How they work
A macerator unit sits behind or beside the toilet. When it's flushed, a pump with cutting blades breaks the waste down and pumps it through a small-bore pipe to the soil stack or drain. Because the pipe is narrow and pumped, it can run upwards or a long way horizontally, which gravity drainage can't.
Similar pumps are made for showers, basins and utility sinks below drain level.
When they're used
- Under-stairs or cloakroom toilets far from the soil stack
- Basement and cellar bathrooms below the drain
- Loft or garage conversions with awkward drainage
- Extensions where a gravity drain run isn't practical
Need a plumber for this?
Describe the job and compare free quotes from plumbers near you.
- Free to use
- No obligation
- Compare local plumbers
- Quick online form
You'll continue to our quotes partner, MyJobQuote, to describe your plumbing job.
Rules and limitations
Building Regulations guidance generally expects a macerator WC to be an addition to a conventionally drained toilet in the property, not the only one. The unit needs an electricity supply, makes some noise when running, and must be accessible for maintenance.
Only toilet paper and human waste should go into a macerator. Wipes, sanitary products, cotton buds and even large amounts of paper are common causes of breakdowns.
Common problems
Units that run on, cycle on and off, smell or refuse to start usually have a blockage, a scaled-up switch or a failing pump. A plumber familiar with macerators can service or replace the unit. Keep the manual and model number handy, as parts are specific to each manufacturer.
