When we supply roofing and cladding distributors across Europe, one detail gets overlooked: the washer. The screw holds the sheet down; the washer is what keeps the weather out. As a screw factory, here are the six reasons we always spec EPDM rubber washers on roofing screws.
A correctly chosen and seated EPDM washer fully seals the drilled hole, giving a weather-tight surface against rain, wind and dust. Skip it and you invite slow leaks that are expensive to chase down later.
The washer acts as a cushion between the screw flange and the metal sheet, spreading clamping pressure instead of denting one point. That means a flatter, more secure fix.
Under high winds or thermal movement, that cushion lets the sheet flex slightly and release stress instead of fighting the fastener. Fewer fatigue failures over the roof's life.
Metal roofing is colour-coated, and so are quality screws. Without a washer, the two coatings scrape on contact and rust starts almost immediately. The rubber seat protects both finishes.
EPDM is non-conductive — it resists electrical current, ozone and sunlight, and cuts the risk of galvanic corrosion when dissimilar metals meet. A quiet but real longevity win.
PVC washers are lighter and cheaper and show up on budget zinc-plated screws, but they're stiffer and age faster outdoors. EPDM stays flexible and outlasts the sheet it's fixing — which is the whole point.
Screws are a tiny fraction of roof cost, yet they decide how long the sheets last. We're a screw factory supplying European distributors and OEMs, and we accept custom orders — send us your diameter, length, head, coating and washer spec and we'll match it, prototype, and quote. Every batch ships with an MTC on request.
Contact us now for samples: support1@tianyufasteners.com. Explore our offerings at www.tianyufasteners.com.
Q: Do you supply roofing screws with EPDM washers to our specification? A: Yes. As a factory we supply self-drilling roofing screws with EPDM washers in your required diameter, length, head and coating, and we accept custom orders from drawing or sample.
Q: EPDM vs PVC washer — which do you recommend for European climates? A: For outdoor longevity we recommend EPDM: it stays flexible through temperature cycles and resists UV and ozone. PVC suits budget jobs but cracks sooner in open weather.
Q: Will the washer actually stop leaks on colour-coated metal sheet? A: Yes — the EPDM seat seals the puncture and cushions the coating so it isn't scraped on install, which is exactly where rust normally begins.
Q: What documents support a European shipment? A: Every batch ships with a Material Test Certificate, plus dimensional inspection and salt-spray reports on request for your compliance file.