What is EPDM roofing?
EPDM stands for ethylene propylene diene monomer, a durable synthetic rubber used on flat and low-slope roofs. It is commonly supplied in large sheets or rolls that are laid over the roof deck and sealed at the seams. Available in black for heat absorption or white to reflect sunlight, EPDM is valued for its flexibility, weather resistance, and long-term performance in varying climates.
Benefits of EPDM roofing
- Longevity: A well-installed EPDM system can last 30 to 50 years with proper maintenance.
- Weather resistance: Excellent resistance to wind, hail, and thermal cycling, plus strong waterproofing capabilities when seams are properly sealed.
- Flexibility: Remains flexible in cold temperatures, reducing the risk of cracks and splits on roof details.
- Cost effectiveness: Generally lower material and installation costs compared with some other flat roofing systems.
- Low maintenance: Simple inspections and occasional resealing extend service life.
- Versatility: Works on many roof shapes, including low-slope designs and odd geometries when installed with liquid or seam systems.
Drawbacks and considerations
- Seam reliability: Field seams must be properly sealed; improper installation can lead to leaks.
- Aesthetic options: Some property owners prefer more reflective or textured surfaces, which can influence material choice.
- UV exposure: Black EPDM absorbs heat; white or reflective variants mitigate heat gain but may come at a premium.
- Repair complexity: Punctures or leaks require localized repair, which may be more involved than some other single-membrane systems.
Types and installation options
EPDM roofing is available mainly in two forms: sheet EPDM and liquid-applied (or coating) EPDM. Sheet EPDM comes in large rolls and is applied with seam tape or adhesives, creating a durable watertight membrane. Liquid-applied EPDM, sometimes called liquid rubber, can be rolled or brushed onto complex shapes for a seamless finish, offering excellent adhesion to irregular substrates. White or light-colored EPDM variants can reduce heat absorption and improve cooling loads for some buildings.
Lifespan, maintenance, and costs
The expected lifespan of EPDM roofing is typically 30 to 50 years under proper maintenance. Routine maintenance includes annual inspections, clearing debris, checking flashings and edges, and addressing any signs of seam fatigue, punctures, or pooling water. Costs vary by region, roof size, and chosen EPDM form. On a typical flat roof, material and installation can range from about $0.80 to $2.50 per square foot for the membrane, with full system installation often falling around $4 to $8 per square foot when including accessories, insulation, and flashing. White EPDM or specialty coatings may be a bit more costly but can reduce cooling loads over time.
EPDM vs other flat roofing materials
| Material | Lifespan | UV resistance | Temperature tolerance | Installation method | Estimated cost per sq ft |
|---|---|---|---|---|---|
| EPDM | 30–50 years | Excellent | -40°F to 180°F | Sheet membranes or liquid coatings | 0.80–2.50 |
| TPO | 15–25 years | Good | -30°F to 180°F | Fully adhered, mechanically attached, or loose laid | 1.50–3.50 |
| PVC | 20–30 years | Very good | -20°F to 200°F | Fully adhered or mechanically attached | 2.50–6.00 |
Choosing a contractor and maintenance tips
When selecting a contractor for EPDM, verify licenses and insurance, request references, and review warranties. Ask about their experience with both sheet EPDM and liquid coatings, and confirm they plan proper seam detailing, flashing, and edge detailing. Maintenance tips include keeping the roof clear of debris, ensuring proper drainage to avoid standing water, inspecting seams and flashings biannually, and reapplying reflective coatings or sealants as recommended by the manufacturer. Regular inspections help maintain long-term performance and warranty eligibility.
Frequently asked questions
How long does EPDM roofing last?
With proper installation and maintenance, EPDM roofs commonly last 30 to 50 years.
Is EPDM roof waterproof?
Yes, when installed correctly with well-sealed seams and flashings, EPDM provides reliable waterproofing for flat and low-slope roofs.
Conclusion
Conclusion, EPDM roofing offers a durable, cost-effective solution for flat roofs, combining flexibility, weather resistance, and relatively simple installation, with maintenance that helps maximize lifespan.
