Big house, considering moving away from gas to electric only

[Tweetie]

I have a big house (250m2) which is in need of total renovation and I am planning the new design.

Currently there is an old gas central heating system with loft tank, immersion tank and several pumps needed to push the water around etc. 16 radiators. The house is well insulated.

Despite the large house, there are only 2 of us and it is occupied all day. I do not intend to plan for extra people.

I would really appreciate your opinions on what I am considering, which is

To do away with gas entirely
Have electric under-floor heating installed throughout
With the downstairs floor area fully tiled and the upstairs area fully oak floored
Install an electric power shower which heats its own water
Then some sort of either immersion tank for the bath and kitchen & utility sinks, w/c sinks etc or an instantaneous electric hot water system if it exists.

Finally, I have a large south facing roof (un-shaded) so a good contender for solar electricity – although I understand that the costs of installation can never really be recovered in savings.

 

[mickyg]

electric underfloor heating, immersion heaters, electric showers and any other form of electric heating is likely to cost you around 4-5 times that of heating the same things using gas so its a poor idea. Gas is your economical friend. Solar electricity is a green statement not an economical investment.
Fit wet underfloor heating, then if you wanted to you could feed this from a heat store connected to solar panels and a small gas boiler.

 

[electronicsuk]

As above, don't do it, you will almost certainly forever regret it. If efficiency and running costs are important to you but initial costs not so much so, upgrade to a more modern condensing boiler and better controls.

Suggest you look at Heatmiser's product range, as their system will allow you timed control over individual rooms as well as the capability for a central control point if you use their networked thermostats. I fitted this in a previous house and it is an excellent system.

If you really must go with electric heating, then you would do well to look at air or ground source heat pumps, as the running costs will be more comparable with gas. However, initial costs are far, far higher, and due to the low water temperatures in comparison to gas heating, these systems are only really suited to underfloor heating or very oversized rads.

Another important point to note if you plan on using UFH as your main heat source is the time taken for the floor and subsequently the building fabric to warm up. It really needs to be left on for long, continuous periods of time to work effectively.

 

[Tweetie]

If I keep gas, I will need a new boiler and all new radiators and controls. The existing system has really had it.

You suggest a wet underfloor heating - which I suppose will be for the tiled floor - but surely it has more risks of leaking, blocking, bubbling in the pipes or cracking the floor joints etc? Also, once tiles are down it would be near impossible to service.

I read that underfloor heating gives a more pleasant heat, but I really can't find out how much the running costs are.

 

[bengasman]

Running costs for ufh are not much different from normal heating if you are in all day; this goes for gas as well as electric heating including the quadruple cost of electric compared to gas.
I would not be surprised if the fuel bill for electric heating would come to £3000 per year for a house that size.

 

[Deleted member 105431]

gas is cheapest but ground/air source heat pumps are the cheapest to run electric heating but capital outlay is very high by comparison.

a c.h.p unit may be worth looking at too or a woodburning stove with a thermal store (sludge bucket).

 

[electronicsuk]

If I keep gas, I will need a new boiler and all new radiators and controls. The existing system has really had it.

It will soon pay for itself vs running costs for electric underfloor heating.

You suggest a wet underfloor heating - which I suppose will be for the tiled floor - but surely it has more risks of leaking, blocking, bubbling in the pipes or cracking the floor joints etc? Also, once tiles are down it would be near impossible to service.

There will certainly be more risk of leaks occurring on wet UFH than electric heating lol but the risk is minimal if correctly installed. The same goes for pipe blockages, cracks, etc. It would be just as impossible to service an electric system once the tiles are down. If anything, you will very likely find a wet system to be more reliable. Over time, electric heating elements break down, especially if laid directly in the adhesive rather than in a screed which can cause hot spots in the heating wire if the adhesive is not properly applied.

 

[mickyg]

If I keep gas, I will need a new boiler and all new radiators and controls. The existing system has really had it.

You suggest a wet underfloor heating - which I suppose will be for the tiled floor - but surely it has more risks of leaking, blocking, bubbling in the pipes or cracking the floor joints etc? Also, once tiles are down it would be near impossible to service.

I read that underfloor heating gives a more pleasant heat, but I really can't find out how much the running costs are.

Get your last gas bill that you had in a winter where you used the heating and hot water from the old boiler. times that by 5 and your about the cost of your next electric bill if you go that route. In any case installing loads of electric ufh has to be expensive anyway. If your after the cheapest most economical solution for short AND long term then a combi with rads will be your best bet most likely.

 

[Tweetie]

I currently pay about £2k a year for gas and electric but the system is inefficient.

I can budget for any type of system but it needs to be planned for and budgeted before the floors come up and the tiles laid.

So far, I really get the hint from you all that gas is cheaper although the websites that are selling the electric UFH say it is equally as economical.

What would be the absolute best system set up with gas? Would it be a normal condensing boiler with a big pressurised hot water cylinder, no loft tank, all mains pressure, power showers that use the tank's hot water, wall radiators upstairs and underfloor water pipes downstairs to warm the tiled floor?

I may as well find out how much the 'Rolls Royce' solution will cost - and work backwards if I have to. I will live here for years to come so want to get it perfect in one go.

 

[bengasman]

...What would be the absolute best system set up with gas?

That depends entirely on your wants and needs.

Would it be a normal condensing boiler with a big pressurised hot water cylinder, no loft tank, all mains pressure, power showers that use the tank's hot water...

With an unvented cylinder, you use normal mixers/showers as you have no need for pumps.

 

[Tweetie]

wants & needs…

warm house (250m2) all day (with controllable temps in each room)
no more than 2 baths or showers in one day (almost never even at the same time)
hot water to wash hands, wash up
sports car

 

[bengasman]

wants & needs…

warm house (250m2) all day (with controllable temps in each room)

Any boiler apart from the really small ones will do that.

no more than 2 baths or showers in one day (almost never even at the same time)
hot water to wash hands, wash up
sports car

In that case, a large combi will leave considerably more money to spend on the sports car, and do the job just as well.

 

[knuckles]

Buy a house with overheads that are more suitable for two people and let a family move in to a project.

 

[Agile]

You seem to believe all you read in a makers literature.

We are independent and give you impartial advice!

Gas is far cheaper.

You say your system is inefficient but dont say why. It will only be inefficient if the insulation is poor. thats what you shopuld be spending your money on.

There is a completely diffferent senario for a studio flat in a block and a large detached house.

In your case gas will always be cheaper.

I would question why you want to heat all the house if there are only two people!

UFH has to be on in virtually all the house all the waking house beause of the three hour warm up time!

I am not convinced you have understood all the facets if you still think electric UFH is cheaper.

Tony

 

[Tweetie]

No, I realise now that the makers literature is biased and that gas is cheaper - I wasn't doubting you just explaining why I first thought it was a good idea.

I would like individual controls so that I don't have to heat the whole house at the same time.

The house insulation is great but the boiler is very, very old (over 30 years) there's no thermostat and none of the trvs work, and even the programmer only works intermittently. The boiler no longer warms the hot water so the electric immersion heater has to be used.

Would a large combination boiler have enough oomph to pump hot water around a big house?

Is warm water underfloor heating compatible with a combination boiler?