Outbuildings and conservatories
Does an annex with its own consumer unit count as a separate dwelling in the survey?
No. A second consumer unit means there is a distribution board in the annex, and the survey did not test it or decide that the annex is a separate dwelling. Use, planning and the title are questions for your solicitor. The survey can describe the parts of the annex it entered, and nothing more legal than that.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
Annexes are sold as granny flats on the strength of a kettle and a board. The electrical point is the same as anywhere else: a visual note is not a test, and fittings are not removed on a standard inspection. The Level 1 scope leaves electrics untested. If the board was locked in a cupboard, it was not even seen. Say so. Do not borrow the house’s electrical comments for the annex.
Whether you can live in it, let it or sell it later is not a condition rating. Approval and the planning status are outside this inspection. There is no box on the survey that creates a dwelling. If the annex was not entered, it is not inspected. A consumer unit you glimpsed through a window is a glimpse, not a certificate and not a council decision.
What should you ask your surveyor?
- Did you see the annex board, and did you leave it untested?
- Which rooms of the annex were entered?
- Are you calling the annex a separate dwelling?
What are the typical next steps?
- Use an electrician if you need the annex circuits tested.
- Use the solicitor if you need to know whether it is a separate dwelling.
- Do not add the annex as a bedroom in your plans solely because it has a consumer unit.
Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.
Also asked about this
Does a kitchenette decide the question?
No. Fittings show how it is used. They do not create a lawful separate dwelling in the survey.
Is the annex board covered by a test of the house?
No. A test, if you later commission one, has to include the board it claims to cover. The home survey did not do that test.