Duradek

Duradek is a Canadian manufacturer that has been making the same category of product since 1974: a reinforced vinyl membrane that waterproofs a structure in a single layer.

Up north that membrane is often left exposed and lived on. On this coast the sun takes it apart, so almost nobody does — since we started installing it, one customer has left a deck bare. Everything else gets tile or decking laid over the top, and the Duradek disappears underneath. Which means the thing you are buying is the layer you will never see again.

Why this one is installed rather than sold

A membrane does not fail in the middle of a sheet. It fails at a seam, at a drain, or where it turns up a wall, and every one of those is made on site with a hot-air welder rather than in a factory. That is why the manufacturer restricts who may install it, and why the warranty is conditional on an authorized applicator doing the work.

SRQ Modern is one. It also means the surface is specified, supplied and laid by the same trade, so there is nobody to point at if water gets past it.

Where it belongs on this coast

Balconies, rooftop terraces, stair landings, and any deck built over a room somebody sleeps in. That last case is the one that matters here and the one that is unforgiving: a leak in a balcony over living space announces itself as a stain on a ceiling, long after it started.

Vinyl decking and balcony waterproofing has the detail — slope, permits, going over an existing deck, and how long a membrane actually lasts.