Ratio (cement sand and aggregate) and quantity for concrete slab (10cm deep) 1.5m x 5m please

Are you mixing this yourself?, if so it will be 3 parts aggregate(ballast), to 1 part general purpose cement, not mastercrete or cementone because of additives. But 10cm is not deep enough you will need to be 15cm with reinforcing for that expanse. Plus make sure your sub- base is compacted and adequate enough for the ground structure.

Hi. To answer your question about mixing is 3 aggregate(pipe bedding or similiar), 2 sharp/grid sand, 1cement. I would recommend ordering concrete from Hansons, Cemex etc. whoever is local. Ask for a footing concrete, and they will mix it for you. It might cost you more to mix it yourself First you have to excavate to a solid ground, ideally clay,sand or rock. Work out your finish floor level. I would build my cabin above ground level to avoid flooding and damp. Allow for 100-150 mm of sub-base ( compacted Mot) minimum. If more than that, compact it in layers (150 mm max). Before you pour your slab lay out some visquinn(dpc) so no damp will get into the concrete and your cabin. Let me know what you’re up to and I’ll help you along the way Lucas