Unblocking a Sink

The most common cause of blockage is improper amounts of waste put into the sink. Quantities of hair present challenges for any drainage system but with the U Bend or P trap systems used in most UK homes, hair is a big problem. We hope you find this unblocking a sink article useful.

The best way to reduce the chance of backed up drains is to maintain them on a regular schedule. Purchase a drain cleaner, carefully read the instructions and use the cleanser once a month. In the long run, this can save you a great deal of frustration, time and money.

But, many UK residences have outdated piping and drainage systems. These are generally inefficient and overtaxed. In the UK, outdated sink drainage systems can back up with seemingly uncommon frequency.

Understanding the Drainage System

The most common sink to fail is the kitchen sink. While improper amounts of food stuffs being expected to drain is the biggest reason sinks do not drain properly, there can be other, legitimate causes for the backup.

All drains in the house, including sinks, showers, bathtubs and toilets drain into a central drain. This foul water drain takes waste water and waste byproducts from the house to the main sewage system. The main sewage system can also be the cause of backups, but these are rare.

The main cause of poor drainage in sinks is found at the U bend, which is that part of the pipe that resembles a U shape. Detaching and clearing the U bend can be a messy, dirty process. Rubber gloves should be worn when unclogging any sink or toilet.

Preliminary Steps

Before disconnecting and clearing the U bend, a few preliminary steps are in order. If the sink is holding good amounts of water and waste, it is best to empty sink. Manually remove the water to a bucket.

You may want to insert a hanger or soft metal product into the drain and see if you can loosen any residue. If that fails, stick your palm fully over the drain opening and perform a hand plunging motion.

If both of these efforts fail, it is time to bring out the trusty plunger. Place the mouth of the plunger over the drain opening being sure to create a total seal. Then, plunge fairly vigorously. This may well loosen materials caught in the U bend and free the drain. If you feel the plunging was successful, run a good amount of water through the system to ensure the bend is clear.

If Plunging Fails

90 percent of kitchen sink and bathroom sink drainage problems occur in the U bend or P trap.

If plunging does not clear the system, things can get interesting. First, clear any stored goods or products from under the sink. You will want a clear workspace.

Round up the following tools:

  • Another bucket that will fit under the sink.
  • Waterproof tape (May not be necessary but it never hurts to have tape around.)
  • Screwdriver
  • Towel or Cloth
  • Rubber gloves

Try to get comfortable in the prone position with access to the U bend. Be sure you can reach your tools.

The U bend will have two sets of threads, one directly underneath the sink and another near where the bend finishes.

Step by Step Guide to Unblocking a Sink

Step One By hand, unscrew the threads that are directly beneath the sink.

Step Two Pull the end of the drain free.

Step Three Place the towel under the sink, under the U bend.

Step Four Place the bucket on the towel, in line with the U bend. This is where the waste will be captured.

Step Five Unscrew the other threads at the end of the U.

Step Six Remove the U bend and be prepared for a splash as the residue comes free and falls into the bucket.

Step Seven Probe with the screwdriver or wire coat hanger both pipes leading to and from the U bend.

Step Eight Clean the interior of the U bend thoroughly.

Step Nine Remove the towel and the bucket to a safe, dry place away from the immediate workspace.

Step Ten Re-attach the pipes being careful to tighten the fittings but not to over-tighten them.

Step Eleven If you are not confident with the security of the threads, use the waterproof tape to wrap around the fittings.

Step Twelve Run water through the system to ensure the drain is clear and there is no backup.

Unblocking a sink

If there is backup, the problem is more serious than a do-it-yourselfer should try to repair as the waste-water drain may need to be cleared. This should be performed by an expert as a break in this line could become very expensive to repair and might include excavation.

Unclogging the U bend can be a tedious, awkward and dirty undertaking. If you want family members to help prevent future backups, encourage them to participate in the sink clearing process. Chances are good that they will be more conscientious about what goes down the sink if they think they will be unclogging it.

If the sink is clogging at a high rate of frequency, it could indicate that a more serious problem is in the making. Likewise, encourage your household residents to report slow draining sinks or clogged sinks as soon as the early symptoms arise. This will greatly increase the chance of resolution by plunging.

If the sink has a grinder or automatic disposal, refer to the operators manual for specific disconnect instructions. Make sure that all electrical current to the disposal is off before probing or disconnecting any pieces. This is extremely important.

In many disposal systems, there are instructions for unclogging the disposal. In most cases, the do-it-yourselfer can disengage the disposal fairly easily but never when the power source is connected or on. Be sure to actually remove the plug when possible. If you are uncomfortable with working near the disposal, call a plumber.

Hope this guide helps but with every other household do-it-yourself repair, caution is advised. We do not want to make a bad situation worse.

Have you checked out our plumbing and heating tips page?

We maybe able to help you isolate the mains water, fix a leak or unblock a toilet, before having to call out an engineer. Also please read our gas safety article which has been written to help keep you safe.

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Red Van Plumbers
Unblocking a sink April 25, 2014