If you are thinking of getting Open cell spray foam in your home anytime soon an you live in a northern state you may want to check if it’s the best thing to do. Some states allow in their building codes to use open cell spray foam but remember codes are always changing and spray foam is still new.
Here is some pics from a roof repair performed on a 7 year old building and you will see how open cell spray foam contributed to the premature wear and tear on the plywood of this relatively new building.
This roof seemed to leak everytime it was cold outside like close to zero degrees. It may have had issues with the vapor moisture barrier being inside the spray foam. Some believe that the warm air of the building can come into contact with the freezing roof and condensate inside the building against the roof and rot the wood.
This plywood is only 7 years old and it is totally devolved by something .