You are reading a single comment by @Polygon and its replies.
Click here to read the full conversation.
-
Nice one, I was considering concrete on top of the subbase depending on the build up required, but you reckon it'll be ok going straight on the soil? It was my understanding that a subbase ensures even load on a concrete base but maybe that's just for high loads, this will be foot traffic only. It's fairly firm ground as I took away all the rubble filled crap, just needs leveling properly and the weeds killing off. I reckon I'm about 4-6" below where the slabs need to be currently, I need to get a grade rod and check.
Polygon
ColinTheBald
My advice always begins and ends with 4" of concrete under a patio. By the time you add mortar and surface material that will be about 6" deep and going precisely nowhere.
Many 'professionals' will suggest compacted type 1, this is because it is easier and gives a better profit margin. They will tell you that it is going in 6" deep (which is the minimum needed on anything other than completely solid ground), in reality you will be lucky to get 2". The consequence is that the whole lot will move and crack, but they'll be gone and operating under a new company name by then.
If you do want to use roadstone, dig out a minimum of 8" below finished level (as opposed to 6" for concrete) and remember to compact with a Wacka plate every 2" of depth. If the soil isn't solid at 8", keep digging until it is!