What is a toilet?
A toilet is a sanitary fitting that uses water to carry urine and faeces away to the sewer; the same word is also used for the room in which it is installed. Other names include WC (water closet) and lavatory. A toilet consists of a pan with a built-in trap (water seal) that keeps out sewer smells, a cistern and a seat.
Types
- Floor-standing toilet: the pan stands on the floor. Often a close-coupled model, with the cistern sitting directly on the pan.
- Wall-hung toilet: the pan is fixed to a concealed cistern with a steel frame behind a stud wall. The floor underneath stays clear, which makes cleaning easier.
- Outlet direction: a floor-standing toilet has a horizontal outlet (into the wall) or a vertical outlet (into the floor). Check this carefully when replacing one.
- Dual-flush toilet: with a button for a small and a large flush, saving water.
Building points to watch
- Drainage: a toilet connects to a waste pipe with sufficient diameter and fall, usually 110 mm. The shorter the run to the discharge stack, the lower the risk of blockages.
- Venting: the drainage system needs venting, otherwise the trap can be siphoned empty and you smell the sewer.
- Ventilation: a toilet room needs extract ventilation. The minimum required capacity is set by national building regulations; check the rules that apply locally.
- Fixing: a wall-hung toilet must be mounted on a frame designed for the load-bearing capacity of the floor or wall. A plasterboard stud wall alone is not enough.
Tips for replacing a toilet
- Close the isolating valve and flush the cistern empty.
- Measure the distance from the outlet to the wall and the height of the outlet, and buy a pan that fits.
- Use a new pan connector and seal around the base of a floor-standing toilet, leaving a small gap at the back so that any leak becomes visible.
- After fitting, check that the flush, cistern and connection stay dry.
Related terms
- Drain trap
- Discharge stack
- Air admittance valve
- Mechanical ventilation
- Sealant
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