The Brew Cabin

Posted: **Sun Jun 20, 2010 10:08 pm**

We want to build a set of 3 steps between 2 levels in our garden. Each step 800mm wide, 400mm tread, 150mm riser, giving an overall 450mm rise over 1200mm distance. The 800mm x 1200mm area for the steps is currently all at the lower level, which is clay based subsoil. We plan to build them from pieces of spare cornish slate walling stone, mortared together.
What would be a suitable base? We were thinking of a concrete slab (800mm x 1200mm), say 100mm thick. Also would low density blocks be OK as filling under the higher steps?

Posted: **Mon Jun 21, 2010 12:30 am**

a concrete base is a must, and you need concrete blocks for outdoors,lo density are not suitable
or alternatively class b engineering bricks
LLL

Posted: **Mon Jun 21, 2010 8:06 am**

Thanks LLL.
We'll use concrete blocks. Would 100mm be thick enough for the slab?

Posted: **Mon Jun 21, 2010 5:47 pm**

depends what your subgrade is
if its chalk or rock yes
if its clay then really 225mm of concrete
its hard to say without looking sarah
cheers LLL

Posted: **Wed Jun 23, 2010 10:30 pm**

Thanks for the advice LLL.
Sarah

The Brew Cabin

Building stone steps