Injecting Wall Foam and Condensation
thetinkerer
| Posted in Energy, Heating & Insulation on
I am considering having the exterior walls of my home injected with wall foam.
I live in the Dallas Texas area.
Should I at all be concerned about condensation forming and causing damage, mold, or the like?
Replies
The issue
I would ponder is how the foam will alter the drying characteristics of the wall. If there is now condensation (such as on the back of the drywall when the interior is air-conditioned, and the exterior is hot and humid), the addition of an open-cell foam won't stop the vapor movement to the cold surface (although it will slow it), but it will cause the moisture to stay there longer because it will slow the drying--it will both act as a vapor retarder and also reduce air flow within the walls.
Walls with no insulation or loose-fitting fiberglass usually have enough air movement through them to make them fairly forgiving of moisture. Foam, not so much. Cellulose might be a better choice, although it's not a slam dunk either.
It's always the unintended consequences....