EPDM Gaskets.
Outdoor gear, steam and hot-water systems, potable-water lines, HVAC air handlers, anywhere weather and ozone chew up other elastomers, EPDM holds.
- HVAC, plumbing, solar, pool and spa, roofing, marine, irrigation, and municipal water treatment all spec EPDM gaskets.
- EPDM is ethylene propylene diene monomer. Saturated elastomer, strong against ozone, UV, weather, and hot water. It cannot tolerate oil.
- We die-cut EPDM gaskets under ISO 9001 from NSF-61 potable-water, peroxide-cured, and FDA-compliant stock.
- Send the flange drawing, service fluid, temperature, and quantity. Cannon Gasket replies with material options, pricing, and lead time.
Need EPDM gaskets? Send us a spec.
What EPDM is and where it fits
EPDM (ethylene propylene diene monomer) is a synthetic rubber built from ethylene, propylene, and a small amount of diene monomer. The combination gives it three properties that matter for sealing applications: broad temperature range, excellent resistance to ozone and UV, and compatibility with water and steam. It is the elastomer of choice across plumbing, HVAC, solar thermal, roofing, potable water systems, and brake-fluid sealing.
EPDM has one disqualifying weakness you need to know up front: it does not tolerate petroleum oils, fuels, or hydrocarbon hydraulic fluids. If there's any chance of oil contact in your application (even intermittent splash from an adjacent system), spec Nitrile (Buna-N) or Viton® instead.
When EPDM is the right call
- Outdoor and weather-exposed sealing. EPDM is the benchmark for ozone, UV, and weather resistance. Outdoor enclosures, solar panels, roofing systems, irrigation fittings. EPDM outlasts Nitrile and Neoprene by years.
- Steam and hot water.Compatible with saturated steam up to ~300°F. Standard on plumbing fixtures, boiler flanges, and potable-water (NSF-61 grades).
- Brake fluid (DOT 3/4). EPDM is the only common elastomer chemically compatible with glycol-based DOT brake fluid. Run Nitrile here and you get rapid swell and failure.
- Dilute acids and alkalis. Good resistance to household and mild industrial cleaning chemistries.
- Low-temperature flexibility.Stays flexible down to -70°F. That's better than Nitrile in cold climates.
When EPDM is the wrong call
- Any petroleum contact. Oils, fuels, greases, hydraulic fluids, and solvents attack EPDM aggressively. See Buna-N/Nitrile for oil-contact applications.
- Above +300°F continuous.EPDM tops out around +300°F. For higher temperatures consider Silicone(to +500°F) or Graphite(to +1000°F).
- FDA and USP Class VI medical. EPDM has FDA grades but is less common than Silicone for regulated medical work.
Key specifications at a glance
These are the EPDM properties Cannon Gasket's engineering team works with most often. For full durometer ranges, thicknesses, and certifications available, see the EPDM Rubber Gaskets product page.
- Continuous temperature range:-70°F to +300°F (-57°C to +149°C)
- Durometer: 40A to 80A Shore hardness (softer and harder grades available on request)
- Compression set: Low; EPDM holds sealing force well across thermal cycles
- Typical certifications: FDA 21 CFR 177.2600, NSF-61, AMS 7338, UL-157 flame grades
EPDM vs. the alternatives
When EPDM doesn't fit, one of these is usually the right substitute.
- Buna-N / Nitrile. The right call when oil or fuel is in contact. Higher petroleum resistance, lower ozone resistance than EPDM.
- Silicone. Wider temperature range (to +500°F), FDA and USP Class VI medical grades, better UV resistance than EPDM. Costs more and carries lower mechanical strength.
- Neoprene. Balanced oil and weather resistance, inherently flame retardant. A compromise pick when both environments are in moderate play.
- Viton®. Broader chemical resistance. Handles aggressive hydrocarbons and high temperatures. Significantly higher cost.
Common EPDM gasket applications
- Plumbing fixtures (faucets, valves, potable water fittings)
- HVAC systems: air handlers, ductwork, condensate drains, condenser coil gaskets
- Automotive cooling systems, brake fluid reservoirs, heater cores
- Irrigation valve seals and riser gaskets
- Roofing membrane seals and solar panel mounting gaskets (long-term UV / ozone / thermal cycling)
- Outdoor enclosures, junction boxes, NEMA-rated electrical boxes
- Water treatment systems, filter housings, pool & spa equipment
Manufacturing and sourcing from Cannon Gasket
Cannon Gasket has die-cut EPDM gaskets from sheet stock since 1971. We stock standard commercial and FDA-compliant EPDM in a range of durometers and thicknesses, and we cut to customer drawings with standard ±0.010" to ±0.015" OD/ID tolerances. PSA (pressure-sensitive adhesive) backing, pad printing to MIL-STD-130, custom packaging, and JIT/VMI/Kanban programs are all on the menu.
For dimensional specs, durometer grade options, certification availability, and a formal quote:
See EPDM product specs → Request a Quote
Related resources
- Gasket material selection guide. Full decision framework across every compound.
- Material comparison tool. Side-by-side EPDM vs. other elastomers.
- Durometer / hardness chart
- EPDM rubber washers. Same compound, die-cut as washers.