ᐅ Pouring a slab foundation (4x4 m) yourself: Is a concrete mixer suitable?

Hello,
I want to create a concrete slab foundation with dimensions of 4m x 4m x 20cm (13ft x 13ft x 8 inches). In about one month, a small garden shed made of 175cm (69 inches) calcium silicate bricks will be built on top, which should later be used to store tools and equipment with heavy weight.

The planned layers beneath the slab foundation from top to bottom are: PE foil, insulation, and a compacted gravel layer. The total depth of all these layers is 60cm (24 inches), plus the 20cm (8 inches) slab foundation. The surrounding strip footing (frost protection) is planned to be 30cm (12 inches) wide and 90cm (35 inches) deep.
This results in approximately 3.2 cubic meters (113 cubic feet) of concrete needed, which I plan to mix myself in a ratio of 1:4 (480kg cement: 1920kg gravel + 240 liters water).

Questions:
1. Is a concrete mixer still suitable for this amount, or should I hire a company to deliver ready-mix concrete? I would prefer to avoid the latter due to cost reasons if possible.
2. Are there any other recommendations or tips for carrying out my project?

That’s about 20 loads. It’s doable if you are physically fit.

With us, you can pick up ready-mixed concrete using a trailer. Is there no concrete plant near you? Mixing it yourself is a lot of work and probably doesn’t cost less than ready-mixed concrete... if you can pick it up.

That sounds like a very large quantity; I wouldn't mix it myself. Have it delivered!

That would be around 40 batches with a typical mixer. But it’s possible if you’re very fit. You have to remember that you first need to shovel the 2.5 tons of material into the mixer, then pour it into the wheelbarrow, and finally from the wheelbarrow into the foundation. For one person, I think that’s too much; you’ll need help because all of this has to be done sequentially.

Otherwise, I find that quite oversized. Those quantities are more suitable for a house, not a small shed. What kind of equipment do you plan to store on it?

However, your calculation is also incorrect. The slab alone requires 3.2 cubic meters of concrete, and the strip footing needs roughly another 4 cubic meters.

Wow… a brick garden shed? I have a wooden shed on compacted gravel.