One of the most common reasons a property transaction fails in 2026 is the discovery of an unauthorised extension, loft conversion or internal structural alteration.
At Howorth, we specialise in Licences for Alterations and Party Wall matters, meaning we have a “sixth sense” for identifying work that hasn’t been done by the book.
The “Silent” Risks of DIY Structural Work
Many homeowners assume that because an extension has been standing for ten years, it is “safe”. This is a dangerous fallacy. Structural failure can be slow, and the lack of a completion certificate from the local authority is a massive red flag.
What We Investigate During the Survey
1. Structural support and load-bearing walls: We frequently find that when a wall is removed to create an open-plan living space, the steel beam (RSJ) used is either undersized or incorrectly supported, sometimes by crushing the brickwork. We look for cracks in the plaster above these openings and bounce in the floors above, which can indicate structural deflection.
2. Loft conversions: bedrooms vs storage: A loft cannot legally be described as a bedroom unless it meets strict Building Regulations regarding fire escape routes, floor joist strength and head height. If we find a DIY loft conversion being marketed as a principal suite, we will flag it. Not only can it be a fire trap, but it may also lead to your lender withdrawing their mortgage offer once they review our report.
3. Party Wall and boundary issues: As specialists in the Party Wall etc. Act 1996, we check whether the extension has been built correctly in relation to the neighbour’s land. If the previous owner built over the boundary or failed to serve the correct notices, you could be inheriting a legal battle. At Howorth, we ensure you are protected from these unforeseen liabilities.
The Walk-Away Point
If an extension is structurally unsound and lacks the necessary legal paperwork, the cost to regularise it often exceeds the value it adds.
Unless the seller reduces the price significantly to cover both the structural remedial works and the legal costs of obtaining retrospective consent, we advise walking away.
Our passion is protecting your investment — and that means being firm when a “dream home” is actually a legal nightmare.