Roofing Screw EPDM 16mm Washer – Bag 100

The 16mm washer roofing screw is one of those things that gets taken for granted right up until you use the wrong one. These self-drilling tek screws come with a bonded EPDM rubber washer that compresses on installation, creating a watertight seal around the fixing point. No separate washers to drop in the gutter, no fiddling about on a cold roof. The washer does its job quietly and stays put.

Available in 5.5mm and 6.3mm shank diameter, these screws are suited to fixing profiled metal sheets, corrugated roofing panels and metal cladding to steel or timber substructures. The self-drilling tip means no pre-drilling on lighter gauge steel, which speeds up the job considerably when you’ve got a full roof run to get through. Sold in bags of 100, they’re priced for trade use rather than the single-sheet DIY merchant who needs four.

Why the EPDM Washer Matters on a Roofing Screw

EPDM rubber holds up well outdoors. It handles UV exposure, temperature swings and standing water far better than basic rubber alternatives, which tend to harden and crack over a few seasons and then let water track down the shank. Once that starts happening, you’ve got a leak that looks like it’s coming from somewhere else entirely. Using a 16mm washer roofing screw with a properly bonded EPDM seal is one of the easier ways to avoid that particular conversation with a client.

The 16mm washer diameter gives solid bearing coverage across the sheet profile without over-compressing onto thinner materials. Get the torque right and the washer seats firmly without distorting. Too tight and you’ll mushroom the washer out past its effective seal zone, which defeats the purpose. A clutch-controlled driver or a low-torque setting on a cordless drill will do the job cleanly.

These are a straightforward, reliable fixing. Bag of 100 keeps the van stocked without taking up half a shelf.