What is a rooflight loft conversion?
A rooflight loft conversion (sometimes called a roof window conversion) keeps the existing roof shape and adds roof windows that sit flush with the slope. The floor is strengthened, a staircase is added and the space is insulated and finished.
How much does a rooflight loft conversion cost in Chippenham?
In Chippenham, a rooflight loft conversion typically costs £30,500–£46,000 for a typical rooflight conversion, including VAT at 20% (standard rate). Prices in the South West sit near the national average for this kind of work, and the range for Chippenham reflects that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical rooflight conversion | £30,500–£46,000 |
| Higher specification | £46,000–£57,500 |
The main things that change the cost:
- Number of roof windows
- Fire safety upgrades
- Staircase position
- Storage and finishes
Use the guide price tool to see how size and specification change the figure, then ask for a written, itemised quote.
Do you need planning permission for a rooflight loft conversion in Chippenham?
Whether you need planning permission depends on your house and its location in England. In England roof windows are permitted development if they project no more than 15 centimetres from the roof slope and side-facing windows are obscure-glazed. Listed buildings need consent.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
On a typical rooflight loft conversion we handle:
- Floor joists and any steel beams
- Building control sign-off
- Electrics, heating and plastering
- Insulation between and under rafters
- Head-height survey
- Drawings and structural calculations
How long does it take?
Build time is typically 4 to 6 weeks on site. Design and approvals come first and typically take 6 to 12 weeks, depending on the approval route.
Building in Chippenham
In parts of the South West, protected landscapes and conservation areas shape what can be built, so materials and roof forms are chosen carefully.
Chippenham sits in Wiltshire, about 10 miles north of Trowbridge. We cover the whole of Chippenham, including postcodes SN15.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about rooflight loft conversions in Chippenham
What about fire safety?
The same escape rules apply as for any loft conversion, so a protected stairway and smoke alarms are typically needed.
Is it cheaper than a dormer?
Yes, usually, because the roof shape stays the same. But you gain less full-height floor space.
How much does a rooflight loft conversion cost in Chippenham?
In Chippenham, a rooflight loft conversion typically costs £30,500–£46,000 for a typical rooflight conversion, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Can I have a bathroom?
Yes, where there is enough head height at the shower or bath position.
Who approves a rooflight loft conversion in Chippenham?
Planning matters in Chippenham go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.