Extension plans and drawings in Dorset
We prepare extension plans and drawings for homes across Dorset, on their own or as the first stage of a full design and build project.
- Guide priceFrom £1,200 inc VAT
- PlanningWe find the right route for you
- Towns covered9
- Site visitFree, no obligation
Towns in Dorset
Working in Dorset
Towns we cover in Dorset include Bournemouth, Poole, Weymouth, Christchurch, Dorchester, Wimborne Minster, Bridport, Ferndown. 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.
Included in a typical project
- Two or three layout options to compare
- Structural calculations from an engineer (full pack)
- 3D views to check the look and the light (full pack)
- Building regulations drawings and specification
- Measured survey of the house and garden
Planning rules that apply in Dorset
In England the main routes are permitted development (ideally confirmed with a lawful development certificate, £274), larger home extension prior approval (£249, 42 days) and a householder planning application (£548, normally 8 weeks), with council fees as set from 1 April 2026.
The planning position for a specific Dorset 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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Design and approval fees for Dorset
Fees below are our Dorset guide (×1.02, the South West England factor), including VAT. Council and building control fees are extra.
| Option | What it covers | Guide price |
|---|---|---|
| Essential | Measured survey and planning drawings | £1,200 – £2,250 |
| Standard | Planning drawings plus building regulations drawings | £2,200 – £3,900 |
| Premium | Full pack with structural calculations and 3D visuals | £3,450 – £5,650 |
Want a range for your exact size? The guide-price tool takes about a minute.
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
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Common questions in Dorset
Will my neighbours in Dorset be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
How long does this take for a Dorset home?
2–6 weeks for drawings, depending on the council and the complexity of the project.
Do you cover all of Dorset?
Yes, across the whole of Dorset. Site visits are free and there is no obligation.
Can I use your drawings with another builder?
Yes. Once paid for, the drawings are yours to use for your project.
Do I need an architect?
Not necessarily. For most extensions an experienced designer or architectural technologist is enough. For listed buildings or complex sites an architect’s input can help.
Book a free site visit in Dorset
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.