Covering East Grinstead
Alongside East Grinstead, we also cover Horley, Crawley (8 miles to the west) and Crowborough.
Homes in the South East
Many South East homes are inter-war or post-war semis and detached houses with room for rear and side extensions, while historic town centres and villages bring conservation area and listed building controls.
What is included in an upward extension in East Grinstead?
An upward extension adds a new storey on top of an existing house, most often turning a bungalow into a two-storey or chalet-style home. It can double the floor area without using any of the garden.
- Design and planning or prior approval application
- New first-floor structure, walls and roof
- Staircase and changes to the ground floor layout
What will an upward extension cost?
Typical ranges for bungalow and upward extensions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.
| Bungalow and upward extensions | Guide price incl. VAT |
|---|---|
| Chalet conversion with dormers (total) | £45,000 to £85,000 |
| New first floor, standard specification | £2,200 to £2,800 per m² |
| New first floor, good specification | £2,800 to £3,300 per m² |
| New first floor, high specification | £3,300 to £3,800 per m² |
Planning and building rules in East Grinstead
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, Class AA permitted development allows an extra storey on many detached and semi-detached houses built between July 1948 and October 2018, subject to a prior approval application covering design, neighbours’ amenity and other matters. Houses in conservation areas and other protected land need full planning permission, as do most chalet conversions with front dormers.
What can affect an upward extension?
- The staircase takes space from the ground floor plan.
- The house is exposed while the roof is off, so the sequence is planned tightly.
How does the project run?
- Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
- We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
- Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
Questions about an upward extension in East Grinstead
How much does it cost to add a storey?
Around £2,200 to £3,800 per square metre of new floor including VAT, or £45,000 to £85,000 for a chalet conversion with dormers.
How long does it take?
About 12 to 24 weeks on site.
Do you work in East Grinstead?
Yes. East Grinstead is within our coverage for bungalow and upward extensions, along with nearby Horley and Crawley.
Bungalow and upward extensions in nearby towns
- Bungalow and upward extensions in Horley
- Bungalow and upward extensions in Crawley
- Bungalow and upward extensions in Crowborough
- Bungalow and upward extensions in Haywards Heath
Learn more about bungalow and upward extensions, or see every project we cover in East Grinstead.

