Neighbours damp proofing on party wall pushing water to my side

azmodan · 19 March at 11:03AM

I have an issue with damp along the length of a party wall that I share with a private HMO for students. I purchased my home in March 2020 and a couple of months later the neighbouring property was granted planning permission for conversion from a 2 bed terrace to a 3 bed HMO. The houses are approximately 1920 Edwardian builds with slate dpcs, solid lime mortared brick and rubble walls with no cavities. All properties have two chimney flues on the ground floor with recesses alcoves either side.

Some parts of the walls are very thick, in excess of 2 feet, whereas others, such as the alcoves, are single brick, 4.5 inches - the bricks in these places are shared.

A few months after the works began next door I started noticing damp patches on the wall that we share. This particular wall has the chimney flues and alcoves on the neighbours side, mine is flat.
The patches grew, so I knocked the door and asked the workmen if there was any damp next door. They told me no.

Since then the damp in my side got progressively worse to the point where paint and lime plaster started disintegrating and delaminating from the wall. The bricks underneath were wet to the touch, including many that both properties share.

I had a damp survey carried out with identified some problems with my home such as high exterior ground levels where the patio had been built up. It was also found that the downpipe from the roof in the neighbours property was blocked and damaged, chanelling rain water fromt he roofs directly into the ground adjacent to the foundations. The council served an enforcement notice on the neighbours landlord to make repairs, which he had to carry out 3 times due to poor workmanship and cutting corners.

That was a couple of years ago, but the damp hasn't stopped.

As part of treatment for my own home I was advised to repoint the shared wall due to the state of the mortar. Some of the bricks were loose and had to be removed, cleaned up and reseated with fresh materials. This is work I've been carrying out over the last few months.

The landlord has maintained for years via his letting agent that there was no problem with his side. I got the council involved, and they confirmed my side was wet, but couldn't find any damage on his side so were unable to help further.

However, the repointing work revealed the state of the other side of the wall, and what improvements had been made since it was converted. The landlord has applied a thick layer of cement along the length of the party wall. The alcoves have been sealed up completely with studwalls and a vertical DPC has been placed along the entire length of the wall from front to back. The alcoves have damp on the floor and mould on the walls.

This second source of the water is from a retaining wall in the rear of his property that has been blocked with an extension, works that were carried out long before either of us were owners. The patio next to this, which also comes into contact with my kitchen wall (not shared, on the boundary) is the same height as the interior floors of next doors property. Rainwater that falls in the neighbours garden is draining into the soil, hitting the retaining wall, and then following the path of least resistance which takes it under the patio. From there it cannot evaporate and the only place for it to go is into foundations. Heavy clay soils around both homes prevent water from draining, so the only way to deal with it is to direct it to the sewer system.

There is no doubt in my mind that the neighbour has tried to deal with the damp by hiding the symptoms instead of treating the cause, but the council are not prepared to touch it, citing common enemy defense. They will only involve themselves if the tennants complain, which they have no reason to because the damp is all on my side of the DPC hes put up along the wall. The landlord still refuses to speak with me and the agency are not interested.

I know I need to take civil action but quotes from solicitors in the event of it going to court are in excess of ten thousand pounds, money which I simply do not have access to. I earn just enough to exclude me from legal aid, but not enough to save that sort of money in a reasonable time frame.

I will have to bring the case to court myself, but I'm not sure which building regulations/laws would be most appropriate to lean on.

Any advice would be greatly appreciated.

Thank you