Attic ventilation - experts can't agree -
Hi - I am remodeling my attic
- the house is about 110 years old
- the roof consists of cedar shingles
- there is no attic ridge vent or sofit vents
- the shingles are nailed onto nailers that run horizontal across the rafters
- through that a good part of the shingles is openly exposed
- I am planning to put insulation up into the roof in between the rafters to make the attic a liveable space
I understand that I have to leave a space in between the insulatiuon and the cedar shingles for air circulation.
the disagreement between 2 contractors is the following:
1. I need to build in a ridge vent and sofit vent to allow complete air flow...
2. The other person says, that I can put the insulation all against the nailers (which are 3/4 inch thick), because of the nailers I have an airspace between the shingles and the insulation, also because of the nailers air can flow horizontally across the roof/in between rafters. He says that the cedar shingles breathe enough and even so their is no top level ridge vent enough air can move and leave the under the roof.
I understand that option 1 may be ideal, but obviously it is also intrusive and more expensive ...
do you have any views?