Timber frame extensions across Borehamwood
We design and build timber frame extensions for houses in Borehamwood, with a written price once the survey and design are done and one point of contact throughout.
- Guide price in BorehamwoodFrom £22,000 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time8–14 weeks on site
- Postcode districtsWD6, WD7

What should I budget for a timber frame extension in Borehamwood?
These guide figures apply our East of England adjustment (×1.06) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Borehamwood: £1,860 to £3,600 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £22,000 – £27,000 | £26,000 – £34,000 | £33,000 – £43,500 |
| 4 m × 5 m 20 m² | £37,000 – £45,000 | £43,000 – £56,500 | £55,000 – £72,500 |
| 5 m × 6 m 30 m² | £55,500 – £67,000 | £65,000 – £84,500 | £82,500 – £108,500 |
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 rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
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 regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Applications are decided by the local planning authority (your district, borough or unitary council).
What is included
- Cladding, render or brick slip finish
- Fire and acoustic details where needed
- Breathable wall build-up with insulation
- Frame design and structural calculations
- Foundations, often lighter than masonry
Moisture is the enemy of any timber building. We design ventilated cladding cavities, breather membranes and a proper damp-proof course height, and keep the frame dry during construction.
Working in Borehamwood
We cover Borehamwood and the postcode districts WD6, WD7. Nearby, we also take on projects in Bushey (4 miles), Potters Bar (5 miles), Watford (5 miles), St Albans (7 miles).
For homes towards Greater London, Barnet is around 3 miles away. 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.
What happens next
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
We visit your Borehamwood home, measure up, talk through what you want and check the planning position.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Questions people ask about timber frame extensions
How long does a timber frame extension take to build in Borehamwood?
On site, typically 8 to 14 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
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.
Who do I contract with for a timber frame extension in Borehamwood?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Does a timber frame extension need planning permission?
The same planning rules apply as for any extension. If the cladding looks different from the house, permitted development’s matching-materials condition may mean an application is needed.
Is timber frame cheaper than brick?
It is similar overall. The frame can save time on site, but the cladding choice has a big effect on cost. Our guide range is about £1,860 to £3,600 per m² including VAT.
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.