Part Wall Act (PWA) and 45 deg rule

[excited]

Please help, I'm struggling to get my head around this "45deg rule".

I'm building a side extension, the foundations are is 300mm higher than my neighbours.

The neighbour is 3.20 meters away from my foundations. My foundations will probably go down 1 meter.

So if you draw a line at 45 deg from the base of my foundations and it cuts through my neighbours foundations, Do I then need to send a PWA letter.

excited

 

[cjard]

Struggling to get my head round your post to be honest, can you draw a diagram?

Can't quite work out how a 1 metre deep foundation can be reasoned to be within 45 degrees of a 1.3m deep foundation 3.2 metres away. The other foundation would have to be 300mm away for any point on your foundation to be 45 degrees from the equivalent point on the other foundation

 

[excited]

This is the extract from the PWA 1996.

"excavate, or excavate for and construct foundations for a new building or
structure, within 6 metres of a neighbouring owner’s building or structure,
where that work will cut a line drawn downwards at 45° from the bottom of
the neighbour’s foundations (see diagram B)"

Ill post the image in my folder.




excited

 

[ban-all-sheds]

Ill post the image in my folder.

And then please do steps 9, 10 & 11 as well as 1, 2, 3, 4, 5, 6, 7 & 8.

 

[jeds]

The 45° is measured downwards (at an angle of 45°) from the base of your foundation. So at 3.2m away and 1m deep your neighbours foundation would need to be 4.2m deep for the line to cut his foundation. Not likely unless he has piled foundations.

If your neighbour has a standard foundation and you are 3.2m away you do not need to serve a party wall notice.

 

[excited]

Thanks John, That's just the answer I was looking for.

excited....

 

[ban-all-sheds]

The 45° is measured downwards (at an angle of 45°) from the base of your foundation.

No, it is measured downwards from the base of the neighbour's foundation - it says so quite clearly.

So at 3.2m away and 1m deep your neighbours foundation would need to be 4.2m deep for the line to cut his foundation. Not likely unless he has piled foundations.

But the geometry is the same, only it's his foundations which would need to be excessively deep.

 

[ban-all-sheds]

Thanks John, That's just the answer I was looking for.

And it's exactly the answer shown in the diagram:

Bit worrying that you don't understand that. I hope you aren't doing the plans or drawings for the extension.