Dormer Window Installation in Surrey
From the first measured survey to the completion certificate, we run dormer window installation projects in Surrey as a single, managed piece of work.
Dormer Window Installation — indicative geometry
Dormer Window Installation for Surrey homes
Roofs across Surrey are dominated by large interwar detached and semi-detached houses with generous roof spans, and that mix decides almost everything about what a dormer here needs to look like and how it has to be built.
Installing into a dormer is not installing into a wall. The opening sits in a lightweight timber frame that may have moved, the sill needs a positive fall and a proper drip, and the head has to be flashed back under the cheek cladding. Getting a dormer window in square, sealed and draining is a different skill from a ground-floor replacement.
Key specification
| Frame materials | uPVC, timber, aluminium or composite |
|---|---|
| Glazing | A-rated double or triple glazed |
| Sill | Positive fall with stooled ends and drip |
| Sealing | Compressed foam tape plus low-modulus silicone |
Planning and building control in Surrey
If the property is in a conservation area or the dormer faces the road, a full planning application is needed. We prepare the drawings and handle the submission either way.
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 Surrey use us
Everything is priced from a measured survey, not a phone call — which is why our quotations tend to be the ones that still hold at the end of the job.
Book the survey, get the fixed written price, and decide in your own time. Nothing about that process commits you to anything.
Other dormer work in Surrey
FAQs
Dormer Window Installation in Surrey — FAQs
Do you work on listed buildings and in conservation areas?
Yes. That work is detail-led: matching sightlines, glazing bar widths, cill projections and cheek finishes to what survives, and specifying timber, lead and natural slate rather than modern equivalents. We prepare the drawings and heritage statement for listed building consent alongside the planning application.
Can a dormer include an en-suite?
Very often, yes — a full-width or L-shaped dormer usually has enough floor area for a bedroom plus a shower room. The practical constraints are getting soil and waste down to an existing stack, and whether the head height over the shower tray works. Both are settled at survey.
What happens to my existing loft insulation?
It comes out. Insulation at ceiling-joist level is in the wrong place once the loft is a room — the thermal line moves up to the new roof and dormer build-up. We remove and dispose of the old quilt and insulate the new envelope, which is also what makes the room comfortable to use in August.
How long does a dormer take to build?
A single box or flat roof dormer is typically three to five weeks on site. A full-width rear dormer runs five to eight weeks, and an L-shaped dormer on a terrace with an outrigger is closer to seven to ten. A complete dormer loft conversion including the staircase, services and finishes is usually eight to twelve weeks from scaffold up to sign-off.
Can you build a dormer on a bungalow?
Usually yes, and bungalows often give the best results because the spans are wide and there are no party walls. The deciding factor is ridge height: you generally want at least 2.6m from the top of the ceiling joists to the underside of the ridge. We measure this at survey before committing to anything.
Find out what your roof will take
A free measured survey in Surrey tells you what is achievable, what it needs, and what it costs — before you commit to anything.