You notice it first as a stain on the landing ceiling after a wet week, or a slipped slate lying in the border off Station Road. Nothing dramatic. Then autumn proper arrives and you start wondering what’s going on up there. A story from Roofing Today this week is a handy reminder of how much of a roof’s life comes down to the boring bits: Liverpool Street station has just had its Victorian trainshed re-roofed over two years, with 770 glazed panels replaced and the guttering and rainwater capacity beefed up.
Now, your semi in Wadhurst isn’t an 11,000 square metre trainshed. But the lesson carries over. The contractor on that job put the drainage right alongside the covering, because lichen and standing water were what had killed the old panels in the first place. On a house it’s the same story. Moss-choked valleys, a gutter that’s lost its fall, a downpipe silted solid. Water has to go somewhere, and if it can’t go down the pipe it goes under the slate.
So what do we look at on a roof repair? Slate first: how many are slipped, cracked or held on by rusted nails, and whether the batten gauge still suits the slate size, because a 300mm slate needs a different gauge to a 500mm one and a 75mm head lap is the minimum we like to see. Then the details. Verges that want re-pointing or a dry verge system, hips and ridges bedded on mortar that’s gone sandy, and flashings. Old lead around a chimney is often Code 3 or less and worn paper-thin; Code 4 or 5 on a new stack flashing, with a proper soaker at each course, will see out decades. Any felt laps underneath should be at least 150mm, and the breather membrane shouldn’t be sagging into the battens.
The other thing the station job got right was working without shutting the place down. Most of our repairs in Wadhurst, Ticehurst and out towards Crowborough are done from a roof ladder or a couple of scaffold lifts, in a day or two, with the family carrying on as normal.
If you’ve spotted a stain, a slipped slate or a gutter overflowing, get it looked at before the winter gales do the deciding. Mastercraft Roofing cover Tunbridge Wells, Wadhurst, Tonbridge and Crowborough, and you can see their work and get in touch at https://mastercraftroofing.co.uk/.