Dormer Loft Conversions in Berkshire
We are a dormer specialist, not a general builder who occasionally does roofs — and across Berkshire that focus shows up in the detailing.
Dormer Loft Conversions — indicative geometry
Dormer Loft Conversions for Berkshire homes
The housing stock around Berkshire runs to Victorian and Edwardian terraces, interwar semi-detached houses and post-war bungalows — so the first question at survey is always which of those you have, because the structure underneath differs completely.
A dormer loft conversion is the whole sequence: steels and a new floor structure, the dormer itself, a compliant staircase, fire-rated doors and a protected escape route, insulation to current Part L, electrics, heating and plaster. Building control sign-off is what turns loft space into habitable floor area on a survey and on a mortgage valuation — and it is the part people skip at their peril.
Key specification
| Floor area gained | 15m² – 30m² typical |
|---|---|
| Head height required | 2.2m+ over the stair landing |
| Structure | Floor steels, ridge beam, new joists |
| Compliance | Part L, Part B fire, Part K stairs |
Planning and building control in Berkshire
Whether you need planning permission or a lawful development certificate depends on the elevation, the volume already used and the local authority's Article 4 position — all of which we confirm before design work starts.
Building regulations approval is separate and always required. We submit the application, book the inspections around the programme and hand you the completion certificate at the end — the document a buyer's surveyor will ask to see.
Why homeowners in Berkshire use us
One quotation covers scaffold, structure, weatherproofing, glazing, plastering and sign-off. You are not coordinating four trades who each blame the last one.
If you want to know what your roof will actually take, the survey is free and there is no obligation attached to it.
Other dormer work in Berkshire
FAQs
Dormer Loft Conversions in Berkshire — FAQs
Can you build a dormer in winter?
Yes, with adjustments. Temporary weather protection over the scaffold lets structural work continue in most conditions. GRP roofing needs dry conditions above about 5°C to cure properly, so in a cold spell we either sequence it differently or specify EPDM, which is unaffected.
How much does a dormer window cost?
A single flat roof dormer typically runs from around £9,000 to £20,000 supplied and fitted, depending on width, cladding finish and access. A full-width rear dormer on a semi is usually £28,000 to £45,000, and a complete dormer loft conversion including stairs, insulation, plaster and building control sign-off is more commonly £40,000 to £70,000. Our online guide-price tool gives you an indicative range in about a minute.
Does a dormer need building regulations approval?
Yes, always — permitted development covers planning, not building control. A dormer needs approval for structure, thermal performance under Part L, fire escape and protected route under Part B, and stairs under Part K if a staircase is involved. We handle the application, the inspections and the completion certificate.
Why is my dormer leaking?
In our experience the window itself is the cause less than a fifth of the time. Far more often it is the apron flashing at the dormer front, the lead soakers where the cheeks meet the roof slope, the back gutter behind a pitched dormer, or a split at an upstand in the flat covering. Water then tracks along a rafter and appears somewhere else entirely, which is why we trace the path before quoting.
Will a dormer add value to my house?
A properly built and signed-off dormer conversion adding a bedroom and bathroom typically returns a meaningful share of its cost in value, and more in areas where floor space is scarce. The building control completion certificate is what makes the space count as habitable floor area on a valuation — without it, surveyors will not include it.
Find out what your roof will take
A free measured survey in Berkshire tells you what is achievable, what it needs, and what it costs — before you commit to anything.