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MDPE (Medium Density Polyethylene) pipes are commonly used in the drainage industry due to their durability, strength, and flexibility. These pipes come in a range of colours, each of which serves a specific purpose. In this blog, we will explore the different colours of MDPE pipes used in the drainage industry and their applications.

Blue MDPE Pipe:

Blue MDPE pipes are commonly used for carrying potable water. The blue colour indicates that the pipe is suitable for carrying water that is safe for human consumption. These pipes are often used in water treatment plants, water distribution networks and in domestic plumbing applications.

Black MDPE Pipe:

Black MDPE pipes are used for non-potable water applications, such as irrigation and industrial water supply. The black colour of the pipe helps to prevent the growth of algae and other microorganisms, making it a suitable choice for use in outdoor environments.

Yellow MDPE Pipe:

Yellow MDPE pipes are used for gas distribution. The yellow colour indicates that the pipe is suitable for carrying natural gas or LPG (liquefied petroleum gas). These pipes are often used in gas distribution networks, industrial applications and in domestic gas supply systems. In conclusion, MDPE pipes are available in a range of colours, each of which serves a specific purpose in the drainage industry. By understanding the different colours and their applications, it is possible to select the right pipe for a particular application, ensuring that it is safe, efficient, and effective

Different types of drainage systems

There are two category types of drainage categories, one being foul water and one being surface water. Any contaminated water from your bathroom, kitchen, or utility room is considered foul water and is always directed to a foul water drain. However, surface water drainage

Most properties either have older drainage systems or combined drainage systems, that directs precipitation to the dirty drain through a series of gully traps to keep bad odors from escaping the drain.

However, the two drainage systems are kept apart in modern homes and systems, and rainfall is either drained into a soakaway, a watercourse, or a surface water sewer. A soakaway is typically nothing more than a hole in the ground that has been backfilled with coarse stone, allowing surface water to percolate back into the ground.

Installing your drainage system

You should always make sure that you communicate with the Building Control Department at your local Council, regardless of whether you are installing a new drainage system or intend to make changes to an existing drainage network. You must provide blueprints that specify the range of the work to be done, making sure that the work complies with the most recent Building Regulations because, in essence, the job will need to be passed off and inspected thereafter. On the other hand, if you are simply replacing broken pieces, notification is not required.

Underground drainage

All drainage pipes and underground drainage fittings should be Terracotta in colour to ensure compliance with the Building Regulations and prevent the works from having to be rejected by the Building Control Department.

How to install your underground drainage systems?

A network of flexible plastic pipes, inspection chambers, rodding points to clear any clogs, and access fittings make up modern underground drainage systems.

It is crucial that there be appropriate cover of at least 600mm because such materials are prone to distortion under load. The material used as the cover’s backfill should permit percolation; often, pea shingle or another granular form of stone is utilised.

Trenches can be built by hand although a small excavator or micro digger is usually preferred. Building regulations should be followed, and anything deeper than 1,200 mm must always be supported or shored up. The sides should ideally be dug at an angle of repose to reduce the risk of the excavated material collapsing in on itself and causing significant damage or death.

Use a hacksaw and mitre block to precisely measure the drainage pipes’ dimensions and cut them to fit. The freshly cut pipe will have rough edges after being cut, therefore the surplus burrs need to be removed and the edges need to be chamfered at a 45-degree angle with a wood file. Using a cloth to wipe the pipe should be sufficient.

It is simple to connect underground drainage pipes and the fittings that accompany them, but the male and female ends of each component must be lubricated to fit together. They ought should slot together rather easily after being greased.

Surface Water Drainage

Channel drains are a typical building material that are employed globally for several applications. They may also be referred to as linear drains or trench drains. But how do drainage channels work?

Unlike gullies, which only drain water from one point along their length, linear drainage systems do so continuously. They consist of a closed channel with a grating of some kind on top.

A channel drain’ fundamental function is to remove surface water from a specific area. They should never be placed uphill, but rather at a location where surface water is likely to roll towards.

To Find out more about Channel Drainage, visit our sister website www.polychannel.co.uk or alternatively if you want to read more on the installation process of channel drainage check out our blog post ‘How to install Channel Drain’


To shop our underground drainage products, why not click here. Or for any more information surrounding our underground drainage pipes drop us an email at sales@polydrianage.co.uk

Maintenance on your manhole cover is extremely important, even there is a small issue with your manhole now is the time to fix it, by replacing it. Even a small crack in the middle of the manhole can be extremely dangerous, especially in areas where there are pedestrians and small children stepping over it, as it has an increased risk of falling through. Either way, no matter the damage, a replacement manhole cover is required.

Replace your manhole cover using the steps below…

Firstly, you need to take an accurate measurement of the manhole cover you currently have installed. To do so, you need to get a clear measurement, this is the width, height and depth of the hole in the ground. To get yourself a clear measurement of the opening, take your tape measure and measure the inside of the inspection chamber from wall to wall. It is suggested that every manhole is measures this way and this will allow you to find the exact replacement.

Measuring replacement manhole cover

If your manhole cover does have an inspection chamber underneath then it is imperative that you measure the diameter of the circular chamber, so that you can ensure your manhole cover matches. We would also suggest that when purchasing the replacement manhole, you check to see whether the cover and frame selected is compatible with all the main inspection chambers brands.

Secondly, you need to pick your load class. Every manhole is designed to sit within a specific load class, which allows you to understand the maximum weight the manhole can safely take. E.g., if a manhole cover is to be installed in a shopping center car park, then you can safely say that you would need a manhole cover that can withstand a C250 loading.  This to ensure that the manhole continues to perform correctly when cars are moving over it.

Below shows a break down of the different load classes suitable for manholes.

Choosing your materials, here at PolyDrainage we specialise in Ductile Iron and Composite. Choosing the material is totally up to you, However, below shows the benefits of each material.

Ductile Iron Benefits:

Composite Benefits:


For any more information surrounding changing and maintaining your manhole cover, please do not hesitate to get in touch with us at sales@polydrainage.co.uk

Inspection chambers are points of entry to underground piping that enable maintenance and obstruction clearance. There is a very high likelihood that you will need to create an inspection chamber when installing any kind of subterranean drainage. Manholes and inspection chambers serve similar purposes, with the exception that manholes permit physical entry while inspection chambers are exclusively used for cameras and equipment.

Where should you install it?

Every time a branch pipe connects to a main drainage run, inspection chambers ought to be put in. This will make it simple to access ongoing drainage channels without using a lot of drain rods. Additionally, it minimises the distance that any inspection cameras must cover. Install another inspection chamber there whenever a drainpipe changes direction by more than 30 degrees or when a straight drainpipe run is longer than 20 meters.

Installing sufficient inspection chambers throughout the drainage system will ensure that every component is reachable with a drain rod, according to the general rule of thumb.


 What are inspection chambers made from?

Some manufacturers of inspection chambers provide the components as a whole system, while other manufacturers demand that you purchase each component separately. Inspection chambers are made up of three parts: a base, a riser, and a lid. Rubber seals between components hold the inspection chamber’s components together.

The cover…

An inspection chamber’s cover is often made of plastic, protecting it from tampering and unauthorised entry. For safety reasons, it also conceals the hole in the ground. To comply with standards for installation in driveways, parking lots, and other heavily used areas, covers for inspection chambers are available in a variety of weight load classes and come in both round and square shapes.

The Riser…

The middle part of the system, which comes in a variety of heights, is called a riser in an inspection chamber. The inspection chamber cover rests comfortably at the surface thanks to the riser’s addition of just the correct amount of height, which is attached to the base by rubber seals. These have corrugated exteriors that can be cut with a saw to facilitate this process.

The Base…

Naturally, the element at the “bottom” that is closest to the drainpipes is an inspection chamber base. A base can accommodate pipes with a diameter of 110mm or 160mm thanks to a variety of inlets. There are various bases with various inlet counts available for purchase. Use a blanking plug if you have more inlets than pipes.

The installation…

The middle part of the system, which comes in a variety of heights, is called a riser in an inspection chamber. The inspection chamber cover rests comfortably at the surface thanks to the riser’s addition of just the correct amount of height, which is attached to the base by rubber seals. These have corrugated exteriors that can be cut with a saw to facilitate this process.

To view our range of inspection covers, chamber risers and chamber bases, click here.


For specialised purposes, non-standard sizes inspection chambers. Or even some more information surrounding inspection chambers. Get in touch with us at sales@polydrainage.co.uk

Introducing our new Jumbo Grease traps supplied to us by Turtle Enviro. Designed to enhance and improve the performance against fats, oils, and greases.

A grease trap is most commonly used in commercial kitchens and smaller scale restaurants to ensure that they can meet the requirement of all relevant legislations. The Jumbo grease trap has been designed to meet both building regulations Part H and BS EN 1825 the British standard for all grease traps and separators.

The Jumbo grease trap is an underground, fat, oil, and grease interceptor created to operate passively. Simply stopping the flow of wastewater and allowing it to cool and separate into three layers inside the interceptor—FOGs, solids, and water—is how passive designs function.

FOGs (Fats, Oils, and Greases) float to the top of the water because they have a specific gravity that is lower than that of water, which causes them to separate from the water as wastewater enters the unit. All passive grease traps/interceptors operate on the principle of “Gravity Separation,” which is a tested design.

Solids and food waste, which are heavier, will fall to the unit’s base as the FOGs build a “grease layer” at the top. By using the hollow baffle and step to define a flow path inside the unit and, in addition, the moulded step, which enables better settlement and enhanced storage of solids and sludge, the Jumbo’s patented design improves this separation process.

Our Jumbo grease trap is now 22% deeper than the previous model, increasing the working volume to 340 litres, converting the unit to a Nominal size 1 and providing 20% additional solids storage due to an increased step height.


For any more information on our new Grease Traps, supplied by Turtle Envrio please visitour website at www.polydrainage.co.uk.

Underground drainage pipes play a crucial role in keeping our homes and surrounding areas safe from flooding and water damage. Connecting these pipes properly is essential to ensure efficient water flow and prevent any potential blockages. In this blog, we will discuss how to connect underground drainage pipes and the equipment required to do so.

Step 1: Determine the Pipe Size and Direction

Before you start connecting underground drainage pipes, you need to determine the pipe size and direction. The size of the pipe will determine the type of connector or coupler you will need to use. The direction of the flow will determine the slope of the pipes and where the connection should be made.

Step 2: Cut the Pipes to Size

Using a saw or pipe cutter, cut the pipes to the required size. Ensure that the cuts are straight and clean to prevent any leaks or blockages.

Step 3: Clean the Pipes

Before connecting the pipes, make sure that they are clean and free from any debris or dirt. This will ensure that there are no obstructions in the flow of water.

Step 4: Attach the Couplers

Using the appropriate couplers or connectors, to attach the pipes together. Make sure that the couplers fit snugly and are securely attached. Depending on the type of coupler, you may need to use a rubber seal or adhesive to prevent leaks.

Step 5: Use a Level to Check the Slope

To ensure proper water flow, it is important to check the slope of the pipes. Use a level to make sure that the pipes have a gradual slope and are not level or sloping in the wrong direction.

Step 6: Cover the Pipes

Once the pipes are connected and the slope is checked, cover the pipes with soil or gravel. This will protect the pipes from any damage and help to blend them into the surrounding area.

Equipment Required:

In conclusion, connecting underground drainage pipes is an important task that requires proper planning and equipment. By following the steps outlined above, you can ensure that your pipes are connected properly and efficiently. It is also important to regularly check and maintain your drainage system to prevent any blockages or damage.


For any more information on our new Grease Traps, supplied by Turtle Envrio please visitour website at www.polydrainage.co.uk.

Ducting coil is used to guarantee that pipes and cables are shielded against external forces, which may interfere with how the cables should operate. 

Ductwork indicates to an installer that there are significant subsurface drainage pipes or services present, suggesting that it will be left alone or simple to repair if necessary. So, it is crucial that the installation is completed to a high degree because it simplifies subsequent tasks and guarantees that whatever is travelling through the duct itself may function as intended.

Top Tip**

The most crucial thing is to make sure ducting is done correctly. We are here to help and give you everything you need to know regarding ducting coil, including legal requirements surrounding the procedure, the installation process, as well as all the do & don’ts for ducting coils. 

What colour should you use?

Before you start any job, which included ducting it is extremely vital that you get the fundaments correct before you begin. The equipment needed for your project will be determined by the cables/ wires passing through and what they are used for. This is due to the fact that it is that it is legal requirement in the UK.

Ground workers can adopt the appropriate approach when there is construction going on around them since the colour of the pipes help them identify what is passing through the ducting.

Below highlights the correct colours used during ducting installation:

Orange – Used for street lighting/ traffic light signals.

Green – Used for the protection or any CCTV cables or fibre optic materials.

Blue – Used for water mains.

Black – Used to protect electricals.

Yellow – Used for gas.

Ducting Coils Colours Explained

How to decide which material is the right one for your project.

When deciding which material is best for you, we always advise speaking with a utility specialist. Nonetheless, there are a few broad guidelines you can adhere to that are generally accept.

The black electrical cable duct pipe x 6m is an excellent choice for short-distance duct installation because it is composed of high-density polyethylene. These six-meter lengths can be the best option for you because they are simpler to handle across short distances than the coils, which might make life more challenging because they are 25- or 50-meter coils. The most common length for cables is six metres.

The flexible coils (25m/50m) are useful for installations across extended distances. Flexible coils are frequently needed for installing electric cable to buildings. Moreover, they are available in Twinwall HDPE coils (high density polyethylene). This basically means that the ducting can handle abrupt changes in angles because of its improved flexibility while completing specific ducting installations in non-standard locations. The structure and strength of the ducting are improved by using polyethylene for both the smooth inner wall and the ridged outer wall, which maintains the ability of ordinary pipes to be dragged through by wires and pipes. Therefore, avoid the typical error of purchasing bends that are too rigid for the pipe and the terrain you are traversing will increase project duration.

When do you need to use extra strength ducting?

We recommend trying a stronger ducting pipe when the duct will be supporting a utility pipe in an area that needs to sustain significant loads. For instance, you would choose a higher resistance form of ducting if you had to run a specific type of MDPE pipe underneath a road. The enhanced strength types of ducting are only created to meet the required load rating; no specific material is employed in their construction.

When selecting the proper ducting to house your electrical wires, there is a little more to consider since it must be excellent enough to match the legal quality standards in existence. It is crucial that the ducting complies with BS EN 61386 and the 12–24 classes established by Energy Network Association Technical Specification if the electric cables are being run underground (ENATS).

The key information that you should be aware of prior to installing your electrical ducting is covered in both blog posts.  There are three main class types of ducting that you should be aware of, and this is one of the most crucial lessons that can be learned from both. Class 3 ducting is the most often used because it is made for everyday use, while class 1 ducting is used for high voltage cables and class 2 for low voltage purposes.

Don’t give in to the temptation to choose ducting if you are ever unclear about what is required. This will only produce negative outcomes. You can get in touch with us, and we’ll try to assist you. To lessen the chance of causing a hazard or breaking the law, we strongly advise that you consult a specialist.

Following the ducting guidelines.

To ensure you follow the guidelines correctly it is crucial that you seek the assistance needed if you are struggling to understand anything. Whenever, you are unsure or lack the ability to install specific types of ducting, you can use other government-written materials are available. As well as this we can ensure that you will be able to find other multiple online resources. By doing the correct research will ensure that you are completing the project correctly, as well as abiding by the rules and legalisations surrounding ducting.

Where will your ducting be positioned?

Know you fully understand the importance of ducting colour codes, you need to know where it will be going. The ground you are excavating almost always has old ducting with cables or pipes running through it, so you will need to examine it before you dig. Before you start installing anything, you can easily verify this by looking at the project blueprints and with an onsite expert. From here, you can securely determine where not to dig and make an informed decision about where your ducting will rest.

According to government standards, it is ideal to install the ducting so that it matches the layout of the existing roadways and paths. By reducing the number of black electrical ducting bends required as much as feasible, you can lower the project’s overall cost. It is advised that you offer a general notion of where you want your ducting to go by laying it out on the ground before making a final decision.

Laying lengthy radius bends for the straight duct and access chambers for the variations in angles is a wise measure to take to guarantee that you are aware of the parts you will undoubtedly need for your ducting installation. This creates an individual model that you can physically inspect and look at, enabling you to completely evaluate whether your plans are true. Make sure to account for the space needed for the necessary bends if you are installing your ducts using a flexible coil.

This is a fantastic approach to begin to visualise the project. So, it’s crucial that you utilise the appropriate ducting for the job. So, you would normally choose one of the flexible ducting pipe coils if you needed ducting with a little more give.

Our coils are the best option for underground use because they are light but durable and have an integrated draw cord. They also come in big coils to aid with lengthy distances. While utilising solid twin wall duct, keep in mind that it comes in six-meter lengths, is designed to be hard, and has less flexibility than the coils that are most frequently used. They are primarily utilised to decrease the amount of bends in a system and have less airflow resistance than flexible coils, which results in a higher capacity. Ducting is unique in that it is designed to be utilised in circumstances when a little bit extra sturdiness and dependability are needed. To ensure that the flow is not impeded in any way, the interior of the ducting is still smooth.

Before proceeding with the process, make sure you clearly understand the kind of ducting you require and how it will be applied. Don’t forget to mark off this area.

How to keep safe during your project

When beginning any project that calls for the use of resources like gas, electricity, or water, you must be certain that you are approaching it safely. Taking a closer look at this, you must turn off all utilities, including the supply to them, before you begin working. This is due to the possibility that, in the worst-case situation, you may cause fatal injury by working or encountering something that was live. Dealing with Ducting especially in the installation process should be done with vast caution. 

First things first, you must dig your trench. Don’t forget there will most likely already be ducting buried in the ground. Therefore, it is vital that you keep a close eye on specific things when undertaking your project.

One thing you should always be wary about when digging in areas where there may be old pipes, is that they may not have warning tape or indicators identifying the type of material it is constructed out of or what it was used for. We would advise to proceed with caution when faced with issues like this as the pipes will be old and the regulations that where in effect at the time of installation will now be out dated. We would also recommend you to be aware that the colour may not be the most accurate indication of what the pipe is or was used for because older pipes may also be discoloured because of the extended periods they have been buried for.

Again, if you are unsure of anything when digging a new trench and being face with older pipe work and discoloured ducting, we recommend that to seek advice from a professional.

However, on the other hand if everything goes smoothly and you stick to the path you had planned for your pipe, you should have a lovely trench for your ducting to fit into. To create a protective bend for the ducting to sit in, it is occasionally required to add a layer of grit sand at the bottom of the trench that is about 45 to 50 mm thick. It’s time to install the ducting after the trench has been established!

Getting started with the installation process…

The last thing you want to happen when installing the ducting is to lay the coil only to discover that it is damaged, so we advise performing a fast inspection of the coil before moving forward with the procedure. If everything checks out, you should be ready to start your project.

The next phase is simply to begin inserting your ducting into the trenches you have made. The last thing you want is to lay your lengths or coils of black Twinwall duct and then discover that you don’t have the proper twin wall or seals. So be sure you are using the right couplers and seals.

In addition, using a draw cord with your twin wall is crucial if you want to make threading cables through the ducting as simple as possible. To spare you the time and inconvenience of having to do it yourself, many of our coils already have the threaded cord inside of them. If this isn’t the case, though, make sure you have some anyhow to give yourself the peace of mind that everything will be ready when the wires need to be threaded through the ducting.

We advise getting a piece of fabric that fits the width of your pipe without hindering its ability to be pulled through, then attaching the draw cord. This will help you get the cord through the ducting. You can even use a hoover with tape to attach top the other end of the pipe,  and after using the using the hoover for a little while the draw cord should extend there. After that you would be required to hook your wires to the draw cord that has already been threaded through the ducting and use the other end to assist in pulling the cord through the ducting. You are one step closer to finishing the project now that cables are running through your ducting.

Finally, once everything is in place, all ducting installations should be double-checked. While running electrical products via the ducting, such as cables, the seals and points of connection are always the most important things to verify. This is since moisture will alter electrical components if it enters the system, which could turn into a safety problem. However, if everything is in order and you are satisfied with the ducting in general and the sealing points, it is now time to apply the tape and lay the backfill.

Backfilling in detail

When you backfill, you are reusing or replacing what has been dug up. Covering the actual ductwork with 150mm of sand is standard practise in the sector. Because the sand will act as a barrier, this can prevent the duct from being harmed by any piercing instruments. From here, you can add more soil, or another backfill of your choice to replace the remaining space.

You must first make a warning of what is underneath before you can finish off anything, and that is where the warning tape comes in. Because there are so many various types of ducting and tape, it is important to make certain that the type of warning tape you choose corresponds to the type of ducting you are using. Before backfilling the remaining space, the tape must run the complete length of the duct.

To view our range of warning tape here – ‘Click here’

Once you have marked your ducting correctly and completed the backfill your project is complete. If you have any further questions about any of our products, don’t hesitate to contact us!

Underground drainage pipes, Ducting coils, and MDPE are just some of the drainage pipes supplied at PolyDrainage. To make it easier for our customers we split them up into separate categories by pipe diameter, price, and application.  

EN1401 Drainage pipes –

Supplied by MagnaPlast we offer a huge range of underground drainage pipes and fittings in 110mm & 160mm diameters.

These lightweight soil pipes and manufactured from PVC-U, allowing for strength and durability. As well as this, it creates a manageable product, suitable for high-temperature waste discharges.

To Shop our range of EN1401 Drainage pipes & accessories click here

MDPE Pipe –

Here at PolyDrainage, we supply MDPE pipe coils in a variety of different sizes in blue, black, and yellow. Our MDPE has been designed for maximum jointing integrity and is the ideal solution for new installations, pipeline replacements, and rehabilitation.

MDPE is quick and easy to install, and they can be supplied in longer lengths,  reducing the number of joints required in the system, and are a cost-effective alternative to concrete or metallic pipelines.

To shop our range of MDPE pipe & accessories, click here.

Ducting Coils

Underground ducting coils are used to protect any essential utilities, used for buildings in domestic or commercial areas.  These utilities range from gas, water, electricity, phone lines and internet.

Our ducting coils are stocked in 63mm & 110mm diameters. 

Below is a breakdown of the ducting coils available at PolyDrainage, and what they can be used for…

Orange Ducting

Used to protect cables streetlights and traffic signals. 

Blue Ducting

Used to protect Water service pipes. 

Green Ducting

Used to protect any cables/ wires linked to CCTV. 

Yellow Ducting

Used to protect and cover any gas lines. 

Black Ducting

Used to protect and cover any cables linked to electricity.

To shop our range of Ducting coils & accessories, click here.

Ducting Coils

If you would like to receive any extra information surrounding our drainage pipes, you can an email at sales@polydrainage.co.uk