Originally Posted By: weebl
I have no clue if ridge vents are legal here. I've never noticed them anywhere before, but then they're designed not to be that noticeable, either. Would't work for that section, anyway. It is just a small slope that sticks out from the side of the house. No accessible attic there. Sort of like the roof on the right side of this picture over the garage door, but on my house, this is where the kitchen table and door to the deck is:
I do remember when I was a kid, the roofers my dad hired improved the ventilation (wasn't too bad in that house, but wasn't great either) by cutting holes to install this sort of vent.
I imagine one or two of those would solve the issue there. The problem doesn't seem to exist on the other roofs of the house.
I'll double check, but I believe ridge vents are building code in Ontario now.
Originally Posted By: Number_35
Weebl, our prairie climate sure beats up a roof, doesn't it? My asphalt shingles looked rough here after about 12 years, and we finally replaced them when they were about 15 years old. A '25-year' asphalt shingle does not last 25 years here.
Replaced them with fibreglass-based (vs. the 'organic') shingles, and what a difference! Eleven years later they are showing no signs of curling.
We also put down 'ice & water guard', a sticky membrane, in all the valleys and on the first metre or so of the edge of the roof deck, and added five vents (going from three to eight).
If I were to do it again, I'd use ice & water guard over the entire roof.
Even with the increased ventilation, we still get ice dams some winters - I think the only solution will be to insulate the underside of the deck with spray foam.
Don't kid yourself, that's everywhere. ALL the manufacturers have clued in their warranties aren't worth the paper they're written on. My shingles are supposed to be 25 year shingles. They're 12 years old, and they're basically coming up due *in Northern Ontario*.