A survey on a house for sale will identify any issues for the potential buyer. The most common problems identified, according to the Royal Institution of Chartered Surveyor’s (RICS), are subsidence or structural movement, damp, rotten timber, dry or wet, defective wiring, roofs or heating systems that need replacing. Issues such as wiring, damp, roof coverings and heating systems can be overcome with advice, and quotes on the work, from the relevant trades. These costs can become part of the negotiation between buyer and seller, but where subsidence or movement is concerned this can be indicative of more serious issues and requires a structural engineer to assess the problem. We receive calls regularly to inspect ominous cracks, be it in a wall or where the floor has come away from the walls. Both are indications of movement issues and are often identified as the result of a survey.

At this point buyers may walk away from the sale, for fear there is something fundamentally wrong with the house or wait and find out the outcome of our report. This report provides objective advice about the condition of the property, so buyers can proceed, if they wish, with all the facts and possibly revise their offer on the house. Regardless of the buyer’s decision, a bad survey leaves the seller in the stressful position of needing to find out the severity of the issue and how much it will cost to remedy it. However, it is not always bad news; cracks in ceilings and walls can be the result of cyclical movement and may be nothing to worry about.

Stepped diagonal cracks in walls are another matter and indicate something is moving. Structural Engineers will assess the cause of movement. The usual suspects are trees, collapsed drain runs or chalk soil that has been eroded over time. Until 2007 the minimum requirement for foundations was a depth of 0.75 meters. Houses built with these shallow foundations near trees may find that growing trees have desiccated the soil causing movement or that the removal of a large tree has rehydrated the ground causing it to rise. Ideally, foundations near trees should be designed in accordance with the National House Building Council (NHBC) standards to ensure the moisture content of the clay is significantly below what it would naturally be and is not affected by nearby trees.

If you’re buying or selling a house that is less than 10 years old, check if it is under any kind of warranty supplied by providers such as NHBC, Construction Insurance Specialist; CRL, or Premier Guarantee. If so they will be able to investigate any major concerns flagged up in the survey.

Another way to avoid investigative costs stemming from a bad report is to have the ‘as built’ records. Since 1997 CDM regulations have required ‘as built’ drawings to be completed. These are an accurate record of what has actually been built. They will show the foundation depths, any assumptions made in the design and can help to form the basis of any investigation, cutting down costs with no need to dig numerous trenches or rip up floors. Most people don’t realise these drawings exist or that there will also be an O&M manual (Operations and Maintenance) that will have been given to the client on completion. Both these documents are something all buyers should be asking to see when purchasing a house.

A poor survey doesn’t have to mean the end of a sale, but getting structural engineering advice is vital for any cracks or concerns about the structure of a building to find out the severity and ways to repair the problem for a successful sale in the future.