- Planning authority
- Dorset Council
- Postcodes
- DT1
- Noon sun, 21 March
- About 39°
- Shadow from a 5 m eaves line
- About 6.1 m
- Planning plan
- Local Plan
- County
- Dorset
The local picture in Dorchester
Dorset Council will judge a family home against the council’s Local Plan and any guidance it has adopted on garden development and annexes. Some councils spell out how closely an annexe must relate to the main house, such as sharing the drive, garden or parking, and what turns a building into a separate home instead. We read the current policies for your address before design starts, because a scheme drawn to suit the wrong test wastes time and money. Where the position is unclear, the council’s pre-application advice can be worth its fee.
What happens next in Dorchester
Getting started in Dorchester costs nothing. Send us a few photos of your garden and the way in, or simply call, and we’ll look at the plot from the desk and talk through your family’s plans. If there’s a realistic scheme, we arrange a site visit. Survey and design are quoted in writing before you commit, and the build price follows once the design is settled.
Free plot appraisal
We look at your plot, access and the planning picture from the desk, talk through who will live in the new home, and visit if it looks viable. There’s no cost and no obligation.
Annexe or separate home
We set out both routes for your plot, covering what each means for planning, ownership, council tax, CIL and VAT, so you can decide with your family and advisers before design starts.
Survey and design
A measured survey, then a design built around the person moving in: step-free routes, a ground-floor bedroom if needed and privacy for both households. You get a written quote after design and survey.
Planning and approvals
We prepare and submit the planning application and manage it with the council, which makes the decision. Before work starts, approval under the Building Regulations is in place and any CIL exemption has been claimed.
Worth checking early
- Family plans change: agree ownership, costs and what happens if circumstances change in writing, with a solicitor.
- CIL exemptions are lost if work starts before the claim is made, and can be withdrawn if the home is sold or let within three years.
- An annexe tied by planning condition usually can’t be sold or let separately, which limits flexibility later.
Dorchester: questions to ask
Can I reclaim VAT on a family annexe in Dorchester?
Often not. HMRC’s guidance gives an annexe that can’t be used or sold separately from the main house as an example of work that can’t be zero-rated, and the DIY housebuilders refund scheme asks the same question. A separate dwelling is usually treated differently. Take advice from a tax adviser before you settle the planning route, because the wording of the permission matters.
Do I need planning permission for a granny annexe in Dorchester?
Yes, almost always for a detached annexe with its own kitchen, bathroom and bedroom. Dorset Council will treat it as accommodation linked to your home and will usually add a condition so it can’t be let or sold separately. A garden building used only as a home office or gym is a different matter, but sleeping and cooking take it beyond those allowances.
Who owns an annexe built in my Dorchester garden?
You do. An annexe stays on the title of your house and usually carries a planning condition tying it to the main home, so it can’t be transferred to the relative living in it. If a family member is paying towards it, record what they’ve put in and what happens on a sale in a written agreement drawn up by a solicitor.
Is CIL payable on a family home in Dorchester?
Only if Dorset Council has adopted the Community Infrastructure Levy, which its website will confirm, and we check it for you during the appraisal. Where it applies, self-build and residential annexe exemptions exist, but both must be claimed before work starts and can be withdrawn if the home is sold or let within three years of completion.
Other options in Dorchester
- Planning permission for a garden plot
- Build a new home in your garden
- Garden plot option agreement
- Bungalows on large plots
- Large rear gardens
- Garage courts and yards

