With the old basin fitting removed:If this is for a basin, then, there will be no requirement to have an overflow connection because it is a part of the appliance as standard. Usually the waste fitting is set into the basin using washers made of rubber, however you could make a joint by following the procedure below:A). Form and press a ring of plumbers mate or silicone rubber to the underneath the section of the waste fitting that will sit in the basins outlet. So that this joint is successful the appliance needs to be absolutely dry, otherwise the jointing materials used will not adhere to the porcelain. Boiler Repair London fit basin waste fittings.B). Next, fit the waste fitting into its location position and apply a second ring of plumbers mate, silicon or even a large rubber washer to the area around where the thread sticks through the waste hole of the appliance. Now fit a 32mm polythene washer. Wind a large back nut onto the waste fitting, compressing the whole lot together to form a seal. In order to stop the waste fitting spinning in the basin while you are screwing up the back nut, stick two screwdrivers through the slots or grates in the waste fitting and hold it still. As soon as the appliance is complete you can now start what is referred to as a second fix. This means firstly, you need to secure the appliance in its position, making sure it is adequately supported and is level. The top of the appliance is plugged in level as the gradient towards the waste is built into the design of the appliance. Boiler Repairs London use second fixes.NOTE:Plastic bath installations require additional wall fixing clips, that come with provided with the appliance and are supplied to fit in order to stop the bath from sagging as it increases in weight due to the volume of water as it fills.