Side return extensions in Borehamwood: design, approvals and build
Our design and build teams take on side return extensions in Borehamwood, from the first measured survey through planning and building control to the finished room.
- Guide price in BorehamwoodFrom £19,000 inc VAT
- PlanningOften permitted development; party wall notice usual
- Build time10–14 weeks on site
- Postcode districtsWD6, WD7
When a side return extension makes sense
- Narrow galley kitchens
- Homes where the garden is too small to lose much depth
- Victorian and Edwardian terraces with a rear outrigger
Light is the design problem. A side return can make the middle of the house darker if the roof is solid, so we model the daylight and usually recommend a glazed slope or a run of rooflights along the boundary edge.
What should I budget for a side return extension in Borehamwood?
For Borehamwood we adjust our national guide rates by ×1.06, the factor we use for East of England. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Borehamwood: £2,230 to £4,030 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 1.8 m × 4.5 m 8 m² | £19,000 – £23,000 | £20,000 – £25,500 | £25,000 – £32,500 |
| 2 m × 5.5 m 11 m² | £24,000 – £29,500 | £27,500 – £35,000 | £34,500 – £44,500 |
| 2.2 m × 7 m 15 m² | £33,000 – £40,000 | £38,000 – £48,000 | £47,500 – £60,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
Do I need planning permission in Borehamwood?
In England a single-storey side return infill is often permitted development if it stays within the height limits and is no wider than half the width of the original house. Conservation areas, listed buildings and flats always need an application, and the boundary wall usually brings in the Party Wall Act.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
Applications are decided by the local planning authority (your district, borough or unitary council).
Covering Borehamwood
Postcode districts we cover around Borehamwood include WD6, WD7. We also work in nearby Bushey (4 miles), Potters Bar (5 miles), Watford (5 miles), St Albans (7 miles).
The East of England mixes market-town terraces, inter-war semis and modern estates. Clay soils are common in parts of the region, which can affect foundation design.
Our process, step by step
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Side return extension questions answered
Do I need building regulations approval in Borehamwood?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Borehamwood, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do you cover all of Borehamwood?
Yes. We cover Borehamwood and the surrounding parts of Hertfordshire. Site visits are free and there is no obligation.
Will the kitchen be darker?
Not if the roof is designed well. A glazed roof or a line of rooflights along the boundary usually makes the room brighter than before.
Do side return extensions need planning permission?
In England many single-storey side returns fit within permitted development if they stay within the height limits and are no wider than half the width of the original house. Conservation areas, listed buildings and flats need an application. Other UK nations have their own rules, which we check.
Book a free site visit in Borehamwood
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.