Integrate Shingles on New Porch Roof
with Existing Shingles on Home

by Margaret
(Lotus, Ca.)

QUESTION:I am replacing a deck with a covered porch. My brother in law is in construction by trade so is helping. However he knows nothing about roofing. I have some experience in 3 tab shingles, which is what my house has. We are going off the original roof off the house and basically extending the roof, how do I weave the new shingles in with old. I believe that I would still start at the bottom and work up. It has been suggested that I work down, I don't see how. The weave and weatherization is my main concern.

ANSWER:Thanks for visiting our site; we appreciate it. You have an excellent question.

You are correct, you will want to start from the bottom edge and work up.

As with applying shingles to any roof, invert the bottom row of shingles for your starter row.

Run a line of shingles from the top (butt it against the bottom row of shingles on your home)and lay them along each edge with the tabs facing inward.

At this point your will have a starter row at the bottom and a row of shingles along each side.

Measure your roof from the bottom to the top of your porch roof plus one row (your last shingles will slide under your home's shingles). Divide that number by the length of the tabs. This gives you the number of rows of shingles you will need. If it comes out to an odd number like 7.5, adjust the spacing to make it 8 rows. You can do this by slightly overlapping each row. The idea is to evenly space the rows so as to match as closely as possible, the shingle spacing on your home's roof.

For more information regarding roofing materials please see our front porch roof construction section.

Hope this helps and happy shingling!

Dave