Not long ago someone even told me that in florida roofing companies won t let their workers go up on roofs with open cell spray foam because the roofs are so spongy the guys fall right through.
Open cell insulation problems.
It has a relatively high vapor permeance 3 perms at a thickness of 6 allowing water vapor to migrate to the roof decking at night and back into the attic air in the daytime.
Open cell spray foam insulation doesn t store the moisture.
It s the wood decking that stores the moisture though.
Many homeowners love spray foam insulation and it s easy to understand why.
Compared to traditional insulation whether fiberglass or cellulose spray foam has the potential to provide better performance via its air sealing properties high r values per inch of thickness and in the case of closed cell spray foam ability to repel moisture.
Contributing editor michael maines takes a detailed look at closed cell spray foam which is growing in popularity as an insulation material.
Both low density open cell and medium density closed cell spray foam can be used in an unvented attic to provide the needed thermal resistance and airtightness.
Maines identifies its advantages a high r value per inch a capacity for air sealing and for blocking water vapor movement and its enhancement of the framing to sheathing connection.
Both icynene open cell and closed cell spray insulation are effective insulators with both working as barriers for air leakage.
For example icynene open cell spray foam must be installed at 3 inches before an air barrier is created.
It rots roofs people have told me.
It s just a pathway.
The role of open cell spray foam.
The spray foam insulation chemicals weren t mixed properly.
Murmurs and hearsay about open cell spray foam insulation have been gaining traction for a while.
There are even fewer issues with pest infestation in this insulation product compared to the other options that are available on the market today.
The evaluation service report esr for spray foam insulation products provides a valuable resource based on a third party review of testing information useful for utilizing these.
Be sure to have that discussion with your licensed contractor and don t be afraid to double check the information before the project begins.
When it comes to insulating a home whether that s a roof insulation or floor insulation it is ideal to use icynene open cell spray foam.
Oh and when you put it in your attic spray foam.