Dormer windows in Downpatrick
We design, build and weatherproof dormer windows and dormer loft conversions for homeowners across Downpatrick, working from first survey through to building control sign-off.
What we build in Downpatrick
Downpatrick is a mix of Victorian and Edwardian terraces, interwar semi-detached houses and post-war bungalows, and each of those wants a different dormer form — which is why we survey before quoting rather than pricing off a photograph.
Whether that is a single flat roof dormer to make a back bedroom usable, or a full-width rear dormer with a bedroom and en-suite, the process is the same: a free measured survey first, a fixed written price second, and nothing else until you have both in front of you.
Planning permission in Downpatrick
Rear dormers on houses often sit inside permitted development, but the volume allowance is consumed by any previous loft or rear extension — so we check the planning history for the address before we say yes.
Downpatrick sits in County Down, and local authority interpretation of the volume allowance does vary — which is why we check the planning history at your specific address rather than assuming the neighbours' dormer sets a precedent.
How the job runs
Scaffold and protection
Scaffold designed, erected and inspected. Temporary weather protection over the work area before anything is opened.
Weatherproofing
Deck, insulation, membrane or lead, cheek cladding, flashings and gutters — the dormer is weathertight from this point.
Finish and sign-off
Plaster, electrics, decoration and making good, final building control inspection and your completion certificate.
Design and consent
Measured drawings, elevations and sections. We submit the planning application or lawful development certificate and the building regulations application.
One quotation covers scaffold, structure, weatherproofing, glazing, plastering and sign-off. You are not coordinating four trades who each blame the last one. 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.
Popular in Downpatrick
Dormer work we are asked for most
Sash Dormer Windows
Vertical sliding sashes sized and detailed for a dormer opening.
Learn moreLead & Zinc Dormer Roofing
Traditional code lead and standing-seam zinc for dormer roofs, cheeks and flashings.
Learn moreGable-Fronted Dormers
A pitched dormer with a vertical gable face — the classic 'dog-house' front elevation.
Learn moreL-Shaped Dormers
A rear dormer joined to a second over the outrigger — the Victorian terrace answer.
Learn moreDormer Loft Conversions
The full job — structure, dormer, stairs, insulation, plaster and building control sign-off.
Learn moreDormer Window Replacement
Swap tired, draughty or rotten dormer windows without touching the structure.
Learn moreFAQs
Dormers in Downpatrick — FAQs
How disruptive is a dormer build?
Less than people expect, because most of the work happens above your ceilings and is reached from the scaffold. The noisy phases are opening up and installing steels, typically two to four days. Once the staircase is cut in there is dust and traffic through the house, and we sheet and protect the route for that period.
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.
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.
Do I need planning permission for a dormer window?
Rear dormers on a house often fall under permitted development, provided the dormer is set at least 200mm back from the eaves, sits below the ridge line, uses materials similar in appearance to the existing house, and stays within the volume allowance — 40m³ for a terrace, 50m³ for a semi or detached. Front-facing dormers, flats and maisonettes, listed buildings, conservation areas and any property with an Article 4 direction all need a full planning application. We check the constraints on your specific address before we quote.
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.
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.
Find out what your roof will take
A free measured survey in Downpatrick tells you what is achievable, what it needs, and what it costs — before you commit to anything.