I want to build a car port off my house. Due to window placement the highest part of the roof could only be 10 feet above ground. It will extend out 16 feet. If I want the low point of the roof to be 8ft I get atan(2/16) = 7.1 degrees. I live in New Jersey, which gets a lot of rain. Is this too shallow of an angle?

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It depends on the type of roofing you’re going to use.

Its steep enough for single-ply membranes. We use single- ply membranes down to 1/4” per foot.

Make sure you have adequate (large enough) gutters and downspouts.

I live in a area that has a significant amount of rain (60” or more per year) and we have a few downpours too. I’d use a 4” gutter and 2 - 2”x 3” downspouts for your carport.

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