I am building a pizza oven and kitchen area in my garden. I am trying to work out how to lay a 2m*2m concrete slab.
My calculation for the weight (that the concrete slab needs to support) are
Dense bricks: 70 * 18.2kg = 1,274kg
Concrete slabs: 13 * 15kg = 195kg
Pizza oven: 1 * 50kg = 50kg
Total: 1,519kg
I did some research to find out how much concrete (with reinforcement bars) I need but it may turn out the bigger issue is what the concrete will be laying on (how much weight a specific sized concrete slab can carry?)
How do I determine this? In my case, I want to pour the concrete slab over mud, which I would have dug out to size (with a timber frame as well). I was hoping to pour a layer of gravel down but I'm not questioning if that is going to be enough.
I believe our soil is quite chalky.
How do I prepare the ground before laying the concrete slab in the UK?
Best Answer
You definitely shouldn't pour concrete over mud. Also, I guess your local can get quite cold during the winter, thus you need to dig the soil, at least, down to the frost depth to avoid differential settlement due to heave. The soil is considered "competent" if it can support the weight above without significant settlement. You can get the information from the local building code, a engineer, or an experienced contractor. Below is the suggested details.