Originally Posted By: chaase@yahoo.com This post was automatically imported from our archived forum.
I have an house where the rafters have been covered with plywood and painted, so there’s no ventilation to the underside of the roof. I’m having the shingle roof replaced and wondered what type of venting I should put in? Also, can I leave the plywood up or is it best to remove it (this is not living space) for more ventilation?
Originally Posted By: mgault This post was automatically imported from our archived forum.
Concur,
Ridge vent almost the entire length of the main roofline (leave about 2-3 feet from the end), if the roof has accessable dormers over windows, ridge vent them also.
Originally Posted By: rsmith5 This post was automatically imported from our archived forum.
You will want to check and see what insulation is in the attic space before you vent. If there is a full floor you will need to check between it and the ceiling. Add as much as possible up to R-30. If there is no floor do the same. Also you will need to check the seal of the ceiling in closests and other hidden areas [sometimes sheetrock joints are left unfinished]. If there is no insulation and open sections of ceiling you will suck the heat out of the house so fast you will be able to see the fuel gauge move on a heating fuel tank! Oh yeah, the plywood has to go.
Originally Posted By: dvalley This post was automatically imported from our archived forum.
As already stated, Ridge and soffit vents will be the ultimate.
If the ceiling is finished, you will need soffit and ridge vents. The ceiling covering must be removed in order to install baffles (above the insulation) that will carry the airflow from the soffit vents right up to the ridge vents.
If there is restricted airflow behind this ceiling, this will cause moisture build-up (humidity) which can lead to Mold. Not only that, the shingles above this area usually burn and start to curl due to insufficient ventilation on the underhalf. Your new shingles might last maybe 6-8 years with insufficient ventilation.
