What causes a blocked pipe?

Pipes sometimes seem to have a mind of their own. In a way it’s like smoking and cancer rates.

We all know someone who’s smoked like a chimney all their life and is still going strong at 94.

But we also know plenty of smokers who die of lung cancer or emphysema in their seventies.

In the same way, some people get away with years of ‘pipe abuse’ at home; paying little attention to what goes down the sink yet never having a clogged drain pipe.

Others are reasonably careful about what they do – yet once every few months they have to call the plumber to unclog the drain.

This article looks at the main causes of drain blockages and discusses some of the more common ways you can unclog your drains and avoiding ongoing troubles.

The case of ‘The Constantly Clogged Drain Pipe’

It’s a real-life mystery. 

I don’t know about you, but at our house we have an ensuite bathroom, a powder room, a laundry and a kitchen. All the sinks and drains in those rooms seem to work just fine. 

But we also have one family bathroom that always smells vaguely like a sewer even after it’s been scrubbed top to toe. The bath takes an age to drain, the pipes gurgle and the kids are always calling me to come and unclog the drain – which is definitely one of the delights of my day!

With a bit of effort, we get the hair out of the grates and after adding various natural and chemical products things clear, but if anything goes wrong with our plumbing it’s always in that bathroom. It can get frustrating when hubby and I have to line up to use the master ensuite but we grin and bear it; knowing that the slightest bit of use in the other bathroom will lead to issues.

So what is the cause?

The same plumber laid the pipework for all three bathrooms, so it’s unlikely it has anything to do with shoddy workmanship. We treat the drains and pipes all the same way (if anything the drain in that bathroom is treated by far the best) so it can’t be about what we are doing. But for some reason it constantly has a clogged drain pipe.

Why do drains get clogged?

There are three things that can lead to a blockage in your drain. 

  1. A buildup of matter – fats, oils, scum, hair, food scraps, dental floss being washed down sinks and other inappropriate items (i.e. if wipes, nappies, paper towels etc.) being put in toilets.
  2. Poor pipe work configuration or laying – which may lead to a naturally occurring opportunity for matter to gather and solidify. This might include a junction that protrudes and traps passing matter, a bend that matter finds difficult to negotiate, or even where building product has fallen in during construction and is now causing a drain blockage.
  3. A break or split which has occurred – which can either be protruding into the pipe and acting as a trap for matter to accumulate, or which has allowed soil to collapse into the drain causing the to pipe collapse.

How to unclog a drain

There are few ways you can unblock your drains. 

Cheap and easy: If it’s a one-off, rather than a regular occurrence, you can try the simple strategies like pouring half a cup of cheap dishwashing liquid down the sink and following it with a good dose of warm water. A good way to do this is to pour most of the dishwashing liquid into the drain and then put the plug in. Don’t use the sink (or any connected to it) for about half an hour. After that, tie a string around the plug hook (or around the metal nob on an inbuilt sink plug/waste) and fill the sink with very hot (almost boiling) water. Add a bit more dishwashing liquid and mix. That done (having waited the half hour) remove the plug with the string and let it all slide down the drain. This should work to break up any blockages that are mainly fat or oil based. If you feel extra hot water will help, simply repeat a few times. 

Stepping it up: If the ‘soap and water’ trick doesn’t work, you might need a bit more help. There are some commercial drain cleaning products that many claim get great results, but always make sure they are biodegradable. Some also swear by mixing bicarbonate soda with vinegar, however this works best when blockages are near the drain entry.

Using equipment: There are then things like plungers and drain snakes. Plungers work well to clear blockages, however drain snakes should not be used unless you are qualified and know what you are doing. 

Pulling out the big guns: If nothing else works (or if your drain blockages are a regular thing) you should enlist the services of a professional for your blocked drain repairs.  

If you don’t have someone you know you can trust, check with friends and neighbours for recommendations and read internet reviews of larger companies. Ensure the drain technician you enlist offers CCTV camera inspections and are able to conduct pipe relining if needed, as this will avoid the need to dig up your pipes if there are any breakages that are causing your blocked drains. 

This article provides more information about clearing blocked drains. 

How to avoid a drain blockage

Avoiding drain blockages is as important to your wallet as avoiding blocked arteries is to your health. But it’s really a lot simpler to achieve.

10 Simple Tips to Help You Avoid Drain Blockages

Avoiding blocked drains is as important to your wallet as avoiding blocked arteries is to your health. But it’s really a lot simpler to achieve.

  1. Never let fats, oil or grease go down the sink.
  2. Scrape food scraps into the bin before rinsing plates.
  3. Install a sink strainer in all sink wastes and empty them regularly into the bin.
  4. Dose your kitchen pipes with hot water and dishwashing liquid regularly.
  5. Only flush the Three Ps: pee, poo and (toilet) paper.
  6. Install a hair snare in all bathroom sinks (shower, bath, sink).
  7. Put a bin in the bathroom for other waste (floss, wipes, sanitary products etc.)
  8. Put up signage reminding everyone of what can’t be flushed.
  9. Never put paints or harsh chemicals down your pipes.
  10. Initiate a regular plumbing maintenance program.

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