The ‘best’ heating system This article is sponsored by LimeStop
The latest census data tell us that 74% of households in Britain are using gas, while
9% are electric. Less than 1% are heated by ‘renewable’ energy (such as heat pumps,
etc.) with most of them in West Wales, Cornwall, and East Anglia. The conventional
‘boiler’n’radiators remains the most common type of heating. If the government have
their way, this is going to change - and that transition isn’t going to be cheap!
But if you would rather have a great heating system to keep you and your family warm,
then money, although a factor, shouldn’t be top of your concerns. How about reliability?
What about convenience and control?
Let’s be clear from the start. Saying the ‘best’ heating is like saying, what’s the
best car? The best is going to be determined by how much you would be willing to
pay. For example, most heating systems are controlled by a single air thermostat
fitted to a hallway wall (or maybe each radiator has its own thermostat - though
these can be fairly inaccurate). So any really good heating system is going to be
one that does away with a central thermostat, and instead regulates each room not
just by temperature, but by time. This means a good quality (accurate) air thermostat
in every room - controlling the temperature that you set - but also timed, so that
you can use it according to your needs. In a 12-room house, at £50 a go, that means
you would spend £600 on air thermostats alone - before you even decide what type
of heating you want. That’s a hefty amount - but necessary for a really good heating
system, one which responds to your needs.
So our first requirement is individual time and temperature controlled rooms. We’re
on our way towards the best heating system (money being little object). For this
assessment, we’re going to assume a room that is 3 metres by 3 metres, so 9 square
metres - with a heat requirement of no more than 1.5kW.
Okay, so what about exactly how that warming of the air (in the rooms) is achieved?
Traditionally in Britain, this has been provided by radiators. These are heavy lumps
of metal, containing hot water which is heated by a boiler (traditionally gas).
The water gives up its heat to the room, and a pump (usually fitted inside the boiler)
brings the water back to the boiler to be re-heated. This is what a typical British
heating system is. It’s very basic, and very old. Quite why it’s been so popular
is because it’s basically all that heating ‘engineers’ (actually, technicians) know
how to do. If they have served any apprenticeship or training, heating by radiators
would have been drilled into them - and heating technicians are a conservative lot,
they don’t like the idea of trying anything new (though that is changing). This has
been the reason why heating hasn’t really moved on. Ask your installer for a quote
to install a heating system, and 9 times out of 10 he will suggest radiators and
a boiler! How very 1960s? When looking for a heating system, consumers really should
employ the services of a heating consultant (not an architect!). Alas, many just
ask their plumber...who will favour radiators, as it’s all he knows. Builders (developers)
are no better. Look at most new housing developments in the very recent past, and
you may see a lovely showhome...with radiators!
Where’s the vision, the progression? Trouble is, most developers are still building
homes which look as though they were constructed in the 1940s. So what do you NOT
We will rule out radiator heating right now. Radiators are unattractive, and rely
on a system of water pipes which can leak, and they are prone to magnetite-sludge
and bacterial growth in the water! We should say at this point that ‘radiators’ don’t
just radiate heat, they also provide convected heat - warmed air which gets moved
by the air currents within a room. That’s not to say there isn’t an argument for
gas boilers, there is; but not radiators! If you must go for a gas boiler, then an
obvious system is wet underfloor heating - as it lends itself so well to all heat
generators: gas boilers, electric boilers, and heat pumps.
Some years back, underfloor heating (UFH) became a choice. The first UFH systems
were electric, and installed in council flats - because boilers weren’t an option.
They were awful, and gave UFH a poor name for many years. It wasn’t until the advent
of water pipes within the floor (still heated by a boiler, though!) that UFH made
a comeback. Around the same time, electric UFH using large mats (like Warmup Foil)
also made an entrance to the heating market. This was finally a choice! Though many
installers ignored it, some were adventurous, and some even began installing only
Advances in UFH systems have meant that some can be set into the floor, some can
be installed on top of an existing floor, and some are the floor itself. Some are
incredibly thin, meaning that they raise floor height by only the size of a coin.
Of course, electric UFH need not raise the floor height hardly at all, and although
many people rule out electric UFH because of the perceived running costs, they forget
that there is zero maintenance to an electric system such as electric warming mats.
Such mats work for very many years without need of any expense. A gas boiler and
radiators in competition with such a heating system would require servicing and parts
replacements, and/or insurance. So that cost must be factored in. This is something
widely ignored, and yet crucial to any investigation of costs, as we will come back
UFH isn’t widely recognised for what it is. It is a large radiator fitted horizontally.
Although your white steel radiator on the wall might be radiating heat to occupants
of a room, when you heat the whole floor, that entire area is radiating heat. For
this reason, UFH can run at a lower air temperature than a conventional system. Whereas
you might heat the air in your room to 21° C with a gas boiler and radiators, a UFH
can easily get away with heating the room’s air to only around 19° C for the same
Your feet are warm, and the warm air currents perform in such a way as to make you
feel comfortable at a lower temperature. It’s convenient that it is this way, because
each square metre of your heated flooring can only emit so much heat - let’s say
140 watts (for electric matting). For our typical room, that’s only 1.26 kilowatts
of heat being emitted by your UFH. A radiator system would likely be 2 kilowatts.
So your UFH is providing the same comfort warmth while emitting only a little over
half of what a radiator might give out. The reason electric-matting UFH cannot emit
much more than 140 watts per square metre is because of two factors: one is your
choice of flooring. Many laminated wood floors cannot cope with anything much above
this temperature without being harmed. Secondly, much more than 140 watts per square
metre starts to feel uncomfortably warm on your feet.
Very often, UFH is retrofitted using an ‘overlay’ system. This is laid on your existing
subfloor. However, it’s important at this stage to reveal a rather big problem with
‘overlay’ UFH which is under-reported. Wet overlay UFH (using pipes) has a poor output
of heat. A normal output would be just 80 watts per square metre. That’s a heat output
for our imaginary room of just 720 watts - hardly enough! The fabric of the room
would have to be very well insulated, or the heating would have to be left on permanently
(which is what some people with UFH do). It is possible to get 120 watts per square
metre output. This is just over 1 kilowatt total output for our room. Obviously,
electric matting at 140 watts per square metre is far better. You should be aiming
for a floor temperature of 27°c.
So, the ideal is a room which is insulated enough that it only needs 140 watts per
square metre, or even less. This then, on a 12 room house, might be a heat requirement
(or provision) of around 15 kilowatts. If electricity (for this calculation) cost
30p per kWh, then that’s a cost of £4.50 for each hour that the house heating is
running full on. In reality, of course, the room thermostats would be cutting in
and out. £4.50 per hour does sound a lot (and is!), but heating isn’t about saving
you money, it’s about making and keeping you warm. If a gas boiler instead supplied
water to a loop of pipes under your floor, then you could slash this cost by perhaps
two thirds. BUT...a gas system requires parts, servicing, and/or insurance, as we’ve
already said. So ensure that you factor this in. A gas boiler would also have to
be replaced after 15 years. At a cost of £2,000 that’s a yearly cost of £133 which
you have to also factor in (for its replacement).
So as we can see, we’re leaning towards a UFH system as our ‘best’ system...but we’re
not there, yet.
There are many heating system types, and one which is hugely overlooked is ‘trench’
heating. These are grilles covering a ‘cassette’ heating trench. Inside, either an
electric element or a loop of piping emits its heat (usually) utilising a small fan.
Such a system means that there are no radiators on the walls, and you can do whatever
you want with your flooring - such as lush, thick carpets. They are a little expensive
for what they are, but they have advantages over other types of heating. The only
disadvantage is a very slight noise from the fans. However, there are units without
fans - even electric units without fans, and trench heating should therefore be strongly
considered. For our typical 9 square metre room, the cost would be a little less
than a £1,000.
There exists a second way of using warmed air, and this is within Heating Recovery
Ventilation and straight forward ducted air heating (without ventilation). Although
almost exclusively electric, it is another strong consideration for the best heating
system. With a ‘passive’ home construction - one in which insulation and heat loss
has been taken to the maximum consideration - it is necessary to have a ventilation
system because the house is so air tight.
Stale air is removed, and the heat within that air is exchanged to fresh air coming
in. This is usually around one complete air change per hour for a healthy home. A
simple in-line heater can be added to the ventilation system to warm the air entering
the rooms. It only gets a little complicated when control of the temperatures within
those rooms is considered. Some form of shut-off of the electric heater must be incorporated,
or shut off of the air to the room. This, however, would mean that the room isn’t
being ventilated, as well as not being warmed. If ventilation is not a concern, and
you simply want heating, then there is a lot to be said for this system, and if you
have a loftspace then installation is very easy. The only downsides are that each
heater has to be controlled (so a level of complexity) and the fans do have to be
cleaned every year.
Each room has two grilles in the ceiling - one of which is blowing warm air in, and
the other taking cooler air back out to the heater - controlled by an air thermostat
(one in each room). Such a system may even lend itself to serving ground floor heating,
as the ducting can simply be laid between the upper floor joists - though remember
that you would have to get at the heater or fan if it fails! This form of heating
is more popular in the US, though they tend to have their grilles in the floor. This
may be a better system for distribution of warmed air, rather than ceiling grilles.
Ducted air heating is a relatively cheap system to install. It requires some maintenance
and is very reliable. If you have a bungalow, then it is a serious contender for
the ‘best’ heating system...but bear in mind that control isn’t simple. The heaters
have to be protected from fan failure, etc.
There is also a fairly new kid on the block in the form of infrared heating. These
are being promoted as somehow ‘green’ as they attempt to warm you and not the room.
However, they are still a ‘radiator’ - it’s just they don’t look like one. Indeed,
you can have a picture on your wall acting as an infrared heater.
One downside to infrared heating is the cost - for what they are. To provide room
heat (or rather to the people within the room), our typical room will require two
infrared panels costing around £800 to £1,000. That feels a lot for what is just
a panel, and almost twice the cost of a conventional gas boiler & radiator system
- which would give you hot water as well. But perhaps the biggest concern is that
the air within the room isn’t actually heated, so can feel cool upon entering. This
is used as its ‘green’ potential, but we have grown accustomed to warm air within
our homes - even if some of that is wasteful. Heating is, after all, ALL about comfort.
A heating system isn’t there to save you money, it’s to provide comfort warmth -
that’s ALL its job is! So with two large factors against it (cost and lack of warmed
air), infrared heating probably won’t give you the best heating system.
So apart from ducted air heating (may not be suitable for ground floor heating in
a house), then we can only return to two systems which we think are ‘best’...and
that depends on your flooring...
If you want a timber floor, such as laminated wooden flooring or engineered timber,
then UFH is probably the best way to go. It will provide you with real comfort, and
is very controllable and quick to warm. You can have a ‘wet’ system of plastic piping
loops embedded in the floor with the water in the pipes heated by a gas boiler, a
heat pump(!), or even an electric flow boiler. Or you can simply use a ‘dry’ system
- electric heating mats (although there are serious issues with carpets holding the
heat back!). The wet system is far more complicated, and relies on a manifold of
tubes going out (and back) to all the rooms. The control (by the air thermostat)
is at the manifold - as it allows warm water to flow to a room or not. And as we
said before, you do have to remember that the output for wet UFH isn’t great.
Obviously a wet system also relies on a heat source, as we said - boiler or heat
pump. ‘Greens’ like this as it lends itself towards heat pumps very well due to the
low flow temperatures...it’s just the silliness which comes as a package along with
the heat pump which we can’t bide. Heat pumps are not the answer to Britain’s heating
requirements for so many reasons that we can’t go into here. You would do better
(if for any reason you don’t want a gas boiler) to use an electric flow boiler...if
you want a wet system. But why, when you could use a dry one? The boiler is an unnecessary
purchase to achieve the same end - electric heating.
If you still like your carpets (and many Brits do) then in-floor heating is the way
to go. Taking up just a small section of flooring, it is pretty much perfect - and
can eliminate condensation all on its own when fitted alongside a large glass window,
for example. Retrofit isn’t great for it, as your flooring would have to be dug out
(unless you’re lucky enough to have a timber suspended floor). But installing during
a new build or complete refurbishment is quick and relatively cheap.
In-floor heating is low maintenance and so low (or no) ongoing cost. You want it
truly whisper quiet, or it may wake you before your alarm clock does! The fan-assisted
heaters are shorter in length than the natural-draught ones. It suits all types of
homes, though it should be remembered that this type of heating was used in churches
over 100 years ago - and used quaint cast iron grilles, so it can easily look good
within a traditional home. Arguably the perfect heating system at typically less
than £5,000 (purchase cost) for an average home.
A heat pump extracts heat from the air (or ground if a ground-source one) and moves
the heat into the home. The downsides are numerous. They use electric in addition
to the heat gained from the air, they don’t work at all well when it’s cold outside,
they have to run continuously, they are expensive to install, they must be annually
serviced, and the flow temperatures are way lower than a boiler, at around 55° C,
so will struggle to heat your water cylinder. That temperature of 55° C is also a
bit misleading, as heat pumps are at their most efficient when run at 40° C! At that
temperature, it would struggle to heat your home on cold days unless you happen to
live in a passive house (VERY highly insulated) and would never heat your hot water
cylinder! High temperature (HT) heat pumps can operate at 80° C and so could potentially
heat your current radiators...but...HT heat pumps are more expensive to install and
are less efficient than low temperature heat pumps. The bit that sits outside is
also larger. The truth is that if your heat pump can’t cope, the electric element
will kick in, so you end up with an electric heating system. Heat pumps also fail,
of course, so will cost you in maintenance. The whole idea of heat pumps as some
sort of saviour of heating in Britain is so typical of the way this country is run
- badly. So we’ll put this as simply as we can... When you take account of all the
costs - purchase, maintenance, increased electric bill of a heat pump - you will
NEVER pay less for your heating system than you’re currently paying. So what if you
don’t have a heating system, and you’re starting from scratch? It’s still cheaper
to install (and run) an electric heating system than a heat pump one! That stark
fact should end any interest in a heat pump (unless you are one of those who think
you are saving the planet - in which case, go ahead for your ease of mind). In essence,
they don’t ‘work’ and are not a replacement for a gas or electric boiler, due mainly
The insanity of Net Zero by 2050 will require electric heating in some form or other
to be adopted by everyone eventually (unless our government sees that insanity before
2050). So it’s just what form of electric heating. Heat pumps are electric as they
put electric energy in to get heat out (of the ground or the air). So an ideal might
be solar panels (very efficient ones yet to be invented!) providing the electric
for you to use to heat your home, so that you aren’t even connected to the national
grid. As we said, that’s an ideal. In reality, you will almost certainly still draw
power provided by a cable coming from your street.
If some experts are correct, the warming of our homes is about to become of major
significance...and not in the way that you think. There are climatologists who believe
that we are about to enter a Mini Ice Age (much like when the Thames froze over between
1600 and 1800) due to solar activity and Earth’s orbit around the Sun, in about 15
years from now. If that’s so, then how we heat may be incredibly important - since
we may not have the energy capacity to cope with the demand. We may see a return
to wood burning at least, if not coal! Time will tell.
Although ‘conditions’ of heating is perhaps a primary factor (such as reliability
and comfort), cost is always there. Heat pumps are costly, but much more importantly,
have serious ongoing costs. So let’s look at the raw costs of opposing systems for
a system requirement of 10 x rooms of 14 square metres each, with a total load requirement
of 15 kWh. We’re going to assume UFH for the heat pump system, and we’re going to
assume it’s a new-build home or renovation project.
Full 10 x room in-floor heating system, requirement of 15 kWh.
Cost of trench heaters...£4,500
Cost of 10 x air thermostats...£500
Cost of labour for total install...£4,560 (based on our own cost of a typical install)*
Full 10 x room heat pump installation of UFH, requirement of 15 kWh.
Cost of UFH materials...£14,000 (based on nu-heat renovation costs)
Cost of labour (for whole system, including heat pump)...£11,680*
Cost of heat pump...£3,000 (British Gas - after £5,000 government discount)
So, it would look like a heat pump system is TRIPLE the cost of an in-floor heating
system! BUT...you may say that the running costs of the heat pump system will be
a LOT less than the electric trench heating system. That’s true...BUT, the ongoing
cost of the trench system will be zero, with no maintenance or servicing issues.
Whereas the ongoing cost of the heat pump system (maintenance and servicing) will
be considerable. So not only would you be £19,120 better off on install costs of
the in-floor system, you’d have virtually nothing further to pay.* It’s also possible
to consider a full UFH system heated by a gas boiler. In this case, the likely install
cost would be around £12,000 with fairly low running costs, though there would be
ongoing maintenance and servicing costs with a gas boiler.
*Trench heating system install costs include electrical work and assume new build
or total renovation project. Trench heaters do require some annual cleaning with
a vacuum cleaner, and elements may fail in the future, but are easily replaceable.
Cost of UFH system labour assumes new build or renovation, so is a minimum. If you
didn’t use British Gas, your heat pump would be much more costly, but your labour
costs would be likely lower.
Written by Barry Foster
The opinions expressed here are not just biased toward electric trench heating because
we market and install it! It is based on 48 years of heating & hot water installations
- our experience and research. You should carry out your own research on what’s best
for you, and your home. But we are here to help...firstname.lastname@example.org
As the insane ‘Net Zero’ draws closer, and gas boilers get banned, what is an alternative?
First of all, let’s rule out heat pumps. Heat pumps are hugely costly to install,
they have to be allied to a heating ‘system’, and they don’t very well lend themselves
to heating hot water. So what’s a good alternative? It’s something called ‘in-floor’
heating...and it’s electric.