I have a question regarding a new patio construction on my garden. I have excavated 15cm below the required level of the patio (the slabs will be 32mm deep so I am planning to do approx 80mm hard core and 40mm bedding mortar - open to changing this ratio if there is a better one?). The patio will only be used for foot traffic and maybe a table / chairs.
The issue I have is that there is a large area of wet clay (see image below for the area) that is pretty unstable (varying amounts of unstable - in the worst bit I was able to poke my foot in a couple of inches deep) under foot at the moment, what's the best way of dealing with that under the base I'm planning to do?
I will also need to construct a small (maybe half a foot high) retaining wall - is it better to build the wall before the patio as the foundation will probably need to be under the patio's?
Thanks in advance for any help you can provide
