Chapter 1: Why are slates slipping off the roof of our Victorian railway terrace in Eastleigh?
What we find
Slates are hung from small holes near the top edge, fixed with a nail into a timber batten (the thin timber strip the slates hang from). On terraces from the railway-works era the original nails were iron, and iron rusts with age and damp. Over a century the nail shank thins until the slate slides a few millimetres, then drops. Whole rows can go like this, because every nail on the roof is the same age.
You may notice a slate on the path or in the front garden, or a dark gap in the pattern from the street. Inside, a brown stain on the ceiling below the slope usually follows within a season or two. The slates themselves are often sound; the fixings have failed and the lower part of the roof is carrying the load.
What we fix
We start with a survey from ladders and the loft, photographing the slope, and tapping slates to hear which are cracked. Where the fault is local, we remove the loose slates, renew the battens beneath where they are soft, and re-fix with copper or stainless nails so the problem does not return. Matching replacements are sourced from reclaimed stock where the slates are old and worth keeping.
If the whole slope is failing, re-slating is the honest answer, using the old slates again where they are sound. Published UK guides put one slate repair at £100 to £250 of labour, a slate at £5 to £25 and an access tower or scaffold at £300 to £800; your fixed quote follows the survey. Our slate roofing page covers the choices in more detail.