Age and type of house
The extension is in Wales. Why is an English approved document the wrong rule to treat as the Welsh building regulation?
Because this extension is in Wales, and an English approved document is not the Welsh building regulation. Each nation publishes its own guidance, and a familiar-looking extension does not make the English text the rule on this plot. An English approved document guides work in England. Treating it as the standard for a Welsh extension uses the wrong document. The survey can describe what it saw. It does not decide whether Welsh building regulations were met, and it does not issue a building-regulations certificate.
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?
It is easy to search an English approved document because structure or drainage sounds the same either side of the border. That search can pull in the wrong edition and the wrong amendments. The survey does not decide which national document applied when the extension was built. It records the building. Whether the work was signed off is a paperwork question, and if needed a building-control question. Quoting an English paragraph at a Welsh wall does not answer it.
Ask the solicitor for any Welsh completion certificate, building notice or plans approval, and for the date of the work. Those papers show what was applied for, if anything was. Do not put an English approved document into the legal pack as though it were the consent. A lender may ask whether regulations were signed off. The accurate reply from this report is that the survey has not decided, and has not used an English document as the Welsh rule.
What should you ask your surveyor?
- Which Welsh certificate, if any, is actually in the pack?
- What date is given for the extension, and does any approval match that date?
- Does the report stay with condition, rather than giving a regulations verdict?
What are the typical next steps?
- Stop treating an English approved document as the rule for this Welsh extension.
- Ask the solicitor to look for the Welsh building-control completion paper.
- Tell a lender the survey described the extension and did not certify compliance.
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
If the extension looks like one in England, can the same document still be used?
Looks do not choose the legal text. A similar beam or opening can exist under either regime while the approval route remains Welsh. The survey has not compared the documents clause by clause. When someone asks which rules were in play, use the Welsh papers, not a resemblance to an English example.
Has the survey failed the extension by refusing the English document?
No. Refusing the wrong document is not a condemnation of the extension. The survey records condition. It has not said the work is unlawful and it has not said it complies. Those conclusions need the Welsh building-control record. This visit did not issue that record and does not replace it.