Covering Watford
Watford is about 7 miles south of St Albans. We also cover Bushey (2 miles to the south-east), Rickmansworth and Borehamwood.
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 included in a single-storey extension in Watford?
A single-storey extension adds one level of new floor space to the back or side of a house, usually to open up a kitchen, dining or family room. It is the most common way to gain space without moving, and many can be built without a planning application.
- Planning or lawful development certificate where needed
- Building control application and inspections
- Foundations, drainage and structural steel
What is the guide price for a single-storey extension in Watford?
Use these ranges to budget for single-storey extensions; the survey turns them into a fixed price for the agreed specification.
| Single-storey extensions | Guide price incl. VAT |
|---|---|
| Standard specification | £2,600 to £3,000 per m² |
| Good specification | £3,000 to £3,500 per m² |
| High specification | £3,500 to £4,000 per m² |
What approvals does a single-storey extension need in England?
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.
What should Watford homeowners check first?
- Large glazed areas need to meet energy rules, which can shape the size of doors and rooflights.
- Kitchens and doors have long lead times, so we order them early.
How does the project run?
- Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
- 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 single-storey extension cost?
Most single-storey extensions cost about £2,600 to £4,000 per square metre including VAT, depending on specification, glazing and ground conditions. We give a fixed price in writing for the agreed specification after the survey.
How long does a single-storey extension take to build?
The build itself usually takes 10 to 16 weeks once work starts on site. Design, approvals and ordering usually add 6 to 12 weeks before that.
Do you work in Watford?
Yes. Watford is within our coverage for single-storey extensions, along with nearby Bushey and Rickmansworth.
Single-storey extensions in nearby towns
- Single-storey extensions in Bushey
- Single-storey extensions in Rickmansworth
- Single-storey extensions in Borehamwood
- Single-storey extensions in Ruislip
Learn more about single-storey extensions, or see every project we cover in Watford.

