Harpenden, Hertfordshire
Wraparound extension in Harpenden
For homes in Harpenden, a wraparound extension is often the simplest way to gain space without moving. An L-shaped extension that fills the side return and runs across the back. We take it from survey to completion certificate.
Harpenden and its postcode districts AL5 are part of our Hertfordshire coverage. Wraparounds are the natural next step for the end-of-terrace and Victorian houses in Hertfordshire where a side return alone would leave the room too narrow.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a wraparound extension cost in Harpenden?
Guide prices for a wraparound extension in Harpenden start from our East of England rate of £2,330–£3,820 per square metre, including VAT. East of England prices run slightly above our West Midlands baseline; clay soils near trees are the main foundation variable.
| Size | Guide price inc VAT |
|---|---|
| L-shaped, about 22 m² of new floor | £51,500–£84,000 |
| L-shaped, about 30 m² of new floor | £70,000–£114,500 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission for a wraparound extension in Harpenden?
Here is how the rules in England apply to a wraparound extension in Harpenden.
In England the side part of a side return or wraparound must meet the side-extension rules (one storey, under 4 metres high, no more than half the width of the original house), and those rights do not apply on designated land. Because a wraparound combines a side and a rear extension, many need householder planning permission.
Because rear extensions often sit on or near the boundary, the Party Wall etc. Act 1996 usually applies in England. Notices go out one or two months before work depending on the type of work, and a surveyor's award is only needed if a neighbour does not consent.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.
What are homes in Harpenden like to extend?
Harpenden mixes Victorian terraces with 1930s semis, so both side returns and full-width kitchen extensions suit houses here.
How a wraparound extension in Harpenden comes together
Look round and measure
A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Wraparound extensions near Harpenden
Close by, we work in St Albans, about 4.7 miles away, and Luton, about 5.0 miles away.
- Wraparound extension in St Albans
- Wraparound extension in Luton
- Wraparound extension in Codicote
- Wraparound extension in Hemel Hempstead
- Wraparound extension in Welwyn Garden City
Other work in Harpenden:
FAQ
Wraparound extension questions in Harpenden
What postcode areas do you cover around Harpenden?
Including AL5, and the surrounding Hertfordshire area.
How much does a wraparound extension cost in Harpenden?
As a guide, £2,330–£3,820 per square metre including VAT for a standard specification. For example, L-shaped, about 22 m² of new floor: about £51,500–£84,000 at that rate. Your written price follows the survey.
Will it take a lot of garden?
Less than a deep rear extension of the same area, because part of the space comes from the side passage.
How long does a rear extension take to build in Harpenden?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
Do you handle building control in Harpenden?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.