Can I Sell a House Quickly With Unapproved Alterations?

What "unapproved alterations" means

Unapproved alterations are changes to a property — extensions, conversions, structural work, new windows — done without the required planning permission (whether the work was allowed) and/or building-regulations approval (how it was built). The first step is to identify which consent is missing, as that determines the fix. This is the same issue as an unauthorised extension or missing building regulations.

The options

Regularise or insure

Regularising means applying to the council for retrospective planning permission (or a lawful development certificate) and/or a building-regulations regularisation certificate — giving the cleanest title and widest market, but taking time. Indemnity insurance suits older work where enforcement time limits have largely passed, protecting the buyer and lender so a mortgage sale can proceed. As always, do not contact the council about the specific work once you intend to insure, as that can void the policy.

Disclosure

You must disclose unapproved alterations on the property information form — the buyer’s solicitor checks planning and building-control records, so concealment is futile and risks a misrepresentation claim. Provide whatever you have: the date of the work, any partial consents, and any indemnity policy. Honest disclosure with a clear plan (regularisation or insurance) keeps the sale moving (see disclosure duties).

Selling fast

If regularising is slow, the work is deterring mortgage buyers, or you need speed, a cash buyer or investor will purchase with the issue disclosed, accept or insure the risk, and complete in 7-28 days without a lender to satisfy. Cash buyers handle unapproved work routinely. See illegal extensions.