Looking for a suggestion of what is an acceptable way of covering drains. I'm building an extension and need to run a new rainwater drain from the front of the house to join with the existing combined drainage system at the rear. I was planning on running the pipe immediately adjacent to the side wall of the house, but was just looking at approved document H1 (incorporated by reference from H3) and am getting a little confused. My depth is going to need to be less than the 600mm minimum under ground level, otherwise it won't join up to the existing drains, so I guess I need a reinforced concrete cover over gravel, but this leaves me with a couple of questions:
1. the diagram (numbered 11 in the approved document) of the reinforced concrete cover shows a 300mm bearing on the ground on either side of the pipe -- what if I don't have 300mm available? Can I join it to the wall to support it somehow, or is there some other way forward?
2. the diagram refers to "compressible material" and text (paragraph 2.44) refers to a "flexible filler"... are these the same thing, and what would be an appropriate material?
1. the diagram (numbered 11 in the approved document) of the reinforced concrete cover shows a 300mm bearing on the ground on either side of the pipe -- what if I don't have 300mm available? Can I join it to the wall to support it somehow, or is there some other way forward?
2. the diagram refers to "compressible material" and text (paragraph 2.44) refers to a "flexible filler"... are these the same thing, and what would be an appropriate material?
