Is My Neighbour’s Work Notifiable Under The Act?

Question

My neighbour has planning permission for a double storey side extension. I am concerned about the extension for various reasons including movement that might be caused underneath my property by the work. We live off a busy main road and get lots of vibration from the traffic, especially when heavy lorries go past. I believe the vibration comes through as our property is approximately 3-4 metres lower than the main road itself. I am concerned that the digging of foundations for the extension may cause considerably worse problems than we get from the main road given the proximity of the drilling. 

Currently the side of my property is approx 3.6m from the boundary and my neighbours is approx 4.9m from the boundary. According to the plans once the work is done my neighbours property will only be approx 1.17 from the booundary, a total of 4.77m away from my property. I believe because this is less than 6m I have some rights pertaining to the Party Wall Agreement that may prevent the works from taking place. Please could you confirm whether any of the above relates to the Party Wall Agreement. 

I am also unclear whether my neighbour is required to give me notice of the commencement of the works.

Answer

As your neighbour’s excavation work is more than 3 metres away from your structure it could only be the 6 metre notice that would apply but the excavations would have to be quite deep for that to be the case. The test is whether any part of the proposed excavation intersects with a plane drawn downwards at an angle of 45 degrees from the bottom of your foundations, taken at a line level with the face of your external wall. Over the distance that you mention this would mean that their foundations would have to be at least 4 metres deep to be notifiable under the Party Wall Act – that would probably only be the case if they were using piled foundations.

Follow-up

Many thanks for your response. How deep are foundations normally? My neighbours house was built around 1900 and mine was built in 1975. 

Do they have to give me notice prior to the works starting?

Answer

The foundations to a 1900 house are likely to be brick corbels – no more than 500 – 600mm deep. By 1975 they would have been concrete and a similar depth to today – a minimum of 1000mm. 

They do not have to give you notice if the work does not come within the scope of the Act – which, from the information you have provided, it probably doesn’t.