Dormer Window Installation in Angus and Dundee
We design, build and weatherproof dormer window installation for homeowners across Angus and Dundee, working from first survey through to building control sign-off.
Dormer Window Installation — indicative geometry
Dormer Window Installation for Angus and Dundee homes
Most of the dormer work we take on around Angus and Dundee is on Victorian and Edwardian terraces, interwar semi-detached houses and post-war bungalows, where the ridge height and the position of the existing purlins set the limits.
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 Angus and Dundee
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.
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 Angus and Dundee use us
We would rather tell you at survey that your ridge height will not take what you want than take a deposit and find out in week three.
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 Angus and Dundee
- Dormer Loft Conversions in Angus and Dundee
- Dormer Window Replacement in Angus and Dundee
- Aluminium Dormer Windows in Angus and Dundee
- Dormer Cladding in Angus and Dundee
- Dormer Window Repairs in Angus and Dundee
- Gable-Fronted Dormers in Angus and Dundee
- Full-Width Rear Dormers in Angus and Dundee
- Eyebrow Dormers in Angus and Dundee
FAQs
Dormer Window Installation in Angus and Dundee — FAQs
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.
Will my roof be open to the weather?
No. The roof is only opened once the scaffold, temporary weather protection and materials are all on site, and the dormer is made weathertight — structure, deck, membrane and temporary glazing — before the crew leaves at the end of the opening-up phase. We do not open a roof on a Friday afternoon.
What is the best roof covering for a flat dormer?
GRP fibreglass and EPDM rubber are the two we specify most. GRP cures into a single seamless laminate with bonded trims and suits small tops with several upstands. EPDM is a one-piece membrane that copes better with movement on larger spans. Both carry twenty-year guarantees; mineral felt is cheaper but has a materially shorter life.
What insulation do dormers need?
Current building regulations want around 0.15–0.18 W/m²K for a new dormer roof and 0.18 W/m²K for the cheeks and front. In practice that is a warm-roof build-up using 100–150mm of PIR insulation above or between the structure, with a continuous vapour control layer on the warm side. Getting the VCL continuous matters more than the insulation thickness.
Can you match my existing roof tiles?
Usually. Most common clay and concrete profiles are still in production or available reclaimed, and we source a match at survey stage so you see it before work starts. Where a discontinued profile cannot be matched exactly, we normally recommend taking tiles from a less visible slope for the dormer and using the closest new match on the hidden elevation.
Find out what your roof will take
A free measured survey in Angus and Dundee tells you what is achievable, what it needs, and what it costs — before you commit to anything.