Building regulations for extensions across Dorchester
Need building regulations for extensions in Dorchester? We survey the house, prepare what the council needs and deal with the officers until a decision is made.
- Guide price in DorchesterFrom £900 inc VAT
- Approval routeFull plans or building notice
- Timescale2–5 weeks for drawings
- Postcode districtsDT1
Local to Dorchester
Across DT1, we can visit, measure and advise. The same team covers Weymouth (7 miles), Bridport (15 miles), Poole (20 miles), Wimborne Minster (22 miles), all within easy reach.
Yeovil, in Somerset, is roughly 18 miles from Dorchester and also on our list. In the South West, local stone, render and brick vary from town to town, so matching materials is a big part of designing an extension that looks right.
Fees in Dorchester
These are guide fees for Dorchester, adjusted for South West England (×1.02) 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 | £900 – £1,850 |
| Standard | Drawings plus structural calculations | £1,300 – £2,700 |
| Premium | Complex or two-storey pack with energy calculations | £2,200 – £3,900 |
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.
For a figure based on your own dimensions, use our guide-price tool.
Included in a typical project
- Building regulations drawings and written specification
- Completion certificate on sign-off
- Inspection bookings throughout the build
- Energy and glazing checks, including whole-house calculations if needed
Do I need planning permission in Dorchester?
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 Dorchester 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.
Applications are decided by the local planning authority (your district, borough or unitary council).
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
We visit your Dorchester 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
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Questions answered
Who do I contract with in Dorchester?
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.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Dorchester, 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 I need building regulations approval in Dorchester?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Who are building control?
Either your local council’s building control team or a registered building control approver. Both inspect the work and issue the completion certificate.
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 Dorchester
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.