Post-war and 1960s housing — the estates and infill that fill places like Hounslow, Wembley, Bexley and Dartford — marked a turning point: cavity walls became the norm, flat-roof extensions appeared, and a handful of homes were built with non-traditional methods. The good news is that most respond very well to a few low-cost measures. The catch is checking the construction first.
The post-war house: a thermal profile
- Cavity walls in most cases — often fillable, the single biggest opportunity.
- Thin or original loft insulation — usually well below today's 270mm standard.
- Suspended timber or solid concrete floors — depends on the build; both can be insulated.
- Flat-roof extensions and porches — frequent cold spots that get overlooked.
- Larger windows and thinner construction than pre-war stock — more glazed area to lose heat.
- Occasional non-traditional construction — concrete panel or steel-frame systems that need specialist assessment.
What to do, in order
- Loft top-up to 270mm — cheapest, fastest payback.
- Cavity-wall insulation — if the wall is a clear, suitable cavity, this is excellent value.
- Floor insulation — suspended or solid, depending on the build.
- Flat-roof extensions — upgrade any cold flat roof, ideally at re-cover stage.
Cavity walls — but check first
Most 1960s homes have a cavity that can be filled relatively cheaply, which is why wall insulation is often far less disruptive here than on a solid-wall period home. But the cavity must be clear, dry and wide enough — and the wall must be standard masonry. Where it isn't suitable, the fallback is external or internal wall insulation; see the EWI vs IWI guide. A survey confirms which route applies before any work is quoted.
Lofts & flat roofs
The pitched loft is a standard top-up to 270mm — see the loft insulation guide. The bigger blind spot in post-war homes is the flat-roof extension: kitchens, utility rooms and porches with cold, uninsulated flat roofs. These are best treated with a warm-roof build-up when the covering is renewed.
Non-traditional construction
A minority of post-war homes — particularly ex-local-authority stock — were built with concrete panels, steel frames or other non-traditional systems rather than brick-and-block cavity walls. These can't be cavity-filled in the usual way and need a tailored solution, often external wall insulation designed around the structure. If you're unsure what your home is built from, that's exactly what the free survey establishes.
What to watch for
- Confirm the cavity is suitable — don't assume every 1960s wall can be filled.
- Identify non-traditional construction early — it changes the whole approach.
- Don't ignore the flat roof — it's the most commonly missed cold spot.
- Check existing cavity insulation — some homes were filled decades ago with material that has since slumped or failed.
- Floor type varies — establish whether it's suspended timber or solid concrete before specifying.
Insulating other property types
1960s house insulation FAQs
Do 1960s houses have cavity walls?
Most post-war and 1960s homes were built with cavity walls, which can often be insulated by filling the cavity where it is clear, dry and wide enough. A minority used non-traditional methods such as concrete panels or steel frames, which need a different approach — so the wall is always checked first.
What is the best insulation for a 1960s house?
Usually a loft top-up to 270mm, cavity-wall insulation if the wall is suitable, suspended or solid floor insulation, and dealing with any cold flat-roof extension. These homes generally respond very well to a few low-cost measures because the cavity and roof are the main weak points.
Can every 1960s house have cavity wall insulation?
No. The cavity has to be clear of debris, wide enough, and free of damp, and the wall must be standard masonry rather than a non-traditional system. Where the cavity is unsuitable or already filled, external or internal wall insulation is the alternative.
How do you insulate a flat-roof extension from the 1960s?
A cold, uninsulated flat roof is best upgraded with a warm-roof build-up — rigid insulation above the deck — ideally when the roof is being re-covered. Where that is not possible, insulation can sometimes be added below, with careful condensation control.