Covering Harpenden
Harpenden is about 5 miles north of St Albans. We also cover St Albans (5 miles to the south), Luton and Hemel Hempstead.
Homes in the East of England
Housing in the East of England ranges from post-war estates and modern developments to timber-framed and period homes in historic towns, so permitted development checks and conservation controls both feature regularly.
What is included in a wraparound extension in Harpenden?
A wraparound extension combines a side return and a rear extension into one L-shaped build, giving the biggest possible ground-floor space on terraced and semi-detached houses. It usually creates a large open-plan kitchen, dining and living area across the back of the house.
- Pitched, flat or glazed roof with rooflights
- Glazing, insulation, plastering and electrics
- Optional kitchen supply and installation
What will a wraparound extension cost?
Guide prices for wraparound extensions, including VAT where it applies. Your fixed price is confirmed in writing after the survey.
| Wraparound extensions | Guide price incl. VAT |
|---|---|
| Standard specification | £3,400 to £3,800 per m² |
| Good specification | £3,800 to £4,250 per m² |
| High specification | £4,250 to £4,700 per m² |
Do you need permission for a wraparound extension in Harpenden?
Projects in England go through two separate checks. Planning (or confirmation that the work is permitted development) comes from the district, borough or unitary council, and building regulations approval comes from the council’s building control team or a registered building control approver. Where work touches a shared wall or digs near a neighbour’s foundations, the Party Wall etc. Act 1996 applies.
In England a wraparound extension is treated as one extension, and because it covers both the side and the rear it does not normally fit within permitted development.
What can affect a wraparound extension?
- Both neighbours may need party wall notices.
- Roof water from an L-shape needs careful falls and outlets.
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.
- Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- 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 wraparound extension cost?
Typically £3,400 to £4,700 per square metre including VAT. Many come in between £85,000 and £120,000 before the kitchen.
How long does a wraparound take?
Around 12 to 18 weeks on site after approvals.
Who deals with the council for a project in Harpenden?
We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.
Wraparound extensions in nearby towns
- Wraparound extensions in St Albans
- Wraparound extensions in Luton
- Wraparound extensions in Hemel Hempstead
- Wraparound extensions in Welwyn Garden City
Learn more about wraparound extensions, or see every project we cover in Harpenden.

