Mega-Rod logo

The Problem with Pitch Fibre Drains

Request a call back from our team
Enter your contact details and we'll call you back

    Are you responsible for a property that dates back to the mid-20th century or had its drainage system altered during that period? If so, your wastewater could well be flowing through pitch fibre drains – and drainage issues may be present or just around the corner.

    This problematic pipework was introduced across the UK during the 1940s when the country urgently needed an alternative to traditional fired clay drains due to wartime materials shortages. Pitch fibre drains continued to be used for homes, businesses and other properties until the 1970s, at which point more durable, reliable plastic pipework became the norm.

    Initially, pitch fibre pipes seemed ideal for all sorts of building projects. ‘They were thought at the time to be the latest wonder material, being cheaper than fired clay pipes, and also lightweight and easy to handle,’ construction industry expert Jeff Howell remarks in The Telegraph. However, people’s confidence was misplaced, as many miles of pitch fibre drainage have failed to stand the test of time.

    As our Bristol and Bath drains specialists will tell you, it’s important to check whether your property or a property you’re in the process of buying has this type of pipework. Thankfully, all you need to do is ask us to conduct a CCTV drain survey or homebuyer’s drain survey using our agile, powerful cameras, as we’ll explain.

    A row of terrace houses in Bath built around 1940 and most likely to have pitch fibre drains.

    High Risk of Developing Structural Defects

    Pitch fibre is made from insoluble, fibrous wood cellulose (the main component of trees’ cell walls) soaked in coal-tar pitch (a thick, waterproof substance formed when coal tar is distilled during industrial processes). So although it certainly wouldn’t win any awards for being environmentally friendly, it does have the kind of qualities drains need to carry wastewater effectively. As long as pitch fibre pipework is in excellent condition, it’s fairly strong, can withstand being exposed to water, and is unlikely to spring a leak. You can see why it appealed to construction companies all those years ago.

    However, there’s a major problem with drainage systems that rely on this material. Pitch fibre is particularly prone to structural instability as it ages, especially if the drains have weak joints and are poorly bedded. That’s often the case with pipework used for housing estates, schools and other low-budget, fast-turnaround building projects completed between the 1940s and 60s. As the typical lifespan of a pitch fibre drain is only 40 years, numerous properties across Bath, Bristol and beyond could well have drainage systems that aren’t fit for purpose anymore. In fact, it’s not uncommon for Victorian or Edwardian clay drains, for example, to age better than pitch fibre ones.

    Fat, Oil and Grease Lead to Delamination

    Why is it so common for pitch fibre drains to develop structural defects as they get older? The reason is that they react badly to prolonged contact with three drain-clogging substances that often end up being poured down plugholes – fat, oil and grease – as well as hot water.

    When pitch fibre pipework was first used, that behaviour wasn’t a major concern. After all, ingredients such as butter, margarine and cooking fat were rationed and rapid-boil electric kettles hadn’t yet been invented. But as food history data from the government indicates, lifestyles have changed dramatically since then. Processed convenience foods (which tend to be fatty, oily and greasy) have been commonplace since the mid-1950s. Plus, people boil more water these days as it’s so easy.

    As a result of being exposed to large amounts of fat, oil, grease and hot water, pitch fibre pipe walls often separate into thin layers (a destructive process known as delamination), leading to blisters and warping. Deformed pitch fibre drains restrict the flow of wastewater, are likely to move, leak and suffer from root ingress, and easily get blocked. In severe cases, they may even collapse.

    Identifying and Repairing Pitch Fibre Drains

    Fortunately, Bath and Bristol property owners and homebuyers, as well as those based in the surrounding area, can rely on Mega-Rod to address any concerns they have about pitch fibre drains. During a CCTV drain survey or homebuyer’s drain survey, we can identify pitch fibre drains and any drainage issues then suggest a plan of action.

    Although deformed pipework can be excavated and replaced with modern drains, there is a far less disruptive option. A bullet-shaped re-rounding tool restores pitch fibre drains’ proper shape before they’re cleaned. Then a resin-impregnated polyester textile liner is fitted to strengthen the drains and optimise their performance.

    If you’re worried your property may have pitch fibre drains or you’re experiencing pitch fibre drainage issues, call Mega-Rod today on 01225 422980 for prompt, professional assistance.


    Septic Tank Emptying – Your Questions Answered

    Hundreds of thousands of UK homes, hotels, pubs and other properties send their wastewater to on-site septic systems, consisting of septic tanks and drainage fields. These systems are vital: they ensure wastewater is filtered and cleansed with the aid of gravity and helpful bacteria, so that waste matter is removed and only treated water is […]
    Septic Tank Emptying

    Why Sewer Rats Invade Drains

    You’ll be aware that many residential and commercial areas are plagued by rodents, but have you ever considered the scale of the problem? It may come as a shock to learn that there are approximately 80 million brown rats in the UK. In other words, there are several million more of them here than people. […]
    Sewer Rats

    Looking after Your Septic Tank’s Drainage Field

    If it isn’t practical for your property to be connected to the sewer network, you may well have an on-site septic system, consisting of a septic tank and drainage field (which is also called a drainfield or leach field), instead. This is often the case for Mega-Rod customers in the South Gloucestershire countryside, one of […]
    Septic Tank’s Drainage Field

    The Problem with Pitch Fibre Drains

    Are you responsible for a property that dates back to the mid-20th century or had its drainage system altered during that period? If so, your wastewater could well be flowing through pitch fibre drains – and drainage issues may be present or just around the corner. This problematic pipework was introduced across the UK during […]
    A row of terrace houses in Bath built around 1940

    5 Major Benefits of Professional Drain Cleaning

    If you’re not in the habit of asking a drainage company to carry out professional drain cleaning at your property, it’s worth familiarising yourself with the key advantages of doing so. Some property owners don’t realise that whatever condition their pipework is in, drain cleaning can be beneficial – this kind of service isn’t just […]
    professional drain cleaning improves your drainage system’s performance

    Why You Need an Up-to-Date Drainage Plan

    You know your property’s drains are underground, but do you know their exact location? How far down is the pipework? Can you describe the layout of your drainage system? If you’re struggling to answer one or more of those questions, you’re not alone. The Bristol and Bath drains experts here at Mega-Rod help numerous residential […]
    House Drainage plan

    The Difference between Drain Engineers and Plumbers

    Every property owner will encounter a water-related problem (for example, a nasty odour coming from plugholes or a tap that refuses to turn off) from time to time. Whether you’re faced with this kind of issue at home or work, you’ll want prompt assistance from a professional. The question is who should you call? Is […]
    Rubber ducks in a bath with water problems to be fixed by drain engineers or plumbers

    How Heavy Rain Affects Your Drains

    Across England, drains serving homes and businesses are currently under much greater strain than usual due to heavy rain and flooding. When Storm Henk arrived in early January, it unleashed torrential downpours on vast swathes of the country, becoming the eighth major storm in just three months, as BBC News reports. At the time of […]
    heavy rain and flooding affecting drains

    Do You Need a Homebuyer’s Drain Survey?

    When you’re buying a new home, there are numerous important tasks you need to cross off your to-do list, from exchanging contracts to finding a reliable removal company. With so much else to think about, you could well be tempted to adopt an ‘out of sight, out of mind’ approach to the property’s drainage system […]
    Do you need a Homebuyer’s Drain Survey for your new home?

    Winter Drain Care Advice

    The coldest months – December, January and February – can be a testing time for your property, including your drainage system. This is especially true if you own a period property with ageing drains or your drains were laid in shallow trenches (the minimum depth for a drain is 600mm). However, it must be said […]
    Frozen pipes
    1 2 3
    Request a call back from our team
    Enter your contact details and we'll call you back

      Need your drains unblocking? Septic tank need emptying? Need a CCTV Drain Survey? Contact the experts at Mega-Rod on 01225 422980. We offer a prompt, competitive service from a family firm working in Bath, Bristol and the surrounding area.