[CyberDildonics]

Why would water be able to get through your roof but air not be able to get to it at the same time?

Why would water be able to get through your roof with spray foam making anything worse? Water damage means you have to replace things anyway.

[lm28469]

> Why would water be able to get through your roof with spray foam making anything worse?

Because your roof _will_ fail, they all do, once it does the water will collect between the roof and the foam, because while it's not air tight there will be nowhere near enough ventilation do get rid of it

> Water damage means you have to replace things anyway.

Yes, but if your entire wooden structure rots for 5 years because you didn't detected the leak since it's hidden behind 20cm of foam you are utterly fucked.

It's well documented, feel free to google it if you don't believe me.

https://sprayfoamreclaim.com/wp-content/uploads/2022/10/PHOT...

[CyberDildonics]

Because your roof _will_ fail

You said that already but it doesn't answer any of the questions I asked. Repetition doesn't make something true. There are typically shingles, then a layer underneath, then wood sheathing like OSB. All that is for the cheapest roof.

https://diy.stackexchange.com/questions/32820/is-it-ok-for-o...

once it does the water will collect between the roof and the foam

Says who? If water is getting to the wood, why isn't air getting to it? Typical roofs last for 20-30 years.

This idea that foam is bad because seeing water soak through through the entire wood sheathing is nonsense. This is also only dealing with foam on the underside of the roof, which is also not the only place or way it can be used.

but if your entire wooden structure rots for 5 years

Now your "entire wood structure" is going to rot? If you want to know if there is moisture in your wood, go in your attic. This idea that roofs blow off without anyone noticing and huge amounts of water soak all the wood in a house and the entire thing rots without any indication is not reality.

feel free to google it if you don't believe me.

You can feel free to google it because you're the one making the claims.