Electric Underfloor heating advice needed

StephLSJ

Hello,

We're looking at getting electric underfloor heating in our living room and hall. I'm struggling to find any unbiased information about running costs. We live in an a fairly standard 1930's three bedroom semi-detached house.

Has anyone had electric underfloor heating recently installed? How did affect your electricity bills?

Thank you

Steph

Gerry1

Don't even think about it !

Would you buy a car that needed special petrol that cost £6 per litre? :eek:

You'll need full price electricity which is about 5 times the cost of gas.

https://nottenergy.com/resources/energy-cost-comparison/

https://www.energysavingtrust.org.uk/about-us/our-calculations

JohnB47

StephLSJ wrote: »

Hello,

We're looking at getting electric underfloor heating in our living room and hall. I'm struggling to find any unbiased information about running costs. We live in an a fairly standard 1930's three bedroom semi-detached house.

Has anyone had electric underfloor heating recently installed? How did affect your electricity bills?

Thank you

Steph

We have a similar house and have electric UFH installed in our bathroom (around 5 or 6 square metres).

The costs depend on usage. We have ours on for around an hour each morning, turning on 50 mins before we intend to go in and going off 10 mins after. Set to heat to 27.5 degrees. We have large porcelain tiles there and they hold the heat for a while. We don't use the UFH at night - just the mornings.

I've never really noticed the difference in our electricity bills - the extra cost of UFH is probably being masked by the cost of the Tumble Dryer we use.

Some advice:

Make sure your installer has done this sort of thing before.

He/she needs to plan good coverage and to ensure anything put above is applied correctly. Our nitwit installer didn't use a solid block of adhesive under each tile, he used dabs of it instead, so we have cool spots. Oh and the tiles move a bit, so parts of the grouting cracks over time and needs redone. Idiot.

Secondly, make sure the sensor is placed inside a tube, under the tiles and that the tube and sensor is accessible outside of the underfloor - so that you can retract and replace the sensor if you need to. Our nitwit brought the tube and sensor lead out from under the floor then trapped it at the bottom of a stud wall. Lots of digging to get at it when the sensor was discovered to be faulty.

Lastly, think about the programmer that comes with the UFH. Ours is too simple. If you set on/off times for one week day, those settings apply to all week days. You can set different on/off times for the weekend but again, it's the same for both days. I would have wanted a more flexible timer - one that allowed different on/off times for each day.

Edit: also, we use ours only in the cold part of the year - October to May and our bathroom also has a large heated towel rail (dual electric/Central Heated), so the UFH is really just to give a cosy feel, not to fully heat the bathroom on it's own.

Personally, I would not use this type of UFH for the areas you suggest.

matelodave

It will probably be expensive.

Most electric u/f systems work out at around 150watts/m2 so work out the size of your living room and hall in m2 and that will give you a rough idea of the power consumption. (living room 4m x5m=20m2 x150w= 3kw). Ideally you need to do a heat loss calculation to see if 3kw is enough to keep you warm enough when it's cold otherwise you may need supplementary heating as well.
Last but not least work out how much of it will be covered by furniture which will reduce the amount of heat that can be dissipated into the room rather than heating the bottom of the settee or sideboard.

At 3kw it will cost around 45p an hour to run whilst it's heating the room but it should drop when the thermostat cuts in however it's not going to be cheap. The hall may never get up to temperature if it's a bit draughty so it could be flogging away for hours.

What sort of floor have you got, a lot of 1930s houses had suspended floors so you really need to insulate under them otherwise you'll be keeping the wildlife underneath warm as well.

You also need to take into account what sort of floor covering you are going to use - ceramic tiles are ideal but be careful with laminate or engineered wood to ensure that it will cope with a warm/hot floor. Low tog carpet and underlay is a must if you are going to lay carpet over u/f heating.

IMO they are OK for a bathroom where the area to be heated is quite small and they are only on for an hour or so a day. I'd be very reluctant to make it my main form of heating in the lounge or hall where it will be used for a much longer period of time