sealed soffits near fan exhaust

Comment

Comment by Adin Maynard on July 30, 2011 at 4:47am

Bryce, thanks for the comment. Yes the flat was fully airsealed and brought up to R-60 with cellulose.  Each standard chute vent was improved, as can be seen in far left bay in image above. The few soffits near the bath fan were sealed to prevent exhaust air from bring brought back into the attic.  THere was plenty of 'low/high' ventilation, so this approach was taken. 
This past winter was crazy for ice damming. As a result, for attic retrofits, we are careful to improve and maintain soffit vents whenever possible.

Comment by Bryce Cramer on July 29, 2011 at 10:52am

Not sure if I understand how sealing the flow of air through the soffit will reduce ice damns. The better approach would be to stop the heat loss through the attic floor with a better insulation job. Then provide proper ventilation so that the roof deck remains cold and does not therefore melt snow that refreezes over a cold soffit. If the bathroom vent is just vented into the soffit area, I would think this would cause additional issues. The warm air (moist) air will hang inside the soffit area since the soffit is now sealed from the rest of the atiic....this should lead to moisture, mold and other problems in the roof deck above this soffit area.