I'm about to have my house re-shingled. There's 2 layers now, so having them torn off and starting new. I don't know yet the condition of the sheathing. The house is in Central NJ (Monmouth County). (See images at end of post).
The problem is that there is insufficient attic ventilation. It's a small house (approx. 1000 SF) built in the 1930's, with very little attic space. There are 3 small gable vents (maybe 12" x 8") and not much space to add larger ones. There is one vent on each side of the house, and a smaller one on the front dormer. There's is a non-working attic fan that I'm guessing burned out due to insufficient in-take ventilation. There are no soffits on the house, as the eaves are open with exposed rafters.
I can see inside the attic through the access hatch for the fan (attic is maybe 2 ft high at highest point) and there is very little insulation. Also, the available attic space does not appear to be connected. By that I mean when looking into the attic fan hatch, I can see the gable vent on the chimney side of the roof (see attached photos), but not the vent on the opposite side. That section of the "attic" is blocked off. I also cannot see to the front gable vent, so that too may be blocked.
I'm considering having a cold roof installed as it seems I can then be sure the entire underside of the roof is properly ventilated. Does this make sense in my situation? I've also seen what appears to be 2 schools of thought:
- Attach rigid foam insulation to the old sheathing, then frame on top with 2x4's to which the new roof sheathing (and shingles) are attached.
- Add a 2nd layer of roof sheathing using 1 x 2's installing new shingles to it. No rigid insulation used.
Does anyone have experience with this? Any suggestions or information would really be appreciated!!