Shut off the water supply and empty the pipes, tank and taps safely before repairs or leaving a house empty.
DR-01Gather your kitYou'll need a garden hose long enough to reach an outside drain, a bucket, old towels, a torch if you have a loft tank, and a screwdriver or spanner for the drain-off valve. Do this drain-down when you're not in a rush — some systems take a while to empty fully.
DR-02Turn off the water at the stopcockTurn your stopcock clockwise until it stops. This shuts off mains water to the whole house. If it's stiff, don't force it hard — a gentle steady push usually frees it, and a squirt of penetrating oil left for a few minutes helps on an old one.
DR-03Check for a loft cold water tankIf you have a combi boiler or an unvented cylinder, you probably have no tank in the loft — mains water feeds everything directly, so skip to the next step. If you do have a loft tank (common with older hot water cylinder systems), find the valve on the pipe feeding it and turn it off, or tie the ball valve arm up so no more water enters as it drains.
DR-04Switch off the boiler and immersion heaterTurn the boiler off at its control panel and switch off the immersion heater if you have one. This stops them trying to heat water once the system is empty, which can damage them.
DR-05Open all cold tapsOpen every cold tap in the house, starting with the ones upstairs or highest up, then working down. This lets air in and starts the water draining out of the pipework by gravity.
DR-06Connect a hose to the drain-off valveFind the drain-off valve — a small tap with a hose connector, usually near the stopcock or at the lowest point of the pipework, often under the stairs or in a cupboard. Push the hose on firmly and run the other end outside to a drain, gully, or a large container if you have no easy outside route.
DR-07Open the drain-off valveUse a screwdriver or spanner to open the valve slowly and let the water run out through the hose. If your system has a separate drain valve for the loft tank or the hot water cylinder, open those too, one at a time, so you don't flood the area.
DR-08Flush the toiletFlush each toilet in the house to empty the cistern. This clears water that won't drain out through the taps or the drain-off valve.
DR-09Check the system is emptyLeave the taps and drain-off valve open until water stops running. Give it a few extra minutes — pipework holds air pockets that can trap water further along. Once nothing more comes out, close the drain-off valve and disconnect the hose.
DR-10Tidy up and note valve positionsMop up any spills and coil the hose away for next time. Make a mental note (or write it down) of which valves you closed, so you know what to open again once repairs are finished and you're ready to refill the system.
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