I have a house that I built 30 years ago roofing with 30yr. asphalt (not fiberglass) 3 tab shingls.
I was planning on doing a layover using 30yr. architectual fiberglass shingles.
My problem is that the old shingles are .05″ thicker than the new. This would leave an unsupported area 2.12″ by the length of the shingle (.05″ tapering to 0″) using normal layover procedures.
I assume this means I should not do a layover, but will need to do a tearoff instead.
Is this right?
Replies
It's a roof, probably one of the most important systems of your structure. Do it right.
Tear it off, check that there were no unseen problems, and put on a roof that will last 50 years.
It's stupid to put a new, high quality roof over a 30-year-old roof. Tear it off.
My problem is that the old shingles are .05" thicker than the new. This would leave an unsupported area 2.12" by the length of the shingle (.05" tapering to 0") using normal layover procedures.
You're overthinking the situation. Dimensionals are overlayed over 3 tabs (organic & fiberglass) all the time. But, IMHO, it's best to tear off.