Cat Slide Dormers in Hampshire
Our teams install cat slide dormers throughout Hampshire, handling structure, weatherproofing, glazing and finish as one job with one point of contact.
Cat Slide Dormers — indicative geometry
Cat Slide Dormers for Hampshire homes
Because Hampshire 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 cat slide (or 'sweeping') dormer lets the main roof plane run on below the dormer sill, so the dormer appears to emerge from the roof rather than to be planted on it. It is a rural and cottage idiom, and it works beautifully on long, low roofs where a box dormer would look brutal. Detailing at the sill and the sweeping valley is the whole job.
Key specification
| Typical width | 1.2m – 3.0m |
|---|---|
| Sweep | Main roof continues below sill line |
| Roof finish | Plain tile, slate or pantile |
| Critical detail | Swept valley and sill flashing |
Planning and building control in Hampshire
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 Hampshire 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 Hampshire
FAQs
Cat Slide Dormers in Hampshire — FAQs
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.
Do you handle the planning application?
Yes. We prepare measured drawings, elevations and sections, submit the application or the lawful development certificate, and deal with the case officer's queries. On conservation and listed work we also put together the heritage justification the application needs.
What is the difference between a dormer and a Velux?
A rooflight sits flush in the roof slope and gives you light without any extra height — you still have a sloping ceiling. A dormer projects out from the roof and creates vertical walls with a level ceiling behind them, so you gain genuinely usable standing space and floor area, not just daylight.
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.
Find out what your roof will take
A free measured survey in Hampshire tells you what is achievable, what it needs, and what it costs — before you commit to anything.