Party walls and boundaries
If the seller had planning permission, can you ignore the Party Wall etc. Act?
No. GOV.UK says agreeing under the Act does not remove the need for planning permission or building regulations, and planning permission or building regulations do not remove the need to comply with the Act. A home survey does not check that any of the three was done. Your solicitor asks for the papers. The survey describes the building.
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?
An extension can have planning drawings and still have been built without notice to the neighbour. The drawings do not prove notice. The neighbour’s later complaint is not a crack, and a crack is not a complaint. Keep them separate when you decide whether to renegotiate.
If papers are missing, the seller’s indemnity policy, if one is offered, is a legal product your solicitor explains. It is not a structural repair and not a condition rating. The surveyor should not be asked to bless the policy. No premium is stated here.
What should you ask your surveyor?
- Which papers did you see: planning, building regulations, a party-wall award, or none?
- Are there cracks at the junction with the extension?
- Are you being asked to say the work was lawful? You should not be.
What are the typical next steps?
- Give the solicitor the list of missing papers without turning it into a defect list.
- Give a builder the crack, if there is one, without turning it into a legal opinion.
- Do not pay twice, once for indemnity and once for a rebuild, without understanding what each is for.
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 certificate of lawfulness replace the Act?
It addresses planning status. It is not a party-wall award. Ask the solicitor what the certificate actually says.
Is building-regulations approval the same as planning?
No. GOV.UK treats them as separate, and the survey as neither.