Flat Roof Replacement Cost in Seattle
Residential flat roof replacement cost depends on the existing assembly, drainage and chosen membrane.
Porches, additions and mostly low-slope homes need their own inspection and written scope.
EPDM Rubber Roofing and Single-Ply Membrane Prices
Every roof is different. Your exact price comes after a free inspection.
Full single-ply membrane or rubber roof replacement
$1,500–$2,000 per square (100 sq ft)
Typical replacement range including tear-off and haul-away. A roofing square measures 100 sq ft of roof surface.
What Drives the Price
Area and existing layers
Measured surface area and the assembly being removed affect material and disposal work.
Membrane choice
Membrane type and thickness affect the price. Confirm the exact proposed material and assembly.
Drainage
Slope and drainage paths need an on-site assessment; a membrane alone does not resolve every drainage problem.
Decking and moisture
Insulation, roof structure and wet or damaged decking can change preparation before a new system is installed.
Edges and penetrations
Wall transitions, roof edges and penetrations need compatible flashing details.
Access and scope
Height, staging, permits where required and connections to the main roof affect the proposal.
How to Read Your Written Estimate
- Measured low-slope area and material system.
- Removal, disposal and condition of the supporting deck.
- Drainage, edge details, penetrations and transitions.
- Insulation or preparation included and any exclusions.
- Permit responsibilities and separate written warranty terms.
Comparing Estimates Fairly
Compare the same membrane assembly and drainage scope. Check whether proposals include removal and preparation or cover a different approach.
Low-slope additions should remain distinct from a pitched-roof estimate so neither their area nor their details are silently assumed.
Read about this service or See My Options for an inspection-specific estimate.
Financing Your Project
Ask about project eligibility and payment options with your written estimate. Financing is subject to credit approval, and financing options vary. Rates, terms and any minimum borrowing amount are set by the lender; an estimate is not a financing application.
Explore Monthly Payments and review the lender terms before applying.
Cost Questions
What is the flat roof replacement cost?
Typical full single-ply membrane or rubber roof replacement is $1,500–$2,000 per square (100 sq ft), including tear-off and haul-away.
Which residential low-slope materials are available?
We offer single-ply membranes and rubber roofing. TPO and PVC are the heat-welded single-ply membrane options. EPDM is the rubber roofing option. Suitability depends on the roof and proposed assembly.
Can Instant Quote price a mostly flat roof?
Mostly low-slope homes require an inspection rather than an online price. Optional low-slope additions are kept separate from main-roof pricing.
Will new roofing fix standing water?
Drainage needs assessment. Ask whether slope or drainage work is required and whether it is included; a new membrane alone is not a universal solution.
Is this guide for commercial roofs?
No. GripGo services and this guide are for residential roofing, including low-slope homes, porches and additions.
Plan Your Next Step
Instant Quote estimates roof replacements and standard gutters. Repairs, moss removal and mostly low-slope roofing need an inspection-specific estimate.