Covering Seaford
Seaford is about 11 miles east of Brighton. We also cover Rottingdean (8 miles to the west), Eastbourne and Hailsham.
Homes in the South East
The South East has a lot of 1930s and post-war semi-detached housing, well suited to rear extensions and hip-to-gable loft conversions, alongside period properties in conservation areas that need a more careful design.
What goes into a side return extension?
Side returns are small in area but heavy in detail: party walls, a glazed roof, and steelwork to take out the original back wall. We design the roof for light and drainage, agree the party wall process early, and keep the work tidy because access is often through the house.
- Glazed or solid roof with rooflights
- Underfloor heating ready screed if wanted
- Plastering and making good to the old house
How much should I budget for a side return extension?
Indicative costs for side return extensions. London and the South East usually sit towards the top of each range.
| Side return extensions | Guide price incl. VAT |
|---|---|
| Standard specification | £3,350 to £3,700 per m² |
| Good specification | £3,700 to £4,150 per m² |
| High specification | £4,150 to £4,550 per m² |
How is a side return extension approved in Seaford?
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 a single-storey rear extension can often go ahead under permitted development: up to 3 m deep on an attached house or 4 m on a detached one, no higher than 4 m, with eaves no higher than 3 m within 2 m of a boundary. Deeper extensions, up to 6 m or 8 m, need prior approval from the council first.
What can change the price or programme?
- Access is often through the house, so we plan deliveries and protect floors.
- Glazed roofs need careful detailing against the neighbour’s wall.
What happens after I enquire?
- 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.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
What people ask before starting
Does a side return need planning permission?
In England it can be permitted development if it is single storey, no higher than 4 m and no wider than half the original house. Conservation areas are the main exception.
How long does a side return take?
About 10 to 14 weeks on site.
How do I get a price for side return extensions in Seaford?
Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.
Also covering
- Side return extensions in Rottingdean
- Side return extensions in Eastbourne
- Side return extensions in Hailsham
- Side return extensions in Brighton
Learn more about side return extensions, or see every project we cover in Seaford.

