Building regulations for extensions in Potters Bar
For Potters Bar homeowners we handle building regulations for extensions, with fees agreed in writing before any work starts.
- Guide price in Potters BarFrom £950 inc VAT
- Approval routeFull plans or building notice
- Timescale2–5 weeks for drawings
- Postcode districtsEN6

Design and approval fees for Potters Bar
These are guide fees for Potters Bar, adjusted for East of England (×1.06) and including VAT. Council application and inspection fees are paid separately.
| Option | What it covers | Guide price |
|---|---|---|
| Essential | Building regulations drawings for a simple single-storey extension | £950 – £1,950 |
| Standard | Drawings plus structural calculations | £1,350 – £2,800 |
| Premium | Complex or two-storey pack with energy calculations | £2,300 – £4,050 |
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.
Try the guide-price tool to see a range for your own size and finish.
When it helps
- Homeowners using their own builder who need the drawings
- Glass-heavy designs that need energy calculations
- Every extension, whatever the planning route
Planning rules that apply in Potters Bar
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 Potters Bar address depends on its history and any designations, which is why we check it at the first visit.
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.
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).
Working in Potters Bar
Postcode districts we cover around Potters Bar include EN6. The same team covers Borehamwood (5 miles), Hatfield (5 miles), Cheshunt (6 miles), Welwyn Garden City (8 miles), all within easy reach.
Barnet, in Greater London, is roughly 3 miles from Potters Bar and also on our list. Across the East of England many houses sit on generous plots, and single-storey and wraparound extensions are a natural fit.
How the project works
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
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Questions answered
Do I need building regulations approval in Potters Bar?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
How long does this take for a Potters Bar home?
2–5 weeks for drawings, depending on the council and the complexity of the project.
Who do I contract with in Potters Bar?
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.
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.
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.
Book a free site visit in Potters Bar
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.