Trap (siphon) replacement

The trap under a basin, sink, bath or shower tray holds water in its bend, which blocks smells from the drain. When the trap cracks, leaks at the joints or furs up so badly that cleaning no longer helps, replacing it is a quick way to a dry cabinet and a bathroom that does not smell.

When to replace a trap

• it drips under the basin or sink even with the nuts tightened;
• the drain smells of sewage and the water in the trap disappears;
• the drain keeps clogging and the problem returns soon after cleaning;
• the trap is cracked, or old and made of brittle plastic;
• a washing machine or dishwasher is being added and a trap with a spigot is needed.

How the replacement goes

The handyman unscrews the old trap, cleans the waste outlet and pipe, then chooses a new trap to suit the waste and the space in the cabinet. Under a vanity unit, a space-saving trap that leaves room for a drawer is a common choice. On baths and shower trays the trap is often hidden behind a panel, so access through a hatch or removing the panel is needed. Finally, the water is run and every joint checked.

When the problem is further down the pipe

If water still drains slowly after a new trap, the blockage is deeper in the waste pipe or the stack. Then drain cleaning with a snake helps. The handyman will tell you where the cause lies before replacing parts that work.

Common questions