Wilmington Plumber Tip: Different Kinds of Plumbing Traps

Appliances that use water and are installed inside a house all require some form of a water trap in the waste pipes to provide a water seal to drains or outside atmosphere. These traps are important in preventing bad odors from entering the house, as well as keeping out bacteria and insects.

The Wilmington, DE plumbers at Boulden Brothers have provided you with some examples of the most common plumbing traps that can be found:

The ‘P’ Trap

The ‘P’ trap usually has a screw joint half way along so that when it’s installed the outlet can be moved through about 270° in the horizontal plane so that it will mate with a horizontal waste pipe coming in from an angle. One benefit of the ‘P’ trap is that after it’s installed it can be removed for clearing blockages, or any other problems, and the remainder of the pipe will not be affected. A downside to the ‘P’ trap is that its formation needs a good amount of space in order to fit within the rest of the waste outlet.

The ‘S’ Trap

The ‘S’ trap usually has a screw joint half way along so that when it’s installed the outlet can be moved through about 270° in the horizontal plane so that it will mate with a vertical waste pipe coming up ‘off center.’ The advantages and disadvantages of the ‘S’ trap are the same as the ‘P’ trap.

The ‘Bottle’ trap

The ‘Bottle’ trap usually unscrews at the bottom as a means by which to clear blockages. The output for the waste pipe is always horizontal. The ‘Bottle’ trap takes up less radial space under a waste outlet and is ideal for pedestal mounted sinks where space is usually very limited. They can, however, be deeper that the ‘P’ and ‘S’ traps.

The ‘Shallow’ trap

The ‘Shallow’ trap is most often used on devices, such as baths and showers, where there isn’t much space above the floor. Where fitted to a bath, a banjo connector is normally used above it for the overflow from the bath. This type of trap doesn’t always meet regulatory standards for water seal depth. In instances in which there isn’t an alternative to fitting a shallow trap, it will be necessary to run a deeper trap further along the pipe where space allows, and definitely before the pipework enters a stack pipe, or discharges.

The ‘Shallow’ trap with a connector for the bath overflow.

Similar to a shallow trap described above but with an addition inlet in the bend. Usually this type of trap is supplied with a blanking plug fitted in the second inlet and a separate connector for this inlet must be purchased. The point of the second inlet is connecting the hose from the bath overflow. This removes the need for a banjo connector above the trap, allowing these traps to fit where space is very limited.

These ‘Shallow’ traps have the same challenges as an ordinary shallow traps in that in instances where there aren’t alternatives to running a shallow trap a deeper trap will need to be run further along the pipe line.

Call the Wilmington, DE plumbers at Boulden Brothers if you have further questions.