[2023] UKUT 00282 (LC)

The evidence of the surveyors and the engineers enables us to make the following findings.

We find, in line with the claimants’ unchallenged evidence and the agreed evidence of the surveyors, that since the works were undertaken by the respondent there has been some deterioration to the house in terms of increased dampness in the ground floor walls, additional cracking to internal finishes, and movement outwards of the wall in the south-east face of the house leaving a gap between the wall and the stringer to the staircase. We also find that the pre-existing cracking and movement at the property was not significant, and that the movements observed between 2014 and 2022 are not structurally significant at the moment, with the possible exception of that on the south-east face. We note that the signs of deterioration have increased since initial post-works inspections in 2016, which would be consistent with a problem growing over time.

We find, in line with the engineers’ agreed evidence, that although there were vibrations caused by construction of the works, vibrations have not damaged the house.

We find, in accordance both with the agreement of the surveyors about causation and with the more detailed agreement of the engineers, that if groundwater levels have risen as a result of the respondent’s work then on the balance of probabilities the deterioration to the house has been caused by the effect of that groundwater on the foundations and structure of the house, and that more damage will be caused in the future. We make no separate finding about the allegation of damage to the pool and we have not set out the evidence about it, which is ambiguous; we find that if the house has been damaged by the works then it is probable that the pool has been too.

If groundwater levels have not risen then the claimants’ case on causation fails because there is nothing then to indicate how the observed changes to the fabric of the house could have been caused by the respondent.

Accordingly, our decision on the preliminary issue turns on the evidence of the expert witnesses on hydrology.