What is a wraparound extension?

A wraparound extension combines a side return and a rear extension into one L-shaped addition. It gives the largest possible ground floor, often creating an open-plan kitchen, dining and living space across the whole width of the house.
How much does a wraparound extension cost in Hertford?
In Hertford, a wraparound extension typically costs £2,350–£3,400 per m² of floor area, including VAT at 20% (standard rate). For a typical 28 m² project that is roughly £66,000–£95,000. Building costs in the East of England run about 6% above the UK average, and the figures for Hertford are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (20 m²) | £47,000–£68,000 |
| Typical project (28 m²) | £66,000–£95,000 |
| Larger project (39 m²) | £91,500–£132,500 |
| Rate per m² | £2,350–£3,400 |
Your quote will depend mainly on:
- Total footprint and the amount of glazing
- Kitchen and flooring specification
- Drainage changes
- Access for materials on terraced streets
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a wraparound extension in Hertford?
Approvals for a wraparound extension in Hertford follow the rules for England. In England a wraparound extension combines side and rear elements, which normally takes it outside permitted development, so a householder planning application is made.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
We check this for your address before design work starts, so there are no surprises later.
What we handle
Handled as part of most wraparound extensions:
- Structural engineer’s design for steels and supports
- Party wall notices and surveyor liaison
- Foundations and drainage
- Removal of internal and external walls
- Walls, roof and glazing
- Design and planning application
How long does it take?
Allow 12 to 18 weeks on site. Design and approvals come first and typically take 3 to 4 months, depending on the approval route.
Building in Hertford
Many towns in the East of England have estates built since the 1970s, where garage conversions and rear extensions are popular.
We work across Hertford and neighbouring areas such as Hoddesdon, Welwyn Garden City and Hatfield. Postcodes we cover in Hertford include SG13.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about wraparound extensions in Hertford
How much does a wraparound extension cost in Hertford?
In Hertford, a wraparound extension typically costs £2,350–£3,400 per m² of floor area, including VAT at 20% (standard rate). A typical 28 m² project comes to roughly £66,000–£95,000. Your fixed price depends on the survey and drawings.
Can we keep a separate living room?
Yes. Many clients keep the front room separate and open up only the back of the house.
Will both neighbours be affected?
Usually only the neighbour on the side return side, but rear foundations near either boundary can trigger party wall notices.
How long does a wraparound extension take in Hertford?
Typically 12 to 18 weeks on site. Design and approvals beforehand usually take 3 to 4 months.
Is a wraparound worth it?
It gives the biggest ground-floor space without going upwards. Whether it adds value depends on your street and house, so we suggest checking local sale prices before committing.
