Episode Details

DD explains what keeps a membrane holding and what finally breaks it. A membrane can hold for years, but once the first crack opens, the water finds the weak point and goes through all at once, in a matter of seconds. The question at the centre of the episode is whether you can see that failure coming, and what to check before it happens.

You will come away with the two signs DD watches for. The first is a surface that goes soft and gives under your thumb, a warning DD says most people miss. The second is the dull patch: a good membrane shines, while a tired one goes matte about a week before it fails. DD calls that the only rule worth trusting, and explains why it gives you time to act before the membrane lets go.

00:00 Intro
00:07 Why