Electric Underfloor Heating Running Costs

chazwil

Hi, I'm new here and was wondering if someone might be able to provide me some advice. I'm in the process of looking to buy a house and I have found something that I like. The only issue is that it's electric only, there's no gas supply. It has been recently converted and has electric underfloor heating as the main heating source throughout its 60mtrs sq. Does anyone have any ideas about running costs? I work full time, currently the place where I live is heated by gas so my heating hours are a couple of hours in the morning and from about 17:30 until 23:00 and all day at the weekend.
Any help, tips would be appreciated.

Aylesbury_Duck

Electricity is about 3-4 times more expensive per unit (kWh) than gas, but electric heaters are 100% efficient whereas gas boilers are not, the most modern being around 90% efficient. That still makes electricity more expensive than gas so for a rough calculation, take whatever it costs to heat your current approximate floorspace and it will cost roughly three times that much to heat the same space with electricity. Scale that up or down according to whether your new place is bigger or smaller than your current place.

All of this is very approximate because we don't know the levels of insulation, whether one is ground floor and the other is higher, whether the house is south-facing or shielded from the sun and so on. The reality is that you won't know until you move in and begin seeing bills come through.

The only tip I have with underfloor heating is to learn how it behaves so that you learn how far in advance of needing heating to turn it on and to understand that it gives off a lot of latent heat, so if you wanted the place heating between say 6am and 8am then you will probably time the heating to come on a 5am and go off at 7am.

J_B

Can you run electric underfloor on Economy7?

chazwil

As far as I know it's running on standard rate.

chazwil

Aylesbury_Duck wrote: »

Electricity is about 3-4 times more expensive per unit (kWh) than gas, but electric heaters are 100% efficient whereas gas boilers are not, the most modern being around 90% efficient. That still makes electricity more expensive than gas so for a rough calculation, take whatever it costs to heat your current approximate floorspace and it will cost roughly three times that much to heat the same space with electricity. Scale that up or down according to whether your new place is bigger or smaller than your current place.

All of this is very approximate because we don't know the levels of insulation, whether one is ground floor and the other is higher, whether the house is south-facing or shielded from the sun and so on. The reality is that you won't know until you move in and begin seeing bills come through.

The only tip I have with underfloor heating is to learn how it behaves so that you learn how far in advance of needing heating to turn it on and to understand that it gives off a lot of latent heat, so if you wanted the place heating between say 6am and 8am then you will probably time the heating to come on a 5am and go off at 7am.

Thanks for your helpful response Aylesbury Duck, it's very difficult to give more information at this early stage, I'm waiting to get a copy of the EPC and see what that says. I'm guessing that the conversion will be to current building regs.

Slinky

From what I saw of the EPC for the house we bought last year, they're pretty useless. There's lots of 'assumed' based on the age of the house, and precious little looking. The surveyor who did ours couldn't even be bothered to look in the loft to see how much insulation there was and assumed the cavity walls weren't insulated which they turned out to be. The building surveyor could tell somehow that the cavities had been filled without drilling into them to check, so it's obviously not rocket science.

Furts

chazwil wrote: »

Thanks for your helpful response Aylesbury Duck, it's very difficult to give more information at this early stage, I'm waiting to get a copy of the EPC and see what that says. I'm guessing that the conversion will be to current building regs.

You cannot guess anything, and even if it is a recent conversion nobody will know what standard the work has been done to. Conversions are notorious in this respect - it will always be a case of may do and mend, because that is the nature of things. With new build one starts with a blank canvass and can move straight to good practice from there. With conversions you work with what you have.

Even if the floor has insulation to try and prevent heat loss downwards if the converted shell is riddled with holes and drafts - which you will not immediately see - then your heating bills will be high.

All round it is a complete unknown - but with any conversion always be very wary. So factor in something to be on the safe side.

chazwil

Slinky wrote: »

From what I saw of the EPC for the house we bought last year, they're pretty useless. There's lots of 'assumed' based on the age of the house, and precious little looking. The surveyor who did ours couldn't even be bothered to look in the loft to see how much insulation there was and assumed the cavity walls weren't insulated which they turned out to be. The building surveyor could tell somehow that the cavities had been filled without drilling into them to check, so it's obviously not rocket science.

The EPC will help me decide but I would get a surveyor in to give the place a once over. But I totally understand where you're coming from on that.