How to make GAF Ridge Cap Shingles

roofshedshingles

I have Timberline shingles but not the ridge cap ones

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How do I "make" the ridge cap shingles?
https://www.gaf.com/roofing/residential/products/ridge_cap_shingles

Since I don't have the 3-tab shingles. This is for a shed so I don't care much as long as it won't leak. Could I just cut to 1/3?

UPDATE 1
My shingle is metric so it's 39 3/8" long actually. So I am wondering if it is OK to cut it 13" for ridge edge shingle? Plus this has adhesive strip on the top (not center). I don't know if it matters (see highlight below as adhesive strip):

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UPDATE 2 (WRONG)

Illustration to use the top part only (the one with one layer). Cut to 1/3 and use the "x" pieces for ridge caps.

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Best Answer

I've done just that in a pinch, but I recommend centering your tabs on an inset section (the part along the bottom half with only one layer). This will allow much easier bending over the ridge, and your nailing will have more structure as well. You'll use more shingles, but they'll install easier.

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Cut at the red line. Fold in the center.