Foundation size

[pcsparky]

I am going to have a free standing garden wall built in an L shape from dressed stone under 1m high.

I'm not sure yet what width the stone will be. Can anyone tell me please the formula I will need to work out the width and depth of the foundation I will need and what depth the top of the foundation needs to be below the ground level. Also does the foundation have to extend beyond both ends of the wall? Thanks.

 

[DSA]

There is no magic formula! You need to consider local ground conditions.

 

[noseall]

generally, if you dig down about 600mm or so and lay a foundation that is 200mm wider than the wall you should be ok. this will allow a 100mm projection of concrete each side of the masonry.

150mm thickness of concrete will be ok.

these pointers apply to a 1m high wall, digging into undisturbed virgin earth and are a guideline only. common sense will tell you that if you are fishing out beer cans and old kettles after 600mm then dig on.