Covering St Helens
Alongside St Helens, we also cover Prescot, Ashton-in-Makerfield (4 miles to the north-east) and Huyton.
Homes in the North West
The North West has long rows of Victorian terraced houses in its towns and cities, alongside inter-war semis and post-war estates, so rear extensions, dormer lofts and kitchen extensions are common projects.
What is a dormer loft conversion?
A dormer loft conversion builds a box-shaped extension out from the rear slope of the roof, creating vertical walls and full head height across most of the new floor. It is the most popular type of loft conversion because it gives the most usable space for the cost.
- Volume calculation and permitted development check
- Dormer frame, roof covering and cladding
- En-suite, electrics and fire-protected escape route
What will a dormer loft conversion cost?
Use these ranges to budget for dormer loft conversions; the survey turns them into a fixed price for the agreed specification.
| Dormer loft conversions | Guide price incl. VAT |
|---|---|
| Rear dormer, bedroom only | £50,000 to £65,000 |
| Full-width dormer with en-suite | £60,000 to £80,000 |
| L-shaped dormer (over rear outrigger) | £65,000 to £90,000 |
Do you need permission for a dormer loft conversion in St Helens?
In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it applies.
In England many loft conversions are permitted development: the extra roof volume must stay within 40 m³ on a terraced house or 50 m³ on a semi or detached house, nothing can sit higher than the existing ridge, no dormer can face a road on the main elevation, and side windows must be obscure-glazed and non-opening below 1.7 m.
What can affect a dormer loft conversion?
- Dormers on the front of the house facing a road are not permitted development in England.
- A flat dormer roof needs proper falls and a quality membrane.
What are the steps?
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
- Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
What people ask before starting
How much does a dormer loft conversion cost?
Typically £50,000 to £80,000 including VAT, and up to around £90,000 for an L-shaped dormer.
Can a dormer include a bathroom?
Yes. The full head height in a dormer makes it the best place for a shower room or en-suite.
Who deals with the council for a project in St Helens?
We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.
Other towns nearby
- Dormer loft conversions in Prescot
- Dormer loft conversions in Ashton-in-Makerfield
- Dormer loft conversions in Huyton
- Dormer loft conversions in Newton-le-Willows
Learn more about dormer loft conversions, or see every project we cover in St Helens.