Case Study: Underfloor Heating and Ceiling Cooling

Installing domestic hot and cold services with Underfloor Heating and Ceiling Cooling

Already working with Multipipe for the underfloor heating system and domestic hot and cold services for the build, Excelsior Heating Services asked if we could also help with the cooling system, as they had no previous experience in it.

Because it is well insulated and has a lot of glass, one of the challenges was the heating in the building. The client’s consultant wanted to use cooling via the heat pump system, and the original design for the cooling involved using ceiling panels and wall panels. We suggested it would be better to install the system directly into the fabric of the building and plaster it in to give it a true thermal mass.

Project at a glance:

  • Executive home
  • Ground and second floor
  • Combined area 823sqm
  • Domestic hot and cold services
  • UFH heating system throughout
  • Cooling system in ceilings
  • Pumpstations

“After working with Multipipe for this project, it has made us far more confident to move forward on other projects, specifically with cooling. The support I’ve always had through ordering, design, and supply from Multipipe has been amazing.”Matthew Smyth Excelsior Heating Services Ltd

Read the full case study here.

Hot water recirculation system efficiency.

With more homes looking to save energy, many are moving to heat pumps which could see a massive reduction in instantaneous hot water systems (combi boilers)—bringing back the cylinder to your client’s homes. But looking further into a cylinder-based hot water system might have some hidden benefits that your clients might not have considered.

“Heating” hot water

Did you know every time a gas combination boiler has to heat water, the efficiency of the boiler drastically drops whilst generating hot water. This is because you have to push your flame rate in the boiler up, causing it to fall out of the condensing mode. You are dropping the efficiency to as low as 70-80%. A system-style hot water system relies on storing water, removing these peak demands. Match this then to a heat pump, and you can operate four or even five times the input energy.

Reducing water use

This comes down to this article’s point, which is a recirculation loop. By looping the hot water back into the cylinder and pumping this, you can massively decrease water usage, whereas a combi boiler (that cannot really have a secondary loop) has to heat up water, pipes, and heat exchanger, and then send it through the pipes around the house. Then, finally, you get your hot water. This is frustrating to wait that long and can waste as much as 12 litres of water every minute of running. By recirculating, you eliminate this issue by having hot water when you need it (which is also a massive time-saving).

However, a few things to consider to minimise energy loss.

Insulate your system

The larger the system (including the pipes), the more energy you lose to use up the reheat. You can be losing as much as 30w/m on a simple 15mm bit of pipe. Compare this to 7w/m if this was insulated. So make sure both your cylinder and pipework system (both hot water flow and return is insulated as much as possible). Remember, we do pre-insulated pipe to save time!

Install a timer

When you are asleep, the chances are you are not using hot water, so why not install a timer on the secondary pump for your customer? Therefore at night, you are saving the energy you would have lost through the pipe system (even if it is lagged). Why not go even more fancy and hook it in with a PIR sensor, so any time someone is in a WC, the pump turns on…

Type of owner

If you have a larger family that uses hot water daily, a cylinder is for you. However, if you are out most of the day and live on your own, an instantaneous water heater is better for you. So consider the occupier of the house. This is because storing anything (no matter how good the insulation is) does always lose energy. The longer the period the system is not used, the more energy is lost.

As always, if you have any questions, our friendly team is here to help! Give us a call on 01245 227630 or email [email protected].

Secondary Recirculation Systems

Why You Should Use Secondary Recirculation Systems

As houses get bigger and clients demand even more from their installer, one of the biggest issues is delivering hot water quickly and efficiently to the hot water taps. The only way to efficiently do this is by setting up a circulation loop from the cylinder to the tap emanating the dead leg between the two – known as a secondary recirculation system. Although there are no legal requirements to fit one, HSE’s best practice is to deliver 50°C water within 1 minute to a tap; this is for legionnaire control.

How Does a Recirculation System Work?

The idea is you have your primary hot water pipe flowing through your house. Besides this, you have a “secondary recirculation pipe”, which travels beside the hot water primary pipe to the extremities of the system. The secondary pipe taps into the primary to join the two pipes. The cylinder then has a hot water circulation pump (normal heating system pumps will not work). The pump is set to push the water through the primary pipe to the tap, and it then returns on the secondary pipe, thereby keeping your hot water hot all the way to the tap.

Limits of a Secondary System

With 60-70°c water flowing through it for most of the day, the secondary pipe has a hard life. A heating system can flush through the water’s pH and impurities. However, you cannot do this with a recirculation water system. Also, you are transporting oxygenated water, which can harm parts of a system. This is why all plastic pipes made under BS 7291 cannot be used on these systems. However, because of how our pipework is made, MLCP can be used with recirculation systems as Multipipe MLCP is made to a different standard than plastic pipe. See our MLCP range here

Our Top Recommendations for Secondary Recirculation Systems

  • Where possible, insulate as much of the pipe with good quality, thick insulation. This will limit the heat loss going back to the cylinder.
  • Only use a WRAS-approved pump specifically designed for hot water circulation.
  • Fitting a timer to the pump is a great idea for energy efficiency to stop the circulation when not needed.
  • You can use a rule of thumb of 2 sizes smaller than the flow pipe for sizing the right pipe.
  • If you have reduced flow rates at your tap, you might need to fit a flow restrictor on the secondary pipe to push water to the tap.

Towel Rails

Did you know fitting a towel rail on the secondary circuit can be done? This is great because they keep constantly hot! (as long as the timer runs). Ensure you consider the heat loss to your cylinder, but also, they *MUST* be WRAS approved and made of stainless steel or copper. Lastly, the towel rail should only be fitted to the return circuit of the hot water system.

If you have any questions about secondary recirculation systems, please email our technical team who will be happy to help: [email protected].

How MLCP Press-Fit Compares To Plastic Push-Fit

How MLCP Press-Fit Compares To Plastic Push-Fit

When it comes to plumbing solutions, there are many options available on the market. Two popular choices are press-fit and push-fit piping. In our blog, learn how MLCP press-fit compares to plastic push-fit plumbing.

What is MLCP?

Multilayer Composite Pipes (MLCP) is a type of piping that is made up of multiple layers of different materials. The inner layer is typically made of cross-linked polyethylene (PEX), which is a flexible and durable material. The outer layer is made of aluminum, which provides strength and stability to the pipe. The layers are bonded together using a special adhesive, creating a strong and reliable pipe.

Over the last few years, we’ve helped numerous installers to move to MLCP, resulting in faster, cleaner, more secure, and more profitable installations. Find out more about Multipipe’s MLCP here.

What is Push-Fit Piping?

Push-fit piping, also known as push-to-connect or push-fit fittings, is a type of piping that uses a push-fit connection system. This means that the pipes are connected by simply pushing them together, without the need for any tools or adhesives. Push-fit piping is typically made of plastic, such as polyethylene (PE) or polypropylene (PP).

mlcp press-fit

In March 2023, leading insurance company Zurich, shared they were seeing an increasing number of leaks relating solvent-related pipe leaks. One claim involved almost £800,000 worth of damage!

Paul Redington, a Regional Major Loss Manager at Zurich has said: “Plastic pipework is here to stay but Zurich and our forensic experts Hawkins are seeing an increasing number of escape of water losses involving its use. We are concerned that plastic push-fit systems for example require less skill and training to install, and if not fitted-properly can leak, causing significant loss and disruption.”

Now that we’ve covered the basics of MLCP and push-fit piping, let’s take a closer look at how they compare in terms of various factors.

Here’s how MLCP press-fit compares to plastic push-fit plumbing:

Secondary Circulation Systems

Any pipe manufacturer under BS7291 that covers all plastic push-fit ranges is not suitable for a secondary recirculation system and, if fitted, can cause leaks, and at worse can lead to full bore detachments causing serious leaks and damage. The pipe manufacturers for these pipes will not cover your system if it is used on this type of water.

However, because of how our pipework is made, MLCP can be used with recirculation systems as Multipipe MLCP is made to a different standard than plastic pipe. Find out more about secondary recirculation systems here.


Plastic push-fit, as you will know, is very widely available. The ease of application is often seen as an advantage; no specialist tooling other than a cheap pipe cutter is needed to make a joint. However, we see this as deskilling of the plumbing industry and potentially harmful, as this can lead to issues in water hygiene like Legionnaires’ disease.

In fact, there are no laws stopping any general public from purchasing the material to do their own plumbing. Which when you consider insurance companies are reporting the highest level of water escape, this could become a harmful and costly problem.

MLC helps by ensuring specialist tooling is required, and Multipipe would only sell our products to the plumbing and heating trade, trying where we can to regulate this unregulated industry. This is why we can offer a 25-year insurance back warranty with our products.

Full Bore Detachment

Because plastic push-fit relies on fitment on the outside using a grab ring that “bites into the pipe”, if anything happens to the outer layer, the fitting can slip and has been known to lead to a full detachment of the fitting. This can lead to over 10 litres per minute of water entering the property, which very quickly can lead to irreversible damage.

Multipipe’s press-fit system has been manufactured to the highest quality with multiple safety points, including leak path before the press, and inspection windows. This ensures when pressed, you will have decades of leak-free issues.

More Secure Fittings

Compared to traditional push-fit piping, MLCP secure fittings can’t be knocked or blown off. This extra security not only benefits your customer, who will get to enjoy their new plumbing with greater assurance about its quality and longevity, but can also benefit you as the installer. You will spend less time having to explain why fittings and joints have come loose and repairing these joints, meaning your workmanship won’t be questioned by customers and your brand will be seen as a more professional and quality driven.


Once bent, MLCP completely keeps its shape, lessening the need for fastening points in comparison to push-fit piping. Again, this leads to a reduction in installation time. But what you are really saving is money. With less need for fastening points, you won’t have to buy as many fittings to complete the installation, increasing the efficiency of both yours, and your client’s budget.

Low Heat Expansion

Some push-fit systems expand 8 times more than MLC at normal system temperatures, meaning the pipework can move after installation causing noise and stress on the fitting.

Thanks to the specialist technology used to create the temperature resistant PE-RT, MLCP has a low heat expansion, performing comparatively to that of metal piping with the advantages of versatile plastic pipe. The low heat expansion makes MLCP incredibly durable – so much so that we give it a 25-year guarantee, with 50 years upon application.

Sealed For Hygiene

Most push-fit systems seal with an O-ring on the outside of the pipe, which under normal site conditions can get damaged or dirty.

Multipipe’s MLCP is sealed from inside the pipe, making it far more resistant to damage and reducing the potential for leaks in the system. WRAS approved, MLCP is ideal for transporting drinking water hygienically, making it a popular choice for health industry applications such as hospitals.


In conclusion, while traditional products are good enough for the job, you want to stand out amongst your competition. Using the best, most innovative products will ensure that you are able to complete jobs quickly and efficiently.

At Multipipe, we care passionately about raising UK plumbers’ operational standards and our societies’ perception of the trade. That’s why we supply quality products like MLCP.

To find out more about MLCP, click HERE. If you’re interested in purchasing MLCP or training on our systems, email our sales team on [email protected] or call our friendly team on 01245 227630.