1930s & Interwar Semis

Hipped clay-tile roofs, mortar ridges and bay windows — ninety years old and very fixable.

Britain built more houses between the wars than in any period before or since, and our coverage area got a generous share: the Metroland avenues of North-West London and Watford, the outer rings of Birmingham and Leicester, and the leafy semis of Sutton Coldfield and Solihull. If your house is a bay-fronted semi with a hipped roof, this is your page.

The interwar roof, part by part

The covering is clay tile — often very good clay tile, which is why so much of it is still up there at ninety. The weak points were never the tiles; they're everything bedded in mortar. Ridges along the top, hips down the corners: all mortar, all cracked or crumbling by now, all on at least their second re-bedding. Underneath sits the era's felt (where there is any), typically brittle enough to crumble, and at the front sits the signature failure of the whole type — the bay window roof, a small, shallow, heavily-flashed structure that leaks into the front bedroom quietly for years before anyone connects the damp patch to it.

What we do on these houses

Ridge and hip re-bedding — or better, dry-fix conversion that removes the mortar problem permanently — tile refixing and matching, bay roof re-covering and flashing renewal, and the era's tired timber rooflines replaced in uPVC. When the whole covering is ready, strip-and-relay is the interwar speciality: your original clay tiles lifted, new underlay and battens fitted, the same tiles relaid. The street looks unchanged; the roof underneath is new.

Repair options

Repair or replace

Interwar clay tiles routinely outlive the roof they're nailed to, so "replace" here often means replacing everything except the tiles. Genuine full replacement only earns its keep when the tiles themselves are delaminating — frost damage flaking the faces off — and we'll show you close-up photographs before that word enters the conversation.

Our process

How we do it

Hips are the tell on a thirties roof, so that's where our survey starts: their mortar, their irons, the straightness of their lines. Then ridges, valleys, the bay, the felt from inside the loft. Twenty minutes of looking in the right order gives an honest picture of whether this roof needs a morning's pointing or a bigger conversation.

Common questions

Frequently asked

The hips on our semi have wavy lines of fresh mortar — previous repairs? +

Almost certainly, and it's the most common sight on interwar roofs: generations of re-bedding, each lasting a decade or so. There's no shame in another round, but if you're paying for it a third time, a dry-hip system is the version of the repair that doesn't recur — mechanically fixed, no mortar to crack.

Why does the front bedroom get damp but nowhere else? +

Look at the bay. Its little roof takes weather badly — shallow pitch, lots of flashing per square metre, and junctions on three sides. It fails quietly and drips into the front bedroom or the bay ceiling below. It's a contained repair, and one we do constantly on this housing type.

Strip-and-relay or new tiles — how do we decide? +

By survival rate. We assess what proportion of your originals will lift cleanly (good clay usually manages 80–90%), price the relay with reclaimed matches for the casualties, and price new tiles alongside. Originals usually win on both cost and looks — but the numbers make the decision, not sentiment.