BUILDING BRIEFING:
BLOCKED DRAINS
- We examine the results of recent consumer research and some typical drainage issues and problems
There is perhaps no single area of property management that generates more queries than the blocked drain. Rapid response is important, yet few people are interested in getting their hands dirty when faced with the inevitable blockage. Scams and overcharging are commonplace yet with some operators charging as much as £200 per hour. As our summary shows, there are some simple but effective products and methods available for self-help, and some useful tips to keep the cowboys away.
In the previous Building Briefing (October 2006, p19), we look at the main types of drainage systems that are used within residential properties. In this following article, we look at some typical drainage problems, and everyday practical solutions. Only by spending some time studying how buildings and drains operate can a property manager learn to diagnose some drainage problems by him/herself, converse on a technical level with maintenance staff, ensure that maintenance and callout charges are reasonable and spot a scam when it appears.
Which? Survey
The Consumers’ Association magazine, Which? recently carried out a survey of plumbers and drain clearance contractors. They set up a typical blockage in a kitchen drain and asked ten firms to come and sort it out. A Which?- appointed drainage specialist estimated that the drain should take no more than 30-60 minutes to unblock, with a fair price for the job (including call-out) of £40. Only 2 of the contractors completed the job within the allotted budget. The eight remaining firms quoted between £42 and £280 for the job. The statistics suggest that overcharging is rife within this sector.
Instructions to tenants
Experienced landlords and agents are generally familiar with the essential architecture of domestic drainage system, but this knowledge and respect does not always extend to the tenants - many of whom are living in their own property for the first time, and unused to regular household maintenance chores such as the unblocking of toilets, sinks and shower trays. It is good practice to leaving tenants with some simple instructions on measures that can be taken to avoid blockages in the first place, and some initial steps they can take to clear a blocked sink or shower tray. Clearly, if simple remedies fail to work, then it is important to alert the landlord or agent of the problem.
Which? advises:
Included below are some simple but useful tips from the Consumers’ Association on good household practice when dealing with sinks and drains. Consider leaving instructions to help your tenants to look after their property better.
- Remove hair regularly from plugholes, as it creates a mesh on which bathroom blockages can start to form
- Hot oil or fat should not be poured down the drain where it can build-up within traps and pipes. Add bird seed to fat, let it set and use it to feed to birds. Otherwise, let it cool and pour liquid oil back into the container it came in, and put it in your dustbin
- If a blockage occurs, try a plunger first. Use a cloth or rubber-gloved hand to seal the overflow so that the plunging pressure does not force debris out through it. If that does not work, then try hot water or a chemical drain unblocker product as these are often successful at clearing more stubborn blockages.
- Never use a plunger after a chemical treatment. The high pressure it creates could blow harmful substances back through the overflow.
- If you decide to remove the U-bend or trap below a sink, have a basin handy. Be careful about spilling chemicals or water when you remove the trap. Don’t run the taps until the trap is re-assembled, and check all the reassembled joints are sealed properly.
Consumer Tests - drain unblocking products
In the September 2006 issue, Which? tested sink unblocking products, on a typical blocked sink (using a cocktail of 14g of hair, soap, toothpaste and cotton fibres, or 18g of fat and food debris). For both bathroom and kitchen blockages, the new compressed air devices came out best, coming with a range of interchangeable heads for use in bathrooms, kitchens and toilets, and blasting away the blockages using a small canister of compressed air. Close behind came chemical products and the traditional rubber cup sink plunger. Of the chemical unblockers, two products based on sulphuric acid and caustic soda were both very effective, whereas other new-fangled cocktails of powder or liquid were, in some cases, less effective than a kettle of water. Extra care has to be taken with acid-based unblockers as they can cause stains and damage to worktops, steel and other surfaces.
Which? Best Buys: Price: Which? Score Available
Mechanical: Power Plumber Plunger Kit £6.99 80% online
Standard plunger/ mini-plunger £1.99 57% DIY store
Chemical: Drain Unblocker - sulphuric acid £3.49 72% R. Dyas
Mr Muscle Active Foamer - £3.49 63% Tesco etc
Traps
Traps are a fundamental component of the modern drainage system and good places to start when looking for blockages. Traps are commonly fitted below each sanitary appliance to prevent foul smells escaping from the drainage system and entering the living space by containing a small volume of water ‘trapped’ in a U-bend. Unfortunately, traps are also the location where debris accumulates and often the first point to become blocked ‘downstream’ of the sink or toilet.
Common ‘trap’ situations are:
• hair and hair products causing blockages to sinks and showeroutlets
• grease blocking kitchen sinks, (and gullies served by them)
• disposable nappies or other solid waste blocking WCs
The yard gully, or trapped gully is yet another type of trap, and a common culprit for blockages as the waste pipes from the kitchen often run directly into them.
Diagnosis
The first stage following any reported blockage is to try and ascertain the nature and position of the blockage. In many cases, a reasonable diagnosis can already be made by information supplied by the tenant over the telephone, whereas in other cases, it will be necessary to make a site visit.
For the individual landlord and small letting business, such calls are generally handled on an ad hoc basis, advising tenants of initial remedies, or handing the issue to a maintenance staff. In larger organisations, and housing associations, a combination of more formal procedures and suitable staff training allow many such problems to be solved by a trained telephone operator with substantial savings in travel and site visits.
It is usually straightforward to determine whether the blockage is internal or external to the property. If, for example, the kitchen sink is blocked and will not drain, but all other sinks and toilets are operating normally. This suggests that the blockage is internal, most probably within or close to the sink. On the other hand, water and unpleasant smells emerging from a leaking manhole cover outside the property suggests that the blockage lies in the external or underground pipework.
Serious blockages
When a serious blockage does occur, there are a host of drain clearance firms that can be called. The problem is choosing between the cowboys and the professionals - recent consumer surveys have highlighted that overcharging is endemic within the drain clearing industry.
It is often a better starting point to locate a trusted local plumber, handyman or building maintenance firm who does have the appropriate knowledge and experience, and can make an initial diagnosis and attempt to rectify the problem. Despite the lavish claims by cowboy drainage contractors, most sink and drain blockages do not require specialist drain pressure-jetting equipment and other expensive inspection equipment.
Over several hundreds of years, plumbers have managed to clear most drainage blockages and similar problems with an array of simple devices ranging from plungers and flexible augers to drain rods. Building regulations require that drain traps exist on most sanitary fittings, and that manhole inspection covers and rodding points (or a ‘rodding eye’) are provided at suitable points along the drainage system. Although drains run underground, they nearly always run in straight lines between the inspection chambers, gullies fittings and stacks. Inspection chambers should exist at every point where pipes join and where the direction or gradient of the drain changes.
It is not unusual to find a property where the drainage system does not conform to the building regulations (or has perhaps been poorly designed or extended) or there are other defects such as crushed or damaged pipes (often by tree roots) where more specialist help will be required. Specialist contractors can now inspect drains internally using miniature CCTV cameras, and provide a cheaper solution than digging up many metres of road or garden. A surveyor can be called upon to advise where there are damaged or badly-designed drains which are prone to frequent blockage. Occasionally, a drain will have to be re-laid, or inspection points added.
Further Information
Two websites with useful tips and techniques for clearing blocked drains: