Block Paving

[Tony Milner]

Hi Tony. I hope you can help. I am putting a block paved driveway in at my house. Having dug the earth out to a depth of about a foot I laid an initial 3 inches of MOT and used a wacker plate. Having finished this I noticed an area where the MOT moved and could be compressed by simply standing on it. We used the wacker again but if anything it made it even worse. I took the MOT off and found the earth was very soft and sticky. I dug out another foot hoping to get past the soft earth but it is has not improved. I dug a pilot hole about a foot square to see if I could find a solid base but having gone down another three foot there is no improvement. The earth itself seems to have a high degree of clay in it and is very wet. I don't really want to excavate to more than 5 foot from the finished level if at all possible. It has been suggested that if I lay a foot of hardcore in, wack it down to give me a base and then continue with MOT etc this would support the driveway. Do you agree or is there something else I can do? I don't want to cut corners and find the driveway starts sinking in a year or two. The total area of the drive will be 24 foot by 21 foot but the area affected is down one side and measures about 8 foot by 20 foot.

Thanks for any advice you can give.

[84-1093879891]

Dig down deep enough to accommodate 225mm of DTp1 and then lay a geo-membrane such as Terram (see the latest News Page for info on a new range of 'Handy Packs' from Terram) over the levelled-off sub-grade. The sub-base is laid over the membrane and I'll bet you find it works a treat!

[Tony Milner]

Thanks for the advice, I appreciate that.

Tony