When laying the concrete please keep in mind the length of time it will take for the concrete to cure. Do not expect to site your building on a newly laid concrete pad.
For most buildings a concrete thickness of 3″ (75mm) is fine, on some of the larger buildings & depending on use increase this to 4″ (100mm) laid on compacted hardcore or Type 1 roadstone may be required. Approximately 1″ -2″ (25-50mm) of the depth of the base should be above the surrounding ground level.
Tip: It is advisable to place a polythene membrane down prior to the concrete being laid to prevent damp rising through the concrete to the building.
These quantities are for guidance purposes only. Always order more than you have calculated being needed. It’s easier to return unused material than to get more materials as the concrete is going off.
Mix to the ratios that have been decided, in this case 1:5 whether it be 1 Shovel of cement & 5 shovels ballast, or you use 1 bucket of cement & 5 buckets of ballast, use of the same measuring device is essential.
As soon as the concrete has hardened enough not to be marked, it should be covered with a plastic sheet and weighted down.
Note: Concrete should not be allowed to freeze; additives or insulation during the drying process may be needed.