With hurricane gustav, we are getting a new roof put on our house. A roofer came by to give us an estimate. We are going with the 30 year architectural shingles. The roofer said that he would have to use the 20 year shingles on the ridge cap, and along the hips of the roof. Is this the norm when putting on this type of roof?
Using three-tab 20-year shingles is common practice, since the dimensional shingle cannot be cut well to make overlay pieces for ridge and hip caps. The three-tabs are cut into three pieces - each 1 foot long. This is commonly what is used as caps for a three-tab roof install and it "can" be used as caps on any style roof.
However, all styles of dimensional shingles also have pre-cut cap pieces available in any color choice. These cap pieces will carry the same 30 year rating as your dimensional shingles. These cap pieces will out-perform the cuts made from three-tabs. Most home stores do not carry these, maybe your roofer should get his materials from a roofing supply outlet.
I was researching new roof too, and came across the same question concerning 3-tabs. Was advised that the warranty may be more limited if using 20yr 3-tabs with 30yr AD shingle, especially in Houston with the heat. There are options like Z-ridge and Timbertex which give a much more "expensive" and dimensional look - but cost more too.
