What to check before buying a bath tap

A bath tap has one demanding job: move a lot of water quickly without scalding anyone. Flow rate matters more here than in any other room, since a weak filler can turn a five-minute bath into a fifteen-minute wait, especially on a gravity fed system with a loft tank rather than a combi boiler or unvented cylinder.

Which type suits your bathroom

Separate pillar taps suit a traditional roll top or a period bathroom, and they fill quickly because each tap has its own supply. Deck-mounted bath fillers mix hot and cold through one spout for a tidier look. Bath shower mixers add a handset on a hose, which is the practical choice if your bathroom has no separate shower.

Waterfall fillers look impressive, but their wide, shallow spout needs decent pressure to fill a bath at a sensible speed, so they suit a combi or unvented system better than a low pressure one.

Freestanding baths are the exception to all of this. With no deck to mount on, they need either a floor-standing bath shower mixer with its own pipework rising up through the floor, or a wall-mounted tap if the bath sits close enough to the wall. Plan the supply pipes before the floor goes down, since moving them later means lifting it again.

Measure these before you order

Count the tap holes on your bath and measure the distance between their centres. On many UK baths the holes sit around 180mm apart, but older and imported baths vary, and a deck mixer needs to match your bath exactly. Also check the spout reaches far enough over the rim to fill the bath without dribbling down the outside.

Safety on a bath shower mixer

For anyone bathing children or older relatives, a thermostatic bath shower mixer is the upgrade most worth paying for, since it caps the outlet temperature automatically. If the shower hose can reach down into the bath water, water regulations also expect backflow protection, usually a double check valve or a hose retaining ring that keeps the handset above the rim.

How much to spend on a bath tap

Budget bath fillers start around £30 to £60 and fill a bath reliably, if a little slowly (figures from our last check). Mid-range models from £70 to £150 usually add a stronger flow rate and a smoother mixer cartridge, and thermostatic bath and shower mixers from £150 upward add genuine scald protection on top, worth the extra for a household with children or elderly relatives. Our full guide to choosing a bath tap covers filler versus mixer and deck versus wall mounted in more detail.

Common bath tap mistakes

The most common mistake is buying on looks alone and only checking the flow rate after it's fitted, by which point a slow fill is far more hassle to put right. Check the tap's stated flow rate against your own water system before you buy, not after, and our flow rate guide shows how to measure what your pipes actually deliver.

Wall-mounted bath taps catch people out too. They need pipework buried in the wall behind the bath, so they're a job for a full refit rather than a quick swap, and the tap's inlets have to line up with pipes you can no longer see once the wall is tiled.

Hot water supply is the last thing to check on a bigger bath. On a system with a stored hot water cylinder, a large bath can use up the hot water before it's full, however fast the tap runs, so match the bath and filler to the size of your cylinder.