Roofing/cedar shake roofs over ice and water
QUESTION: my wife and I built a chalet back in 1989 and did the cedar shake roof
ourselves. Its a 15 pitch..pretty steep! I'm thinking of taring off the
old shakes (it's been 26 years!) they have green and red moss on them
and are curling, but no leaks! I know shakes are supposed to have
good air venting underneath them, But to protect my home from rains I'm thinking of covering the entire roof with ice and water after my boys and I strip off the old shakes. That way the house is still protected from rains. I'm still thinking of using 30 lb.felt also and I'm thinking of dipping each shake into a larger barrel of treating solution. I know it may seem a little extreme but I'm thinking it will give us another five years of shake life. If the shakes are treated on the underside of them they may not need as much ventilation, correct? Also could you suggest a dipping solution? We'd like to get started on treating them and know its going to take time to do it, especially for drying them. Yes we know treated shakes are on the market but we're unsure of how good of a treatment job the manufacture does.
ANSWER: I am sorry this took so long, I was out of town
From my experience installing wood shakes over solid sheathing is not a good choice.
Moisture is trapped between the felt and wood shakes,Due to not being able to dry out from bottom. they tend to curl more easily.
the shakes also seam to collect more moss faster, and they loose around 5 to 10 life.
This is in California San Francisco area.. You may want to talk to a local roofing company in your...before starting this project.
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QUESTION: thanks for the info, but I'm also wondering if it will have the same effect
if I use breather felt? Its made out of plastic and its about 5/8" thick.It
doesn't get crushed.Its put on after the Grace ice and water but under the starter
and regular shakes. The 30 lb. felt goes on like normal on every row of shakes.
I think it may help, But I would think ( some air flow ) still not a lot of air flow to dry out.
as needed in your climate.The other question I would ask myself will any moisture ( condensation) get trapped in the plastic breather and freeze Then expand ??????