Photo: Harry Cooke

What is a waste trap?

designingbuildings.co.uk - Types of waste trap - Designing Buildings Wiki

Do outdoor outlets need to be on their own circuit?

It's common to have a number of GFCI protected outlets on their own circuit if the circuit is protected by a GFCI breaker in the main panel....

Last updated Aug 10, 2020

Why do doors get stuck in winter?

Doors usually stick in summer, when relative humidity is high. The moisture expands the wood, making your doors too tight in their frames. In the...

Last updated Oct 16, 2019

Can I build my own shed?

Yes, with the right plans you can build your dream shed.

Learn More »

Promotion

Types of waste trap

Waste traps or traps are small plumbing devices designed to prevent odours from sewage or waste water leaving the pipe systems and entering the interior spaces of buildings. They can also help prevent the spread of bacteria and insects. They are simple but ingenious devices that generally work by creating an air trap using the waste water of the system, which sits in a small reservoir within in the line of the waste water flow. It is normally a relatively simple plumbing part used in sinks, toilets, showers, baths as well as floor level drains, coming in a variety of types with various terms associated.

edit] Types of waste trap

Some of the more common types of waste trap are described below.

The U-bend is possibly the most common term used to describe a waste trap in the UK. The variations on this type all contain a U shaped form in their design. The U trap was invented by the English businessman plumber T.Crapper in the late 1800's and was an improvement on the S trap which was invented some 100 years earlier. The S trap was invented by A.Cumming who also patented the first flush toilet, it developed into the U-bend, which was an improvement because it did not need an overflow pipe.

Shallow or low-level traps

Shallow or low-level U-traps are based on the same system as the U-bend, but are shallow so that they fit into tight spaces such as underneath showers and bath units. A gully trap or Q trap has a basin in the ground with a water seal for odours and a vent pipe to allow fresh air in. A floor or nahni trap is a shallow design of minimum 50 mm depth provided in the floor to drain and prevent smells entering internal spaces. Nahni is indian for washing area, where these are commonly used. Interceptor traps normally act between the main sewer and building sewer, they have deep water seals of 100 mm to prevent bugs and insects crossing systems and are usually found in the outlet of the last manhole chamber from a property before the main sewer connection and are typically made of vitreous clay. There are many different types such as: The Winser trap, Kenon trap, Bristol trap, Buchan trap, Reverse Interceptor trap, The Radnor, The Netley (reverse action), The Warwick, The Coulsdon and The Salus. A bell trap contains a water reservoir cup which has a bell shaped cover over it that dips at the edges into the water filled cup to form a seal. A straight-through trap or through trap is a compact trap specifically allowing for neat plumbing behind basin pedestals. A P-trap is a u-shaped bend in a waste pipe,containing sitting water, that connects a sink's drain to a septic tank or main sewer system. A bottle trap is attached under a sink to block gases from rising from a drainage systems into a bathroom. Drum traps are often found in older systems functioning in a similar way to bottle traps.