Roofing over the old layer is faster and cheaper on paper. It also hides the problems that matter. Here is how to tell what your roof actually needs.
What roofing-over hides
A new layer over the old one hides soft decking, bad flashing, and the leak you already have. Shingles only cover the wood, they do not fix it. The rot underneath keeps going, now sealed in the dark where it stays wet. Roofing over also adds a full layer of weight the framing was not built for, and it voids most shingle warranties the day it goes on. You paid for a new roof and the old problem is still under there.
Why roofing-over costs more later
It looks cheaper because it is faster and skips the tear-off. The savings do not last. When that second layer fails, and it fails sooner, the crew has to tear off two layers instead of one, which costs more in labor and dump fees. Any decking that rotted under the cover-up gets worse the whole time, so the repair grows. Roofing over is borrowing against your next roof at a bad rate.
When a tear-off is the answer
If the roof already has more than one layer, is leaking, or is near the end of its life, tear it off. Same if you see sagging, or the shingles are curling and dropping grit in the gutters. A tear-off is the only way anyone sees the decking, the flashing, and the rot. You cannot fix what a cover-up keeps you from looking at.
What code says here
Washington code caps a roof at two layers of shingles, so if you already have two, roofing over is off the table anyway. A reroof pulls a permit and gets inspected, and a crew skipping the permit is usually skipping more than that. We pull the permit, do it to code, and leave you the paperwork, which matters when you sell the house.
What you get from doing it right
Tear off to the deck, replace any rotten sheathing, new underlayment and ice-and-water shield, and fresh flashing in every valley and around every vent. That is a roof that beats the next wet winter, not just this one, and carries a warranty that actually holds. It costs more on day one and less over the twenty years the roof is supposed to last.
Common questions
We get on the roof before we quote it, count the layers, and check the decking at the eaves where it goes soft first. If a repair honestly buys you a few more years, that's what the quote will say.
