Calculating a Loss When a Crack Widens

by: The Party Wall Surveyor


I consented to my neighbour’s works on the understanding that I should not suffer as a consequence. Many of the existing cracks have widened but my neighbour is saying because they are existing they are not his responsibility. Can this be correct?


Certain rights under the Act, such as cutting in to a party wall, come with an obligation to make good damage, while others, such as excavating close to a neighbour’s property do not. However, the building owner (the party undertaking the works) is responsible for any loss or damage caused by their works. The distinction may appear technical but it’s relevant to your query.

If a crack has widened as a result of the works it is unquestionably damage and as such the building owner has a duty to make good. Importantly, it also follows that you, as an adjoining owner, can elect to receive a payment in lieu of making good (see section 11(8) of the Act).

If there is no duty on the building owner to make good they will only be responsible for the loss suffered as a result of the works. The ‘loss’ when an existing crack widens slightly is always difficult to assess – it does not cost any more to make it good so the more relevant point is whether, as a result of the crack widening, it has become more urgent to make it good and redecorate.