Wood shingles must be installed on slopes of not less than what ratio?

Wood shingles must be installed on slopes of not less than a 3:12 ratio to ensure proper drainage and minimize the risk of water infiltration. This slope is critical because shingles need a certain angle to shed water effectively. A 3:12 slope means that for every 12 horizontal inches, the roof rises 3 inches. This is the minimum angle that allows gravity to assist in water runoff, reducing the likelihood of moisture accumulation under the shingles, which can lead to rot and other structural issues.

Given this context, a slope steeper than 3:12 would enhance performance further, but installations at a lower slope would compromise the efficacy of the wood shingles, thus heightening the risk of premature failure.