Residential Flat & Low-Slope Roofing Solutions
Est. 1995
Family-Owned
BBB
Accredited Business
Licensed
& Fully Insured
James Hardie
Elite Preferred Contractor
300+
5-Star Reviews
Residential Flat & Low-Slope Roofing
Why Your Garage Roof Can't Have Shingles
It is not a preference, it is the code. Washington’s residential building code sets the minimum slope for asphalt shingles at 2:12 — two units of rise for every twelve of run. Anything flatter than that cannot be shingled, and the rule is the same whether you are in Seattle, Bellevue, Everett or Tacoma.
Membranes are allowed a great deal lower, down to a quarter unit in twelve. Torch down, TPO and PVC all carry that same minimum.
So the flat parts of a house need a membrane, and around Puget Sound that usually means one of these: a flat-roofed garage, a shed or bump-out addition, a sunroom or enclosed patio, a carport, or the low-slope sections that came as standard on split-levels and mid-century homes. Roof decks over living space are the newest version of the same problem.
If a roofer offers to shingle a section like that, they are either not measuring the slope or not reading the code.
Which membrane depends on the roof. Torch down is usually the answer on smaller sections, and it repairs well in place. TPO and PVC make more sense across larger areas and where a reflective surface is worth having. We measure the slope and spec from the roof rather than defaulting to one.
Flat roofing work on a house happens directly above the rooms people live in, and low-slope assemblies involve heat or adhesives depending on the system, so ventilation, a protected work area and a fire watch where the method calls for one are set up before the work starts — and the roof is left dried in every night.
Our safety program has been recognized nationally by the NAHB, and our record with L&I is clean — no safety inspections, no license violations, no claims against our bond. You can check that yourself under contractor license SIDEPI*008N1. More on how we work safely.
How We Re-Roof a Low-Slope Section
Tear-off first, then the deck. Low-slope sections on older homes have usually been leaking quietly for a while, and the deck tells you how long.
Drainage engineered, not assumed. Flat roofs fail at ponding water, so slope-to-drain and the edge details are worked out before any membrane goes down. A section that ponds after every storm was built wrong, not worn out.
The junction is the detail that matters. Where the low-slope section meets the pitched roof above it is where most residential flat-roof leaks actually start, and it is the part a shingle crew is least likely to get right, because it is not a shingle detail.
Roofing and siding handled together. Where the low-slope area sits against siding we do both, so the wall-to-roof joint is built once rather than split between two trades who each think it belongs to the other.
System detail lives on the product pages. Torch-welded or hot-air-welded seams and flashing at every penetration are covered on the torch down and TPO and PVC pages.
Safety. It matters on a small job as much as a large one. Every crew lead is first aid and CPR certified, crews meet weekly on safety, and a superintendent checks each site daily against a written list. Debris and fasteners come off the ground every evening and ladders and access are secured overnight. Our program carries national NAHB recognition and our L&I record is clean — check it under contractor license SIDEPI*008N1. More on how we work safely.
Why Choose Side-Pro?
- We measure the slope before we quote, so you get the system the code actually allows rather than the one that is quickest to lay.
- Roofing and siding under one contractor, so the wall-to-roof joint above a garage or addition is built once by one crew.
- Drainage is corrected, not re-covered. A section that ponds gets fixed at the re-roof rather than left for the next one.
- Deck condition is shown to you at tear-off, with the repair priced from what is there rather than guessed from the ground.
What Drives the Cost on a Smaller Flat Roof
Free walk-through, real number, no pressure.
Flat & Low-Slope Roofing Questions
Can I just put shingles on my garage?
Not below a 2:12 slope. Washington's residential building code sets that as the minimum for asphalt shingles, and a garage roof is usually flatter than it looks from the ground. Below 2:12 it has to be a membrane — torch down, TPO or PVC — all of which are allowed down to a quarter unit in twelve.
How do I know what slope my roof is?
We measure it at the walk-through, and it takes a minute. If you want a rough idea first: a roof that looks flat from the street is almost always under 2:12, and so is anything you could stand on comfortably without bracing yourself.
My flat section ponds water after rain. Is that normal?
No. Ponding is where flat roofs fail. A section that holds water after every storm was built without enough fall rather than simply worn out, so it gets corrected at the re-roof rather than covered over.
Which membrane will I end up with?
It depends on the area and the access. Smaller sections usually go to torch down, larger ones to single-ply. The detail on each is on the torch down and TPO and PVC pages.
Can you do just the garage, or does the whole roof have to be done?
Just the section is fine, and it is most of the work we do around Puget Sound. The one thing worth checking is how much life is left in the pitched roof next to it. Doing both together saves a second setup and means the join between them gets built once.
Can you tie it into the pitched roof above?
Yes, and that junction is the detail that matters most. It is where most residential flat-roof leaks start, and it is the reason to have one contractor handle the low-slope section, the pitched roof and the wall between them.
What Our Customers Are Saying...
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Please fill out our FREE ESTIMATE / INSPECTION form or call today to discuss your roofing or siding project with our friendly staff.
Office: 425-486-4777
Fax: 425-483-5727
Address:
17270 Woodinville-Redmond Road NE
Suite 700
Woodinville, WA 98072
Side Pro Exteriors is a locally owned and operated siding, roofing and exterior renovation company since 1995. We provide roofing and siding replacement to over half of Washington State including King Snohomish and Pierce counties.
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