Covering Harpenden
We work in Harpenden (AL5) and the places around it, including St Albans, Luton and Hemel Hempstead.
Homes in the East of England
Across the East of England, newer estates often have integral garages and room for rear extensions, while older towns have Victorian terraces and conservation areas that shape what can be built.
What is 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.
- Structural steel to remove the side wall
- Drainage and new gully positions
- Underfloor heating ready screed if wanted
How much does a side return extension cost in Harpenden?
What side return extensions typically cost. These are guide ranges; the written quote for your house replaces them.
| 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 Harpenden?
English projects need planning clearance from the local council, building regulations sign-off from building control, and party wall notices where the work is on or near a shared boundary. We prepare and manage all three.
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 should I think about before starting?
- Glazed roofs need careful detailing against the neighbour’s wall.
- Many terraces sit in conservation areas, where side extensions need planning permission.
From first call to completion
- 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.
Is a glazed roof too hot in summer?
Modern solar-control glass and a mix of glazed and solid roof keep it comfortable. We advise on the balance during design.
Do you work in Harpenden?
Yes. Harpenden is within our coverage for side return extensions, along with nearby St Albans and Luton.
Also covering
- Side return extensions in St Albans
- Side return extensions in Luton
- Side return extensions in Hemel Hempstead
- Side return extensions in Welwyn Garden City
Learn more about side return extensions, or see every project we cover in Harpenden.