Homeowners researching roofing tend to focus on the shingle. Roofers pricing the job are mostly thinking about everything else.
Area and pitch
Roofing is measured in squares — one square covers one hundred square feet — and your roof is considerably larger than your floor plan suggests. A steep pitch adds more still, because it increases surface area and because it changes how the crew works.
Above a certain steepness, work requires staging, harnesses and slower movement. The same square footage takes materially longer, and labour is the larger part of most roofing quotes.
Layers to remove
Tear-off and disposal of one existing layer is a known quantity. Two or three layers is proportionally more work and more disposal weight, and disposal is charged by weight.
This is a common source of quote variation. A roofer who has been into the attic or lifted an edge knows how many layers are up there. One who has estimated from the driveway may not.
Decking condition
The single largest source of change orders in Washington roofing. Nobody knows the state of the decking until the old roof is off, and in Western Washington’s older housing, finding rot is common rather than exceptional.
What separates a good quote from a poor one is not whether it predicts the amount of rot — nobody can — but whether it states a per-sheet or per-board rate for replacement. With a rate agreed upfront, a discovery becomes arithmetic. Without one, it becomes a negotiation while your roof is open, which is the worst possible position to negotiate from.
Penetrations and complexity
Every chimney, skylight, vent, dormer and valley needs flashing, and flashing is skilled, slow work where leaks originate. A simple gable roof costs meaningfully less per square than a cut-up roof of identical area.
This is why comparing a neighbour’s price to yours rarely works even on similar houses. Complexity is not visible in square footage.
Material, and why it matters less than expected
Material is a real input but a smaller share of the total than most homeowners assume, because labour, tear-off and disposal do not change much between asphalt grades.
Stepping up within asphalt — to an algae-resistant grade, worth specifying in Western Washington — is usually a modest increase. Stepping across to metal is a different order of decision, with a much higher upfront cost and a much longer service life.
Permits and disposal
Both vary by jurisdiction. The practical question is whether they sit in the quote or land on you separately, and it is worth asking explicitly rather than discovering later.
Season
Washington roofing compresses into the dry months, which means every roofer is busiest at the same time. Booking outside that window generally means better availability and a less rushed crew. If your roof is not actively leaking, getting quotes in late winter for early-season work is a genuine advantage.
Making quotes comparable
Ask every roofer to break it down identically: squares, layers to tear off, material and grade, decking allowance with a stated rate, flashing and vent work, permit responsibility, disposal, cleanup, and the warranty split between material and workmanship.
Three quotes structured differently describe three different jobs, and the cheapest is usually the one that excluded something.