose styrofoam balls and these could "flow" away over time! I imagine it would be difficult to clean up, styrofoam/plastic everywhere afterwards! No, this becomes more like a sticky mess and adheres to everything! Either sand it off or remove what it's attached to! Maybe even worse to clean up when it turns out to contain something carcinogenic😀

 

[useless]

What was common in the 70s-80s was called carbamide foam. It is a liquid-based foam that is injected into cavities, so there are no pellets from it. The disadvantage (apart from that it emits formaldehyde) is that it quite quickly became brittle and more or less falls apart on its own.

 

[jonaserik]

It wasn't bullets but rather a paste that was injected and hardened. It was a very popular measure back then but disappeared. I don't believe the part about being carcinogenic, but it becomes gooey and where it's not supposed to be, it's very difficult to remove, as far as I know, it resembles a bit of sealant foam but doesn't expand much. Otherwise, that method has been used for insulation; it seeps into all holes (even where it's not supposed to be) and seals tightly.

 

[useless]

I don't believe in the carcinogenic part

Yes, formaldehyde is indeed highly carcinogenic. However, one might not need to be so worried about insulation that is 40 years old and has already emitted most of the volatile formaldehyde.