Bend Aluminum Trim Coil
Folding trim coil to a crisp straight line in place — a light knife score and a block instead of a brake.
Patch a Hole in a Rubber Flat Roof With Primer, Seam Tape and Two Coats of Sealant
Technique: Patch a Rubber Flat Roof
The Problem
A rubber flat roof — EPDM, or a liquid-applied equivalent — fails at points, not across the field. A dropped tool, a fixing that worked loose, or an old seam lets water past in one small place, and the water then travels under the membrane where you can't see it. The leak inside is rarely under the hole.
Patching a membrane badly is worse than the hole. Sealant smeared over a puncture bridges it and then cracks, because a flat roof moves constantly with temperature and a rigid patch over a flexible membrane has to fail somewhere.
The Technique
- Clean the damaged area thoroughly. Everything that follows is an adhesive bond, and it's only as good as the surface — dirt, moss and old sealant residue all have to come off, and the area must be dry.
- Brush EPDM primer around and over the damage. Rubber membranes are low-energy surfaces and coatings won't grip them reliably without it.
- Apply seam tape over the damage, bedding it down so there are no bubbles or lifted edges.
- Coat it with waterproof sealant, extending past the tape onto the primed area.
- Lay geotextile over the wet sealant and press it in.
- Apply a second coat of sealant over the geotextile, working it through the fabric until it's fully wetted out and no dry fibres show.
The same sequence works along a seam that's opened up, not just over a puncture.
Pro tip: The geotextile is the reason the patch survives. Sealant alone cures to a film that stretches only so far before it splits; the fabric embedded in it spreads movement across the whole patch instead of concentrating it at the edge of the hole. Skipping that layer is what makes a patch that looks perfect and reopens in a year of temperature cycling.
Pro tip: Extend each layer further than the one beneath it, so the patch steps outward as it builds. A stack of layers all ending on the same line gives water a single edge to work at; stepped edges give it nowhere obvious to start.
Safety note: Flat-roof work is roof work — a wet membrane with fresh sealant on it is genuinely slippery, and the edge is unprotected. Sort out access and edge protection before carrying materials up, and don't patch in the rain or when the surface won't be dry long enough for the primer to flash off; a patch applied over damp is a patch that peels.
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