How to Plumb In a Washing Machine — UK Step-by-Step
Modern UK washing machines take cold only (most) or hot & cold (some Miele/AEG). Here is the correct plumbing install.
Step-by-step method
1. Fit isolators to hot/cold
Blue = cold, red = hot. Standard washing-machine isolator with 3/4" BSP outlet. Fit to a 15mm tee cut into supply pipes.
2. Alternative: self-cutting valve
Clamp-on valve that pierces the pipe when tightened. £8 and no cutting — but not everyone's favourite for reliability. Keep to secondary duty.
3. Standpipe for waste
32mm plastic standpipe, minimum 600mm height, maximum 1000mm. Machine drain hose hooks over the top — do not push in and seal (it needs an air break).
4. Connect and test
Blue hose to cold, red to hot (if applicable), drain hose over standpipe. Open valves, run a rinse cycle, watch for leaks and drain function.
Frequently asked questions
Cold-only or hot & cold washing machine?+
UK machines mostly cold-only — internal heater warms water. Hot & cold saves energy if you have a solar/heat-pump hot water source.
Can I use a washer/dryer under a worktop?+
Yes — but leave 20mm ventilation gap either side for the condenser to dissipate heat.