Dealing with plumbing emergencies

Plumbing disasters can range from the devastation of a burst pipe, to the unpleasant pong of a blocked sink. Most problems can be avoided if you keep your plumbing and heating systems well maintained. However, when emergencies hit, our top tips are here to minimise the damage before your plumber arrives.

Cold weather related emergencies:

When the minus temperatures hit, water within exposed and uninsulated pipework can freeze. As water expands when it turns into ice, this can damage pipework, causing it to split. If you are lucky, a split may be minor and only cause a little damage - maybe only noticeable in a drop in pressure to your boiler, or an unusually high water bill - but a major leak can be devastating and cause similar damage to a fire.

Burst pipes can be caused by other issues too. A stray nail or screw is often a culprit, especially when DIY season begins.

Whether your burst pipe is weather or accident related, there are a number of steps to take. The first is to try not to panic and keep a clear head while you:

  • Prevent water passing the point of the leak by turning off the stop-valve on the incoming water supply main - often sited under the kitchen sink.
  • If there isn’t an internal valve, turn off the water at the external valve - often found under a cover in your garden or path.
  • If the escaping water cannot be controlled immediately, open all COLD water taps and flush the WC so that the pipework and storage system drains quickly.
  • Turn off the central heating system and, if it uses a solid fuel boiler, allow the fire to die out. Switch off any electric immersion heater, then call a professional plumber.

If a pipe freezes these are the steps you should take:

  • Turn off the mains water supply at the stop valve inside your home.
  • If the frozen pipe runs from a storage cistern and is not controlled by a valve, check that it hasn’t split. If it has, empty the cold water storage cistern by opening the cold water taps and flushing the WC. If you know how to, you could siphon the water from the cistern with a hose pipe, then call a professional plumber.
  • If the pipe isn’t split, thaw it out by applying hot water bottles.
  • If any part of the hot water system is frozen, there could be a risk of explosion if the boiler (or other heat source) is kept alight, so ensure it is turned off, or for solid fuel systems, extinguish the fire.
  • Be careful as although water may be flowing from taps, other parts of the system may still be frozen.
  • Don’t try to thaw pipes too quickly as there may be splits in the pipe which are not immediately noticeable.
  • Never use a naked flame to thaw a pipe.
  • Always start thawing a pipe at the end nearest the tap.

Boiler breakdowns in exceptionally cold weather can be due to a number of reasons, hence you should always consult with a professionally registered expert. However, there are some common cold weather related issues:

  • When the temperatures drop below freezing, the condensate pipe on condensing boilers may freeze. This will cause the boiler to shut down.
  • Burst and frozen pipes can also cause a boiler to malfunction (see above).
  • Boilers that have not been regularly maintained are more likely to breakdown.

If the breakdown is due to a frozen condensate pipe, and your professional is familiar with your system, they may be able to talk you through defrosting the condensate pipe over the phone.

You should only ever attempt defrosting condensate pipes that are at ground level and if you feel confident to do so. If your condensate pipe is higher, or you are unsure, call in the services of a professional heating specialist.

Many boiler issues can be avoided if systems are regularly maintained. The CIPHE recommends annual servicing, before the heating season begins, to keep systems safe, efficient and effective for the year ahead.

General plumbing and heating emergencies:

If you can smell gas you need to act quickly to let the authorities know as gas is highly flammable. The National Grid operates a free, emergency, 24 hour telephone number on 0800 111 999. Deaf or hearing impaired can use a minicom / textphone on 0800 371787.

If you can smell gas in your home:

  • Never ignite a naked flame / strike a match etc.
  • Never touch any electrical appliance (including light switches).
  • Put out naked flames.
  • Open doors and windows.
  • Keep people away from the affected area.
  • If you have access, turn off the gas supply at the meter using the control valve.

When fat or oil (animal and plant based) is poured down the drain, sink or WC at a temperature above its melting point, it will then cool and solidify and this can cause blockages resulting in:

  • Problems flushing the toilet
  • Issues draining water from sinks and baths
  • Bad smells
  • Contamination
  • Major inconvenience and costs.

Make sure you dispose of fat, oil and grease (FOG) correctly. Let it solidify and put it in a disposable container (like a used margarine tub or yogurt pot) and then empty it in the bin. Never pour it down the sink or into a mechanical WC. People pouring cooking fats into the kitchen sink or toilets, is the number one cause of blockages in drains.

If you do experience a blockage due to FOG:

  • Empty any surplus water remaining in the sink.
  • Add some washing up liquid and pour boiling water from a kettle onto the sink outlet to soften any hardened fats. Then, turn on the hot tap to flush any deposits through.
  • If this has not dislodged the blockage, you can use soda crystals (following the directions on the box).
  • If this does not clear the blockage, then it is time to call a professional.

You should only ever flush the three P’s - pee, poo and (toilet) paper – down your lavatory. This is what your plumbing and sewerage systems were designed for. The pipes are relatively small and easily blocked and there really isn’t much room for anything else to pass through.

This means that everything else should go in the bin, and especially includes:

  • Any type of disposable wipe – baby wipes, make-up wipes, antibacterial cleaning wipes etc, even if it says it is flushable.
  • Paper kitchen roll, paper hand towels or any other type of paper product that is not toilet roll.
  • Any type of cotton wool product, including cotton wool pads and cotton ear buds.
  • Sanitary items such as sanitary towels and tampons, including any of the packaging they are supplied with. This also includes incontinence pads and liners.
  • Nappies.
  • Contact lenses.

The CIPHE always advises using a professional plumber to unblock a toilet. However, if a person is shielding or self-isolating due to covid-19, it may be appropriate to remove the blockage themselves.

  • Unblocking a toilet is not going to be nice. You must wear long sleeved rubber gloves and safety glasses.
  • You will probably require a bucket of hot water as this might help dissolve things. If you’re going to put any chemicals down the toilet, beware they give off fumes and doors and windows need to be open.
  • Drain un-blocker chemicals are very powerful and can be very dangerous if breathing in, getting on your skin or eyes. Always read the manufacturer’s label to see what they recommend for its correct safe use. If in doubt, don’t use it.
  • Make sure you wear old clothes, or manual work clothes - they will potentially be contaminated afterwards and will require washing separately.
  • Make sure the area has been protected with old newspapers / dust sheet etc and that you have removed as much as possible from the toilet area. Splashing might occur and therefore removing items nearby will help.
  • You would start with a plunge/force cup if you have one. Otherwise you might use a traditional mop, but it is very important this is not used thereafter. By plunging the force cup (or mop) down into the outlet, you start a momentum of pressure - as it is pulled backwards the contents ought to be sucked out by the pressure created.
  • Once clear, flush the WC several times. Thoroughly clean down all areas around and within, including the underside of the seat to ensure there is no contamination.

Don’t wait for a slow draining toilet to get worse. Take action as soon as you suspect there may be an issue.

If you have a mechanical WC (macerator) then the guidance hasn’t changed. Macerators only take toilet paper, anything else will block the motor and cease it. This will lead to failure and potentially great expense. Always follow the manufacturer’s instructions. If your mechanical WC is blocked, call in the services of your professional plumber ASAP.

The CIPHE does not recommend DIY tasks on drainage systems, especially outside. This is because when you lift manhole covers they can be heavy, deep or when exposed they make the area un-safe, unless you know what you are doing.

In the case of external blockages you must get an agreed cost form a professional engineer. This might be per hour, call out charges or for specialist equipment. Don’t go forward with open ended cost. If you need to call in professional help, make sure you engage the services of a member of the CIPHE. 

If you need to seek the help of a professional, you can find plumbing and heating engineers via our find a plumber tool, by phoning 01708 472791 or emailing

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