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Full-Width Rear Dormers in Northumberland

Our teams install full-width rear dormers throughout Northumberland, handling structure, weatherproofing, glazing and finish as one job with one point of contact.

Free measured surveyA specialist visits, measures and tells you what the roof will and will not take.
Fixed written priceOne quotation covering structure, scaffold, weatherproofing, glazing and making good.
Building control managedWe submit, book the inspections and hand you the completion certificate.
Insured and guaranteed£5m public liability, ten-year structural and twenty-year flat roofing guarantees.
Nationwide coverageDirectly employed and vetted specialist teams across England, Wales, Scotland and Northern Ireland.

Full-Width Rear Dormers — indicative geometry

Full-Width Rear Dormers for Northumberland homes

Because Northumberland is largely Victorian and Edwardian terraces, interwar semi-detached houses and post-war bungalows, the roof pitches and span widths we meet are fairly predictable, and that makes feasibility a quick conversation rather than a guess.

A full-width rear dormer runs from party wall to party wall, squaring off the entire rear slope. On a standard terrace or semi it typically converts 12–18m² of crawl space into full-height room — enough for a double bedroom and an en-suite. Set back 200mm from the eaves and 500mm below the ridge, it usually falls inside permitted development on a house that has not been extended before.

Key specification

Typical projection4.0m – 8.0m wide
Set-back200mm from eaves, 500mm below ridge
StructureSteel ridge beam plus floor steels
Roof finishGRP, EPDM or single-ply membrane
Indicative guide prices. Our online tool gives a realistic range in about a minute — pick your dormer type, width, finish and scope. Get an indicative price →

Planning and building control in Northumberland

Getting the consent route right at the start saves months. We establish whether it is permitted development, a lawful development certificate or a full application on the first visit.

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 Northumberland use us

The completion certificate is part of the deliverable, not an afterthought. It is the document that makes the space count when you come to sell.

Send us the address and roughly what you are hoping to gain, and we will come back with a realistic answer rather than an optimistic one.

Other dormer work in Northumberland

FAQs

Full-Width Rear Dormers in Northumberland — FAQs

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.

Can I put a dormer on the front of my house?

Front-facing dormers are not covered by permitted development and always need a full planning application. Approval depends heavily on the street scene — planners look at whether other dormers already exist on the road, and at proportion, position and materials. Hipped and pitched forms are approved far more often than flat boxes on a front elevation.

Read all frequently asked questions →

Find out what your roof will take

A free measured survey in Northumberland tells you what is achievable, what it needs, and what it costs — before you commit to anything.

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