Underfloor Heating & Radiators with a Combi Boiler: A Great Idea!

Gaining traction in recent years, is underfloor heating. You may have come across it at luxury hotels or seen it being installed on one of the many home decoration shows on tv. It provides cost effective heating that can really make a home feel cozy in the winter. But is it worth replacing your existing combi boiler with, and what would you do with all those existing radiators? Well, fear not, because you can keep your existing system and power both radiant underfloor heating and radiators from the same comi boiler. Provided you have a suitably powerful combi boiler.

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What Is Underfloor Heating?

Underflooring heating, sometimes called ‘radiant underfloor heating’, works by turning your insulated floor into a giant heat emitter. It uses either flexible water pipes or cables to heat the floor to a low level. It’s suitable for a range of different properties, is energy efficient and allows for zonal heating, meaning you can easily and efficiently heat the areas of your home or property that need it.

Underfloor heating comes in a variety of different systems but broadly speaking we can be split up into two separate groups;

  • Wet UFH Systems (Wet UnderFloor Heating Systems)
  • Dry UFH System (Dry UnderFloor Heating Systems)

They are most often used to replace conventional heating systems but can work well with a combi boiler and radiators, should you choose.

Wet Underfloor Heating

A wet underfloor heating system can be connected to your existing combi boiler and radiator system, the only real qualification is that your boiler needs to be powerful enough. A wet UFH system pushes water through a network of pipes laid in the floor. These pipes use a particular type of flexible material to stop leaks.

Dry / Electric Underfloor Heating

Electric underfloor heating refers to the process of heating the home by using a series of electrical cables or heating mats underneath the floor. These are placed atop an insulated surface to trap the maximum amount of heat and ensure it travels upwards and minimising heat loss.

The Benefits of Underfloor Heating

There are several benefits of underfloor heating that explain the surge in its popularity in recent years.

Energy Efficient

Underfloor heating is energy efficient and helps you save up to 25% on household energy bills. For example, a traditional or conventional radiator needs to operate at 65 degrees Celsius, in order to effectively heat up a room.

By contrast, underfloor heating systems can function effectively at a temperature between 29 and 30 degrees celsius. Not only do they consume less energy but also are lighter on your pocket, saving you from big bills.

Low Maintenance

Underfloor heating is extremely low maintenance leaving you to care about little once you have installed it. Barring a couple of regular check-ups (as with any appliance or electronic device), you don’t have to do much.

Easy Installation

Both electric and wet underfloor heating systems are easy and quick to install. They can be installed in small spaces at a short notice.

Safe and Secure

Underfloor heating is safe and secure. You are spared the hassle of worrying about kids running into sharp edges of the radiators and getting injured in the process. There is no hot heating system waiting to be touched by little hands.

This heating is also safer and maintains optimum air quality in the room. Radiators may sometimes affect the oxygen levels in the room due to high temperatures. Likewise, you are spared from dust being caught in the air cycles, as with radiators.

Compatible with All Floor Covering

If you want to get underfloor heating, you don’t have to change your wall and floor space. Underfloor heating is compatible with all floor types such as tile floor, laminated floor, stone floor, carpeted floor and more.

No Compromise on the Design Element

With underfloor heating, you can free up the wall and floor space taken by radiators thereby getting more avenues to design them as you please.

Design freedom is a great thing to have and you can truly create a space reflective of your personality without worrying about mundane things. Traditional radiators do not give you this degree of freedom and stick out, making designing areas in and around the more difficult.

Comfort and Convenience

With underfloor heating, you can laze around your room wherever you please. This is quite different from times when your home is heated by radiators.

Radiators often lead to cold patches of air in areas their warmth cannot reach but underfloor heating creates consistent heating throughout. It is, therefore, both comfortable and convenient.

Are There Any Downsides to Underfloor Heating?

Though underfloor heating has a number of advantages and perks, someone who is planning to get one must have a holistic view of the system. The downsides to underfloor heating include the following:

Installation Costs

Though we can’t guarantee a standard cost estimation (there ain’t any) because it will depend on the system you go for, underfloor heating is more expensive to install than traditional conventional radiators.

You will also have to factor in the costs of installation i.e. plumbing costs, labour costs, and the likes as you will have to contract the services of a professional.

On average, you can expect to pay almost double the installation costs for underfloor heating as compared to traditional heating.

Installation Times

Though electric underfloor heating is faster than wet underfloor heating, both are quicker than getting radiators installed. This is because certain systems have to be put in place before installing electric heat mats or hydraulic systems.

However, if you are changing the heating system in your home as part of a bigger renovation, this should not be a cause for much concern.

How Much Does Underfloor Heating Cost?

Underfloor heating costs vary wildly depending on your home, existing heating system and the type of UFH system you want to go with.

There is also a difference in the costs between electric and water underfloor heating, the latter being more expensive than the former.

The factors that influence the underfloor heating costs include:

  • The choice of heating system
  • The size of your room
  • The type of building and the condition it is in
  • Labour charges

Dry / Electric Underfloor Heating Costs

Electrical underfloor heating can cost you anything between 75 pounds per square meter if you choose heating pads, or above 100 pounds per meter if you go with more sophisticated individual wiring.

These costs do not include your installation charges and labour cost. You will have to budget for these costs as well.

Wet Underfloor Heating Costs

The benefits that water underfloor heating offers in terms of consistent heating and functioning even at low pressure make it an expensive choice. Be prepared to spend thousands of pounds to get this done from scratch to finish.

How Powerful a Boiler Do I Need for Underfloor Heating?

The power of the boiler you need depends on the size of your home and your usage habits. For example, a single-person household will need a less powerful boiler as opposed to the boiler needs of a family of six.

You should go for one that fits your needs. Going for a more powerful boiler than you need is both a waste of money and energy as you would not be using it to its full efficiency anyway.

There are several ways you can figure that out but getting help from an expert will be a good way to go.

Is Underfloor Heating from a Combi Boiler Feasible?

Having a combi boiler at home should not deter you from getting underfloor heating installed. You need to be flexible and make some adjustments for a smooth installation of underfloor heating in your house but don’t expect any major issues.

You should most definitely connect with a certified engineer who can help you navigate the issues. At most, you will need to get a two-port valve installed to avoid overheating. A certified professional will be able to guide you through this perfectly.

Underfloor Heating Systems, Thermostats & Smart Controls: All You Need to Know

If you are unsure of your schedule and want to control your home’s heating needs at all times, you should consider investing in a good thermostat (millions of people in the UK have already embraced this technology).

This helps you control your central heating through your phone and tablet. A smart thermostat is adept enough to learn from your central heating habits and make those changes in your home automatically.

The best part is that a thermostat is compatible with underfloor heating systems. A thermostat will only make you reap the benefits of underfloor heating more efficiently by offering greater control.

Should I use a boiler with radiant heating or a boiler with underfloor heating?

Underfloor heating connected to a boiler might be more energy efficient than a radiator system. It also frees up wall space while providing more consistent, comfortable heat.

When a radiator is heated to between 60 and 75 degrees Celsius, underfloor heating may typically achieve the same results with just 50 degrees Celsius, allowing the boiler to work in condensing mode. This also implies the boiler will last longer.

Because UFH generates radiant heat rather than convective heat like radiators, it produces a drastically distinct temperature profile. Instead of being carried by convection currents and heating the room from the top down, heat rises from the floor, heating from the ground up. As a result, UFH provides the optimal comfort profile of warm feet and cool head.

Last Updated on November 6, 2021

Frequently Asked Questions

Is underfloor heating healthy?

Underfloor heating is great for your health for several reasons. Primarily, it stops the circulation of dust caused by more traditional heating systems. This is down to it using low heat levels to heat the space. This is great for those who suffer from allergies or respiratory problems.

Can the pipes used in underfloor heating burst?

A leak in one of the underfloor heating pipes is very unlikely due to the materials used and once the concrete screed is set, a burst pipe is almost unheard of.

Most pipes used for this purpose go through stringent quality control, so the chances of them breaking during installation or later on is very low. In fact, these pipes are so resilient that they can stand the test of time for decades.

Can you leave heated floors on all the time?

Yes you can leave heated floors on all the time.  The system should have a yearly service by a registered professional but there’s no reason not to enjoy the benefits of underfloor heating all the time.


Author: Indra Gupta

Indra is an in-house writer with a love of Newcastle United and all things sustainable.

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