Help with heating & hot-water options

itramsitra

Hello,

I'm about to buy a 4 bed house (roughly 100 sq m) that has a gas boiler with a hot water tank & a cold water tank. This is quite dated & needs updating. I'm so confused with all the various options & would really appreciate some advice.

I love underfloor heating but don't want to do the wet UFH installation (It's expensive and also needs a gas boiler - which is going to be outlawed in a few years, from what I understand).

The electric UFH is cheaper to install but more expensive to run. But I've been told about a ribbon electric UFH which supposedly can be used as a primary source because it has more coverage and is therefore cheaper to run than the regular electric UFH.
(I can't post a link here, but if you google 'ekobuild underfloor heating mat' you should see what I'm talking about.)

There's the option of getting a heat pump (Octopus has quoted me £5000 for this.)

There's the option of getting solar panels (quote of £13500) but I think I'd still need some other heat source as a back up to the solar panels.

I am just overwhelmed by the options and am stuck in analysis paralysis! Please help!\

Thank you

MattMattMattUK

itramsitra said:

Hello,

I'm about to buy a 4 bed house (roughly 100 sq m) that has a gas boiler with a hot water tank & a cold water tank. This is quite dated & needs updating. I'm so confused with all the various options & would really appreciate some advice.

I love underfloor heating but don't want to do the wet UFH installation (It's expensive and also needs a gas boiler - which is going to be outlawed in a few years, from what I understand).

Wet underfloor heating does not need a boiler, it can run from a heat pump and a heat pump is ideal for wet under floor heating. Gas boilers are also not going to be banned in a few years, new builds with gas boilers will not be allowed, but replacement of existing boilers will be allowed for a decade or more and there will likely be no phasing out of mains gas until at least the 2040s.

itramsitra said:

The electric UFH is cheaper to install but more expensive to run. But I've been told about a ribbon electric UFH which supposedly can be used as a primary source because it has more coverage and is therefore cheaper to run than the regular electric UFH.
(I can't post a link here, but if you google 'ekobuild underfloor heating mat' you should see what I'm talking about.)

Electric under floor heating is the most expensive way to heat your house. Ribbon or mat is the same cost per kWh of heating, 1kWh of electricity in, 1kWh of heat out.

itramsitra said:

There's the option of getting a heat pump (Octopus has quoted me £5000 for this.)

£5,000 would be on the cheap side for a heat pump, they also generally require radiators to be replaced with larger radiators, often changes to plumbing and hot water tanks etc. They have a higher upfront cost but are cheaper to run than pure electric, however more expensive than gas unless you have solar, and potentially battery storage.

itramsitra said:

There's the option of getting solar panels (quote of £13500) but I think I'd still need some other heat source as a back up to the solar panels.

Solar panels (PV) are not a heat source, they generate electricity. If you were going to spend as much money as you appear to be prepared to then you would be best getting a large solar array (paying the extra for 8kWp if you have the roof space) and getting a heat pump, battery probably would not give you a positive ROI for 15 years so may or may not be worth it.

diystarter7

Hi OP

No offfence but 100Sq mts house is not that big and only slightly bigger than the average 1960's semi or detached houses.

Underfloor heating is not essentail where as imo it is in larger houses.

However, IMO, you can't beat UFH especially if house is realtively open plan and just have it on the ground floor.

Think long term, what you feel you really want, sleep on it, seek several quotes for that type of heating and move forward.

UFH gives you a lot more freedom to place furniture etx and even havefloor to ceiling glass wall looking into the garden

Then check the feedback etc of the co you want to use and always pay at least enough via cc to give you extra consumer protection

I know your questions were slightly different but we have been there and even when I/we have planned and think we went for the best option, days or months down the road we could have done it differently

Thnaks

itramsitra

MattMattMattUK said:

Wet underfloor heating does not need a boiler, it can run from a heat pump and a heat pump is ideal for wet under floor heating. Gas boilers are also not going to be banned in a few years, new builds with gas boilers will not be allowed, but replacement of existing boilers will be allowed for a decade or more and there will likely be no phasing out of mains gas until at least the 2040s.
Electric under floor heating is the most expensive way to heat your house. Ribbon or mat is the same cost per kWh of heating, 1kWh of electricity in, 1kWh of heat out.

Oh I didn't realise you could run wet UFH with a heat pump! That's great to know. Thanks so much for your detailed answer. I think heat pump + wet UFH is probably what I'll end up choosing then. 

Thanks again!

matelodave

Dont even think about electric underfloor heating, it may be Ok for an hour or so in a bathroom but the running costs will cripple you if you use it for whole house heating, especially the overlay type. Embedded systems can use off-peak leccy as heat is stored in the concrete but overlay types need to run during peak times

Properly installed (in the concrete) or even an overlay wet underfloor heating systems are ideally suited to heatpump systems as they run at a lot lower flow temperature than radiators. However there are some caveats.

Underfloor systems are a lot slower to respond to temperature changes as they work more like storage heaters, especially those that are embedded. Overlay systems are a bit quicker., Coupled with a heatpump can make it even slower so they are suited to being run for much longer. 

We've got 140sq.m bungalow with an overlay underfloor system with a heatpump. It works well for us because we are at home all day and we dont let the place cool down too much overnight. Even dropping the temp by 3-4 degrees can take a couple of hours to recover on a very cold morning.  (It can take 24-36 hours to get the place back up tiotemp if we let it get stone cold. In fact when we go away on holiday in the winter we time the heating to come on 24 hours before we get home

Make sure when you do the heat calcs for u/f heating you take into account what sort of floor covering you are going to use. Tiles are best and carpet is probably the worst but acceptable if you specify low tog carpet and low tog underlay.

You also need to take into account what sort of furniture you've got. A nice warm floor doesn't help heat the room when there's a ginormous three piece suite, sideboard and other stuff covering it. Likewise in the bedroom, a chest of drawers, wardrobe and double divan than goes down to the floor can cover a fair area so make sure you take it into account in your calculations (they are the things we missed when doing ours)

I'd also suggest that you try and insulate underneath the heated floor if you can - we have an overlay on a suspended wooden floor and we didn't . Although it works OK (and has done for 13 years) I'm sure it would have reduced the energy costs and improved the heating performance, but we couldn't quite go the whole hog and rip up all the flooring to accommodate u'f insulation, but its something I'd do if I was doing it over again.