Under Floor Heating

mattghi007

Hello,

I'm new to the forum and wanted some advice from some expert money savers please!

I have recently moved into a cottage with UFH in a recently built (2004) kitchen and utility room extension. There is no other source of heat in these rooms and each has a devireg 550 thermostat fitted (replaced recently as they were duff!) The total floor area is around 25 sq metres and is tiled.

I've had the system setup to come on for 5pm and go off at 9pm and its set to 5 (equating to 20 degrees). It seems to be taking 12 Kwh of electricity per day to run which @ 24p each is equating to £2.88 per day that's £90 per month, just for the floor!:eek:

Is this correct? everyone i talk to says electric ufh is cheap to run some articles say as low as £100-£200 per annum not a month!!

I'm on eco 7 would it be more cost effective to run the floor overnight to do its initial heat up on the cheaper electric and then just maintain a temp during the day? I've tried reducing hours on and the temperature but the difference in usage is very minor, pointing to the initial floor heat up being the culprit of most usage.

Any tips on how best to run it would be gratefully recieved!

Oh yeah, and I've just found out that British gas have had my meter readings the wrong way round so i'm bracing myself for a massive bill! Oh the joys!

Cheers

Matt

Procrastinator333

Electric underfloor isn't suitable as a primary heat source due to the cost. It is very expensive! Really it should be used as a secondary, something so feet don't get cold when walking round the bathroom.

Do you have central heating? I would see about adding some rads and extending the ch runs...

Andy_WSM

mattghi007 wrote: »

It seems to be taking 12 Kwh of electricity per day to run which @ 24p each is equating to £2.88 per day that's £90 per month, just for the floor!:eek:

Is this correct?

No, it is not correct as you don't pay 24p per unit for electricity.

You may well pay this for Tier 1 units (these include the standing charge), but you will use these regardless in any billing period, so for consumption purposes you should be using Tier 2 prices, which will likely be half or less than that of Tier 1.

jackyann

Underfloor heating is designed to run at a fairly low level, and works best in a well insulated house. I agree that electric underfloor heating is very expensive - is there any possibility of converting it to gas? I realise that even if there is, the cost may not be worth it.
I would certainly try running it for longer - have you worked out at what point the thermostat cuts the heating off? If it is taking a few hours to get to the desired temperature, you may need to re-consider your timing.
I would also check your insulation (sorry if that's obvious) but ufh does not work well if required to heat a cold room quickly.
Obviously I don't know your set-up, but I think of a utility room as a pantry or scullery, to be kept cold (we don't heat ours) so I wonder if you could save by switching it off or to very low there.

mattghi007

Andy_WSM wrote: »

No, it is not correct as you don't pay 24p per unit for electricity.

You may well pay this for Tier 1 units (these include the standing charge), but you will use these regardless in any billing period, so for consumption purposes you should be using Tier 2 prices, which will likely be half or less than that of Tier 1.

Thanks for the response Andy, but British Gas confirmed to me that standard rate electricity is indeed 24p per kwh, the tiers you refer to are 26.9pence tier 1, 13p tier two and 5.6p night from what I've been told. As the floor is not on at night the best I can hope for is the 13p rate I guess and even so that'd still work out at £50 per month just for the floor on our consumption

mattghi007

Thanks to all for replying to me the newbie!

At bit more info...

We have no other source of heat in these rooms, and from what I've read I tend to agree that the general opinion is that it shouldn't be used as the main source of heat! Sadly for us it may have to be - esp in the winter as running radiators may be prohibitively expensive for now. I haven't checked the insulation but pulling the floor up isn't really on the cards. As I say the extension is quite recent and the walls are cavity insulated etc etc.

My real question is how to run the system most efficiently - I have reduced the heat to 'just take the chill off to tiles' but as i say the consumption never really drops...and yet all the UFH heating sites you go to tell you is cheap to install and economical to run LOL

WestonDave

Firstly assuming you are using some electricity for lighting, TV, kettle etc, its likely that even without the Ufh on, you are using all your tier one rate units - so the relevant rate for deciding how much your Ufh is costing is the tier 2 rate (its what economists call the marginal rate - the cost of adding one more unit over and above the baseline cost).

Secondly although science and logic says only have the heating on when you are using it - hence presumably the 5pm to 9pm usage when you are home from work, there might be some scope for making use of the 5.6p night rate to get the heat into the tiles or at least keep them from cooling overnight so that when you come to use the room in the evening its warmer.

25 sqm is a big old area to be trying to heat - is there any way of closing off the utility room part of it for example.

The other question is whether you'd be better off getting a couple of 1Kw panel heaters or oil radiators- one at each end of the room, and using them. For the same time period you could only possibly use 16Kwh of electricity and possibly less if the thermostats on them cut out. Whether supplementing that by having the Ufh on for an hour right at the end of the night rate would help is probably a matter of trial and error to see how much heat is lost during the daytime.

HappyMJ

UFH is only cheap if you have a heat pump. Anyway it is £200 per annum as you have seen advertised. You need the heating for 5 months of the year. That will be £40 per month. Then you need to select a good tariff such as 10p/kWh for all units. That will give you 400kWh per month or about 12kWh per day which is what you do use.

Do you have gas central heating? If so then consider a switch to a standard electricity tariff if your night usage is under 30% of the total kWh on the bill.

Richie-from-the-Boro

What is eco 7 ? - Does it mean Economy 7 tariff ?

If anyone is using any electricity anywhere between 7am & midnight [ish] on E7 tariff you are paying full price ++ per kW appliance / use. The only economic benefit to be had from UFH on an E7 tariff is midnight & 7am [ish].

Putting UFH on outside these hours is an expensive option - you decide.
Installing a night-store heater [cheap tariff only] or panel heaters [expensive tariff] in addition to UFH in your kitchen is a better option.

jackyann

UFH can be economical without a ground (or air) source heat pump - which are not necessarily that good value.
Gas ufh is OK, and so is using ufh as a main heat source - in houses which are well insulated, using ufh throughout and also especially if it is needed for most of the day.
It really is horses for courses, and sometimes when you buy a house you don't quite realise these little quirks.

chris1973

Underfloor heating isn't a type of heating which takes advantage of the E7 tariff, unless you can stay up all night and sleep all day. Sadly, floors will not 'store' heat for later in the day so if you run the UFH during the E7 period it will be nice and warm........when you are in bed asleep. By the time you get up, the floor will be cold and any residual heat in the rooms gone.

If you have an E7 tariff, then you would be much better fitting storage heaters as already mentioned, this way you will be able to store the e7 period heat, and at least get the benefit from it during waking hours.

If you intend to use the UFH or 'real time' heating such as Electric Fires and Convectors, then you would be better off, shopping around for a better standard tariff, as E7 users tend to pay a premium for daytime electricity, in return for their cheaper overnight rate - since you are using the bulk of your electricity for heating outside of the E7, period then you are much worse off on E7, than moving back to a standard tariff.

So, in the absence of Gas or Oil CH, or a Ground / Air source heat pump you have the following options:-

1) Keep the E7 tariff, and get storage heaters to run from it, and benefit from the cheaper overnight Electricity

2) Keep the underfloor heating, and / or convector heaters / fan heaters / halogen heaters, but scrap the E7 and get a more competitive tariff with a single rate which is lower than your current E7 daytime rate.

Unfortunately, no electric heating is cheap, largely because electricity in the UK is a second tier energy, and reliant on another form of energy first being produced and purchased in order to produce it. For example Gas has to be purchased at a profit, in order to burn and produce steam which then turns the turbines which produce the electricity, which then also has to be sold on at profit.....then the distribution and middleman inbetween have to be paid, not to mention two lots of shareholders.....