Going Round the U-Bend?


Newcomers to bathroom plumbing sometimes ask, ‘why do I need a U bend?’

The simple answer is that the water trapped in the U bend acts as a barrier to the foul smells that otherwise rise from the sewer or other drainage pipework. This is why it is an absolute requirement in the building regulations.

As well as being nasty to smell, the gases that swill around otherwise include highly inflammable and deadly methane as well as a potential toxic soup of other nasties, so beware: if smells arise, investigate and put matters to right.

In the case of your bathroom sink, matters are usually straightforward. You or your plumber will install a U-bend, or more normally a ‘bottle trap’ or ‘p trap’ that will neatly protect you and will be easy to unscrew and clean out when it gets clogged up, as it will do, with hair, fatty deposits and calcium in the future.

Falling into the sink trap

Too may of us however overlook the practicalities when boxing in the trap with a cupboard, so please, please get the basics right and allow yourself sensible access to the trap that means it can be easily removed and repositioned without the need for you to develop double-jointed wrists or for you to demolish the unit around it.

Selecting an attractive, even designer chrome bottle trap means you can let it all hang out in a clean and classy way, without the need for concealment.

Hidden depths

Toilet bowls all come with a U bend built in: but matters can become somewhat more tricky when it comes to baths. These are most often boxed in, so if your plumber has skimped on the depth of the U bend then it is a much trickier problem, as is future cleaning: professional rodding can sometimes be required, especially when waste pipes are buried in the ground. Sunken baths are a particular problem in this respect.

Avoid these problems wherever possible by fitting one of the attractive bath panels available from Plumbworld in a range of attractive styles that can all be removed for maintenance. Or here again, you have the option of full disclosure: go for a traditional bath that is designed to show its pipework unashamedly to the world.

Showers also present the issue of limited clearance for installing a proper drain. The big new trend is towards flush-mounted wet room installations. Nobody wants to face a big step up to the shower floor, but without that you need to allow for a good sub-cubicle cut-out. Too often there is very tight space and the flexible type of concertina drain pipe is used, and if the U profile is not well-enough pronounced when installed, then a small layer of water may seep away through evaporation or leakage and cause you a problem that is hard to solve without great cost and disturbance.

Now you know a bit more about u-bends, why not take a look at our range of bathroom essentials such as basins, shower enclosures, taps, and flooring.

If you found this post informative, you might also like - Plumbing Basics - Learn about your home plumbing system - Plumbing Costs Estimates: From an Install to a Pipe Repair - Bathroom DIY: How to Fit a Toilet.

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