Watford, Hertfordshire
Terraced house rear extension in Watford
Rear and side return extensions for terraces, with access through the house and two neighbours. We design, get the approvals for and build rear extensions for terraced houses in Watford and the surrounding area, with one contract from the first survey to building control sign-off.
Watford and its postcode districts WD1, WD17, WD18 and WD24 are part of our Hertfordshire coverage. On a Watford terrace both neighbours usually need party wall notices or agreement, so we talk to them early.
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 terraced house rear extension cost in Watford?
For Watford we work from the East of England rate: £2,170–£3,500 per square metre of new floor, including VAT, standard specification. 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 |
|---|---|
| 3 m wide × 4.5 m deep (13.5 m²) | £29,500–£47,000 |
| 3 m wide × 6 m deep (18 m²) | £39,000–£63,000 |
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 terraced house rear extension in Watford?
Planning for a terraced house rear extension in Watford follows the English householder rules.
English permitted development (Class A) allows a single-storey rear extension of 3 metres on a terraced or semi-detached house and 4 metres on a detached one, measured from the original house, with a maximum height of 4 metres and eaves of no more than 3 metres within 2 metres of a boundary.
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. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Watford like to extend?
Post-war semis and newer estates are typical of Watford, and many have room for a full-width extension. Shrinkable clay is common in the East of England, so foundations near trees and hedges are designed to NHBC-style depth guidance.
How a terraced house rear extension in Watford comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
Written price, then build
Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.
Terraced house rear extensions near Watford
Neighbouring places we cover include West Watford (0.9 miles) and Bushey (1.7 miles).
- Terraced house rear extension in West Watford
- Terraced house rear extension in Bushey
- Terraced house rear extension in North Watford
- Terraced house rear extension in Croxley Green
- Terraced house rear extension in Northwood
Other work in Watford:
FAQ
Terraced house rear extension questions in Watford
What postcode areas do you cover around Watford?
Including WD1, WD17, WD18, WD24 and WD25, and the surrounding Hertfordshire area.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.
Will my terrace be in a conservation area?
Many Victorian terraces are. Your council's map shows it; we check at the survey.
Do I need planning permission for a rear extension in Watford?
Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.
Do you handle building control in Watford?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
Do I need a party wall agreement?
In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.