I am a building novice and would appreciate any advice on what should be done to prepare/complete a solid concrete base for a Hot Tub capable of holding 1200 litres of water. Only four weeks until it is delivered!!
You need 4 pieces of timber 150mm deep and 25mm thick to create a form, or mold, for the concrete. Fix a 50 x 50mm timber to the back of them, horizontally, to geive the boards strength and stop them bowing. Then fix them together, on the ground where you are placing the base and put the concrete in the middle. See our mixing concrete project for help with this.