Most Greenville houses have steep asphalt shingle roofs, but plenty have a flat or low-slope section too: a back-porch roof, a room addition, a dormer top or a carport. People searching for flat roof repair in Greenville, EPDM roofing, flat roof maintenance or low-slope roofing usually have one of these small areas and a leak. Water does not run off a flat roof the way it does off a pitched one, so every seam, edge and penetration has to be sealed, not just overlapped.
This page covers residential flat and low-slope roofs only. We are a referral service, not a roofer, and the licensed local roofer we refer inspects these roofs for free. We have no sourced Greenville price range for flat roofing, so we publish none; ask for a per-square price in writing.
What counts as a flat or low-slope roof
A roof is called low-slope when it rises less than about 3 inches for every 12 inches of run, and flat roofs are built with only a slight pitch so water can drain. Asphalt shingles are designed for steeper roofs. Secondary sources quoting the International Residential Code give 2:12 as the minimum slope for ordinary asphalt shingles, with special underlayment between 2:12 and 4:12. The code edition adopted locally governs, so confirm with the roofer and the permit office. Below that, a membrane or a metal system is used instead.
EPDM vs TPO: the two membranes you will be quoted
EPDM is a synthetic rubber sheet, usually black, that is glued or mechanically fastened and seamed with tape or adhesive. TPO is a thermoplastic sheet, usually white or light gray, whose seams are welded with hot air. Modified bitumen, a rolled asphalt product, is the third option on small residential roofs.
| Membrane | What it is | Seams | Ask the roofer |
|---|---|---|---|
| EPDM | Rubber sheet, usually black | Taped or adhesive | How are the seams and edges sealed, and what is the warranty? |
| TPO | Thermoplastic sheet, usually white | Heat-welded | Which manufacturer, and is the installer certified by them? |
| Modified bitumen | Rolled asphalt layers | Torched or self-adhered | Is torch application used near a wood structure? |
Where flat roofs leak in the Upstate
- Seams and edges where the membrane meets a wall or a drip edge
- Pipe and vent penetrations, the same weak point as on a shingle roof (see the roof repair page)
- Ponding: water standing after rain points to low spots or clogged drains and scuppers
- Flashing where an addition meets the main house, as with a chimney leak
- Punctures from limbs and foot traffic, common under Upstate trees
Flat roof repair or replacement?
A single puncture or a failed seam on a membrane with life left is a repair. Widespread shrinkage, repeated leaks, or wet insulation under the membrane means the section is finished. Wet insulation matters: a membrane patched over wet insulation keeps the problem in. The repair or replace guide gives the rule of thumb we use for pitched roofs, and the same logic applies on a small scale.
What to get in a written flat roof estimate
- The membrane by type and manufacturer, and its thickness
- Whether insulation and decking will be inspected and replaced where wet, priced per sheet (our cost page benchmarks decking at $70 to $100 per sheet)
- How seams, edges and penetrations will be flashed
- Drainage: slope, drains or scuppers, and gutters
- Permit and final inspection, see the permit guide
- A workmanship warranty in writing, separate from the manufacturer warranty
Our roofing services
Related Guides and Services
- Roof repair in Greenville
- Free roof inspection
- Roof replacement cost in Greenville, SC: pitched-roof prices
How Greenville Roofing Experts Works
We are a referral service, not a roofing company. Your request goes to one licensed South Carolina roofer serving the Greenville area, and the referral costs you nothing. See how we vet our pros for the bar that roofer has to clear, read about us and why this arrangement works, or check the answers to common roofing questions. For anything else, contact us.
Flat Roof Questions
How much does flat roof repair cost in Greenville, SC?
We have no sourced Greenville range for flat roofs, so we do not publish one. Ask for the repair priced as a separate line, and compare it with our roof repair prices for shingle roofs.
Is EPDM or TPO better for a flat roof?
Neither wins on every house. EPDM is a rubber sheet with taped or glued seams, TPO has heat-welded seams, and the installer and the seams matter more than the label. Ask for the manufacturer warranty in writing.
Can you put shingles on a flat roof?
Not on a truly flat roof. Sources quoting the building code give 2:12 as the minimum slope for ordinary asphalt shingles, so flat sections use a membrane or metal system.
How do I maintain a flat roof?
Keep drains, scuppers and gutters clear, remove debris and limbs, and have the seams checked once a year. Our free inspection covers flat sections.
Can a leaking flat roof be patched?
Often, if the membrane and insulation underneath are dry and the roof is not near the end of its life. Wet insulation or repeated leaks point to replacing that section.
Sources
We state no flat roof prices because we have no sourced Greenville range. The slope minimum is quoted in secondary sources from the International Residential Code; confirm the adopted edition with the permit office.
- South Carolina Code of Laws, Title 6, Chapter 9 (building codes). Cities and counties must adopt and enforce the state building codes
Get an honest read on your roof
Free inspection, no obligation. Pick a time and a licensed local roofer comes to you.
Schedule My Free Inspection