You’ve patched the flat roof over your addition three times, and it still leaks every spring. Or water sits on the roof over your garage for days after the snow melts. When you start looking into flat roof installation in Denver, the hard part isn’t finding someone to sell you a new roof. It’s knowing the new one will actually fix the problem and not just repeat it.
That’s a fair thing to want. A new flat roof should drain properly and stop the leaks for good.
APC Roofing installs flat and low-slope roofs on Denver homes and small commercial buildings, from a back porch to a full low-slope roof. We’re GAF Certified, licensed and insured, and inspections and estimates are free. Call 720-902-6940 and a roofer will come up and take a close look at what you have.
Signs it’s time for a new flat roof
Not every leaking flat roof needs replacing. A new roof makes sense when you see some of these:
- The membrane is cracked, brittle or shrinking away from the edges across most of the roof
- Water ponds in the same spots for two days or more after rain or snowmelt
- The insulation under the roof is wet, which shows up as soft or spongy spots underfoot
- You’ve had several repairs and new leaks keep showing up
- Hail has bruised or punctured the membrane in many places
If it’s just one seam or one spot, a repair is usually the better call. Our flat roof repair team in Denver handles those, and we’ll tell you honestly which one you need.
How a flat roof installation works
A flat roof is only as good as the parts you never see. A solid low-slope roof installation comes down to five steps.
Getting down to a sound deck
The old roofing comes off, and any rotted or soft decking gets replaced. Sometimes a new membrane can go over an existing roof, but only if that roof is dry and has just one layer. Covering wet insulation traps moisture that rots the deck from the inside.
Building in drainage
A flat roof isn’t meant to be dead level. It should fall slightly toward a drain, scupper or gutter. When a roof ponds, the fix is usually tapered insulation that builds slope into the roof, plus small peaked sections called crickets that steer water around chimneys and curbs. This is the step that ends ponding instead of just waterproofing over it.
Insulation and cover board
Rigid insulation goes down next, then often a cover board on top. A cover board gives the membrane a firm base, which helps it resist hail and foot traffic, a real plus on the Front Range.
The membrane
The waterproof layer goes on last. For most Denver homes that means one of these:
- TPO, a white membrane with heat-welded seams that reflects summer heat. See TPO roofing in Denver.
- EPDM, a black rubber membrane that stays flexible in cold weather. See EPDM roofing in Denver.
- Modified bitumen, an asphalt-based roll roofing that handles foot traffic well.
Flashing, edges and tie-ins
Most flat roof leaks start at the edges, not in the middle. The membrane gets turned up walls and curbs and sealed, metal edge trim gets fastened along the perimeter, and every pipe and vent gets its own flashing. Where your flat roof meets a shingle main roof, the shingles have to lap over the membrane so water always flows over a seam, never into it.
Building a flat roof for Denver weather
Colorado puts a flat roof through a lot.
Hail is the biggest threat. A steep roof deflects hailstones. A flat roof takes the hit straight on. A firm cover board and a thicker membrane give your roof a better chance of coming through a storm without punctures.
Snow sits longer on a low slope, then melts by day and refreezes at night. Good drainage keeps that meltwater moving instead of freezing in place against a seam. Drains and scuppers also need to stay clear so ice doesn’t back water up.
The sun is stronger at altitude, too. A reflective TPO surface runs cooler, which slows aging and can help keep the room under it more comfortable in summer.
Timing matters as well. Some adhesives and sealants need warm, dry conditions to cure, so a winter install may wait for the right stretch of weather. We’d rather move a date than install in conditions that make the roof fail early.
How it works with APC Roofing
- Book your free inspection. Call 720-902-6940 or request a free online estimate.
- Get a clear, honest assessment and estimate. You’ll see photos of the current roof, find out whether you need a repair or a new roof, and get a written scope that names the insulation, membrane and edge details.
- Get your roof built and the site cleaned up. The crew installs the new roof and hauls away the old material.
If you’d like to spread out the cost, we work with financing partners including Aqua Finance, Fortifi, Hearth and Home Run Finance.
Questions about flat roof installation in Denver
How do I stop water from pooling on my flat roof?
Fix the slope, not just the leak. Tapered insulation and crickets build fall into the roof so water moves to the drains. New membrane alone won’t stop ponding.
Which flat roofing material is best in Denver?
For most homes, TPO or EPDM. TPO reflects heat and has welded seams. EPDM handles cold well. Your deck, your drains and what sits on the roof decide which fits, and you’ll get the reasons with the recommendation.
Can you install a new flat roof over the old one?
Only when the old roof is dry, solid and a single layer. Otherwise it comes off first so you’re not sealing moisture in.
Can you put a flat roof on a small commercial building?
Yes. We install flat roofs on small and light commercial buildings as well as homes.
A flat roof you stop worrying about
Patching a worn-out flat roof year after year usually costs more in the end. Water keeps getting into the insulation and deck between repairs, and the eventual replacement gets bigger. Knowing where your roof stands lets you plan instead of react.
The snow melts off, the spring storms come through, and the ceiling under your addition stays dry. That’s a sound roof, no surprise bill and the confidence you made the right call. For the bigger picture on low-slope roofs, see our flat roofing in Denver page, or call 720-902-6940 to book your free inspection.
