What flat & TPO roofing covers
Not every roof has the pitch to shed water with shingles. Flat and low-slope roofs - common on modern homes, additions, garages, porches, and most commercial buildings - rely on a continuous waterproof membrane instead. Get the system wrong and water pools, seams fail, and leaks follow. Get it right and you have decades of dependable protection.
DG Contracting handles the full range of low-slope work:
- New TPO membrane installation for homes and commercial structures
- Tear-off and re-roof of failing flat roofs - built-up (tar & gravel), EPDM rubber, or old TPO
- Flat roof repair - seam splits, punctures, ponding, flashing failures, and parapet leaks
- Commercial flat roofing for warehouses, storefronts, offices, and multi-unit buildings
Founded in 2013 and family owned (the "DG" is for founder Dorothy Gail), we bring the same standards to a single porch roof as we do to a commercial building.
What TPO is - and why it works here
TPO (thermoplastic polyolefin) is a single-ply roofing membrane that has become the leading choice for low-slope roofs. It is welded together at the seams with hot air, creating one continuous waterproof surface with no adhesives or tar joints to break down over time.
For the Inland Northwest specifically, TPO has real advantages:
- Reflective white surface bounces summer heat off the building, cutting cooling costs during our hot, dry Spokane summers
- Heat-welded seams stay sealed through years of freeze-thaw cycles that pry apart lesser membranes
- Flexible and durable - handles heavy snow load and the expansion and contraction our wild temperature swings demand
- Resists ponding water, UV, and chemical exposure better than older built-up systems
Your options for low-slope roofing
TPO is our most-recommended membrane, but the right system depends on your building, budget, and how the roof is used.
TPO single-ply
The all-around best value for most low-slope homes and commercial buildings: energy efficient, long-lasting, and clean to install.
Modified bitumen & built-up
A heavier multi-layer system that still has a place on certain commercial roofs and high-traffic areas.
Tapered insulation
On roofs that pond water, we can build in a tapered insulation slope underneath the membrane so water drains instead of sitting - one of the most common fixes for a problem flat roof.
Not sure which fits? That is exactly what a free estimate is for. We will assess your roof and recommend the system that actually makes sense for it.
How DG does the job
Flat roofs are unforgiving - the details are where most installers fail. Our process is built to get those details right:
- Free inspection & estimate. We measure the roof, check the slope and drainage, evaluate the existing system, and give you a clear written quote with no pressure.
- Tear-off or recover. We remove failing layers and inspect the deck for rot or soft spots, replacing what needs it before anything new goes down.
- Insulation & membrane. We lay insulation (and tapered slope where needed), then install and heat-weld the TPO membrane into one watertight surface.
- Flashing & terminations. Every penetration, parapet, drain, and edge gets properly flashed - this is where roofs leak, so this is where we slow down.
- Cleanup & walkthrough. We leave the site clean and walk the finished roof with you.
Why GAF Master Elite & a 15-year warranty matter
DG Contracting is a GAF Master Elite contractor - a status held by only the top 2-3% of roofers in the country. It is not something you buy; it requires proven workmanship, full licensing and insurance, and ongoing training. On a flat roof, where a single bad seam can mean a hidden leak, that credential is your assurance the job is done by people who know membrane systems cold.
Every full replacement is backed by our 15-year workmanship warranty plus available GAF material warranties through our warranty programs. We are licensed and insured in both Washington and Idaho, and we have earned a 5.0-star rating across 288 Google reviews doing exactly this kind of work.
Built for the Inland Northwest climate
A flat roof in Spokane or North Idaho takes a beating most regions never see. Heavy winter snow sits on it for weeks. Freeze-thaw cycles work at every seam. Ice dams back water up under edges. Then summer flips to hot, dry, UV-intense days that bake the membrane.
We install for those conditions - proper slope to drain meltwater, heat-welded seams that survive the freeze-thaw, and flashing details that hold up to ice and wind. It is the same reason customers come to us for roof repair and replacement across the region: we build for the weather we actually have, not the weather in the brochure.
