How deep can you use shingle/stones?

[lukey_boy]

Hi all,

I am currently doing some work on my house, and I had to digg away earth from the back and side of the house so that I do not bridge the DPC.

So now I have a nice gully of about 2.5 metres wide. I Have dug down about 5 bricks below the DPC.

I was going to put pea shingle down (to assist with drainage) for about 2 bricks high, and then finish off with a nicer stone (maybe red granite) for about 1 brick high.

This will take me up to about 2 bricks below DPC.

The problem is that there is clay underneath, and the garden is riased, so the water is going to run down. So I have drainage in mind.

Questions:

1. Should I lay any sand/hardcore to help with drainage?
2. DO i need to lay a membrane in between the courses of shingle and red granite finsh stone?
3. Will this stone be too deep, and be like walking on sand with me sinking in to it all the time?
4. Any reccomendations on good stone to finish with?

Thanks very much

[lutonlagerlout]

worth putting some proper land drains in mate to get the water away,any sort of shingle finish should only be twice the depth of the aggregate,so if you use 20mm shingle as i have done at home you want 40-60 mm of aggregate in total,this should be on top of a membrane or type 1 stone that has been compacted,if its too thick (as mine is in places just waiting for an oppurtune moment to remove it) your feet/car will sink in
hope this helps
LLL