Budget planning guide

Flat Roof Installation cost in Seattle, WA

A transparent starter-scope range for homeowners planning flat roof installation in Seattle, WA. Review the assumptions, then use the project estimator for your own scope.

Starter-scope range

$15,080–$21,290

Planning midpoint: $17,740

The planning model applies a higher regional cost factor for this market.

What the model includes

Starter scope and assumptions

Adjust quantities for your project

EPDM / TPO Membrane

1,200 sq ft × $7.15

$8,580

Insulation Board

1,200 sq ft × $3.64

$4,370

Flashing & Edge Detail

80 linear ft × $15.6

$1,250

Labor (full install)

32 hr × $110.5

$3,540

This is a budgeting example based on a defined starter scope, not a quote or a live survey of local bids. Actual pricing depends on measurements, site conditions, material choices, permits, contractor availability, and the final scope.

Local guides

Compare starter scopes by city

New York, NYLos Angeles, CAChicago, ILHouston, TXPhoenix, AZPhiladelphia, PASan Antonio, TXSan Diego, CA

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