Building regulations for extensions in New Malden
For New Malden homeowners we handle building regulations for extensions, with fees agreed in writing before any work starts.
- Guide price in New MaldenFrom £1,150 inc VAT
- Approval routeFull plans or building notice
- Timescale2–5 weeks for drawings
- Postcode districtsKT1, KT2, KT3, KT4, KT5
Do I need planning permission in New Malden?
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.
The planning position for a specific New Malden address depends on its history and any designations, which is why we check it at the first visit.
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.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
What it costs in New Malden
Guide fees for New Malden including VAT, using our London factor of ×1.3. Council and building control charges are not included.
| Option | What it covers | Guide price |
|---|---|---|
| Essential | Building regulations drawings for a simple single-storey extension | £1,150 – £2,350 |
| Standard | Drawings plus structural calculations | £1,650 – £3,400 |
| Premium | Complex or two-storey pack with energy calculations | £2,850 – £4,950 |
Our design fee only. Building control charges are set by your council (or, in England and Wales, a registered building control approver) and quoted separately.
Want a range for your exact size? The guide-price tool takes about a minute.
What we take care of
- Building regulations drawings and written specification
- Structural calculations for beams, lintels and foundations
- Completion certificate on sign-off
- Inspection bookings throughout the build
- Submission to the council or a registered building control approver
- Energy and glazing checks, including whole-house calculations if needed
Building regulations approval and planning permission are separate. A design can have planning consent and still need changes to meet the regulations, which is why we draw for both together.
Covering New Malden
Our survey diary covers New Malden, including KT1, KT2, KT3, KT4, KT5, SW20. Nearby, we also take on projects in Worcester Park (2 miles), Surbiton (2 miles), Morden (3 miles), Wimbledon (3 miles).
Just over the Surrey border, Ewell is about 4 miles away. In London, space is at a premium and gardens are often short, so side returns, wraparounds and carefully planned rear extensions tend to make the most of every metre.
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
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
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Common questions in New Malden
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for New Malden, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Who do I contract with in New Malden?
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.
How long does this take for a New Malden home?
2–5 weeks for drawings, depending on the council and the complexity of the project.
What are the insulation standards for an extension?
In England, new walls in an extension should achieve a U-value of 0.18 W/m²K, roofs 0.15 and floors 0.18, with windows at 1.4 and rooflights at 2.2. Wales, Scotland and Northern Ireland set their own figures.
Full plans or building notice?
A full plans application gets the drawings checked before work starts, which we usually recommend for extensions. A building notice is quicker to submit but carries more risk if something needs changing on site.
Book a free site visit in New Malden
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.