Open-Cell Spray Foam for Window Installation
This coming Tuesday, my window installers are scheduled to start. We are using thermally broken aluminum windows. We have covered the walls with Delta Vent SA. I have seen, in the Delta product manuals, the placement of a backer rod from the inside and the sealing it with one of their products (Delta Thaan?)
I asked one of the installers (they work for the Fleetwood window company) and he mentioned that they typically do not use a backer rod but instead spray open cell foam into the space between the window frame and rough opening. I am a little concerned about this: won’t the open cell absorb water? and how can you avoid filling the space where the water is supposed to drain?
Please advise on your thoughts regarding this situation. Thank you.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part