Foundations for a 3bay garage with living space above

Hi Joe. You have to dig your footings until you’ll find virgin ground so the depth may vary. Reinforcement is optional but we always use it when footings are vibra-piled. I wouldn’t go for raft foundation as it will be more expensive. Dig out your foundations to a virgin ground, work out the depth to finish floor level and see what’s going to be cheaper: bricklayers building it to DPC level or massfilling it with concrete. Depends on the ground condition you have to allow at least 150mm of concrete. You can step down your footings if you come across soft ground (like an old backfill, old land drain etc.) as long as the step is not in the corner and it’s not deeper than 450mm. Once you get passed it you can step it up again. When you dig out your footings and it will be a virgin clay, make sure to pour it asap so the clay won’t dry out. Otherwise it will suck out moisture out of concrete and it may crack. If you got any more questions let me know. Lucas

Hi joe . You will need reinforced concrete foundation to a depth of 60mm (0.6mtrs ,600mm , 0.60cm ) industry standards . This will be sufficient for any extension for This height