Using old bricks/plaster as hardcore for driveway

[ambercelery]

Hi

I have recently had 2 large brick walls removed in my house and replaced with RSJ's to make a large kitchen diner

I now have a load of rubble in my back garden that I want to get rid of - so will either chuck it all into a skip or use it as hardcore for a driveway on my front garden. Is all this rubble good for hardcore, or do I need to buy hardcore. How far down to I need to dig, to make a good solid driveway - and what do i fill it with.?? i.e rubble for 10cms, then bought hardcore etc....
Any help appreciated.

 

[JohnD]

bricks are OK but not the plaster - it attacks concrete laid against it

if you are on a heavy clay soil plaster and grit improve the texture for gardening though.

 

[The-brickie]

Bricks are great for hardcore as long as you break them up to approx 2" sized pieces and compact with a plate compactor then type one over, say 100mm of brick and 50 mm type one then the sharp/grit sand at 50mm as a bedding, all well compacted.

Avoid the plaster if its the gypsum based stuff as this will swell as it absorbs moisture. Thats why it should'nt be used in bathrooms...

 

[Joe Malone]

The previous contributors are right. Definitely don't use the plaster. It contains calcium sulphate which will react with the Tricalcium aluminate in the cement and form ettringite. It's a process known as sulphate attack and is an expansive reaction which will considerably shorten the life of the concrete slab. You should avoid using any material containing sulphates in your hardcore.