Should I get underfloor heating?

victor2

Wet UFH has water running through it, just like conventional radiators.

People I've met with UFH praise it for the lack of obtrusive radiators, but do say it has to be on pretty much 24/7 to keep the temperature up, as it is very slow warming up a cold house.

anon_ymous

victor2 said:

Wet UFH has water running through it, just like conventional radiators.

People I've met with UFH praise it for the lack of obtrusive radiators, but do say it has to be on pretty much 24/7 to keep the temperature up, as it is very slow warming up a cold house.

I guess even if it was powered by gas, it'd still be quite expensive to run? Is wet UFH better than dry UFH? 

ArbitraryRandom

waqasahmed said:

fenwick458 said:

getting it to save money, I wouldn't bother, it's expensive to install.
if you like hard floors, they are often cold (compared to carpets) thats why I chose UFH.
the heat source is more important if you are wondering about saving money, if you put a wet UFH system onto a combi boiler that also does radiators, it's not going to be efficient as you need to run 2 sets of times.

Sorry what's wet UFH? 

There are two different types of underfloor heating: Electric and wet. 

Wet means running pipes under the floor connected to your boiler, like an underfloor radiator. Electric is running wires under the floor, like an electric blanket on a bed. 


This link gives some pros and cons of each option https://www.warmup.co.uk/blog/electric-underfloor-heating-vs-water-underfloor-heating

One thing that's not mentioned in that link (and might just be my limited experience and might depend on your covering flooring choice) is that electric underfloor heating is easier to repair if there's a problem. If it's installed room by room then the heating issue is only in that room and there's not the risk of water leaking under the floor. 

Bendy_House

waqasahmed said:

Thanks. I'm already looking at further insulation but I'm not sure of any reputable companies within the greater Manchester area for that. The house is already pretty well insulted but it'd be nice to have more where there currently isn't.

I'm also looking into getting solar panels too, but I guess insulation is the biggy

I'm guessing that gas powered UFH doesn't exist 

Most UFH are 'gas' powered, via a conventional gas boiler. However, it isn't worth retrospectively fitting UFH to save energy costs as the installation cost is so high. It would only be worth doing if it's part of a new build, or a major renovation where the floors would already be ripped up.

If you hope to install PV panels, and use these to help heat your home, then you will also need a 'heatstore', which is a large hot water storage tank. This can be heated up by many energy sources, and the stored hot water then used to provide heating for the house. PV panels would heat it up via an immersion heater, and this could be used to supplement the main energy source which would still likely be a gas boiler, or perhaps an ASHP.

anon_ymous

Bendy_House said:

waqasahmed said:

Thanks. I'm already looking at further insulation but I'm not sure of any reputable companies within the greater Manchester area for that. The house is already pretty well insulted but it'd be nice to have more where there currently isn't.

I'm also looking into getting solar panels too, but I guess insulation is the biggy

I'm guessing that gas powered UFH doesn't exist 

Most UFH are 'gas' powered, via a conventional gas boiler. However, it isn't worth retrospectively fitting UFH to save energy costs as the installation cost is so high. It would only be worth doing if it's part of a new build, or a major renovation where the floors would already be ripped up.

If you hope to install PV panels, and use these to help heat your home, then you will also need a 'heatstore', which is a large hot water storage tank. This can be heated up by many energy sources, and the stored hot water then used to provide heating for the house. PV panels would heat it up via an immersion heater, and this could be used to supplement the main energy source which would still likely be a gas boiler, or perhaps an ASHP.

Would it be worth putting in UHF if say I'm putting in insulation for solid floors? And in that regard, I'm guessing wet is better than dry? 

BikingBud

Rosa_Damascena said:

Wet UFH has definitely saved me money - it's been too expensive to run so my heating has been switched off since January!

@Rosa_Damascena And how much would normal GCH be in comparison? 

Rosa_Damascena

BikingBud said:

Rosa_Damascena said:

Wet UFH has definitely saved me money - it's been too expensive to run so my heating has been switched off since January!

@Rosa_Damascena And how much would normal GCH be in comparison? 

I have no idea. There were 3 variables compared with 2021:

• new UFH
• a lot more space to heat
• a massive jump in the cost of energy, even at the rate I fixed it at in October 21.

Either way the GCH would be switched off.

Bendy_House

waqasahmed said:

Would it be worth putting in UHF if say I'm putting in insulation for solid floors? And in that regard, I'm guessing wet is better than dry? 

'Worth' it? Probably not from an energy-saving pov, as the installation cost will be a lot more than just fitting larger rads. So you'd only fit UFH for two main reasons; the comfort it offers (just superb) and the convenience of not having wall-mounted rads.

So, I'd suggest THAT should inform your decision whether to go UFH, since - energy-wise - oversized rads should perform the same job in a well insulated home.

As to wet vs dry, I'm assuming 'dry' means 'electric', and that - obviously - needs electricity. Two ways to get this - from the mains (the most costly form of energy), or via batteries (which will require either whopping PVs and/or charging on a cheap rate.) I don't have sums for these, but my gut says the former will bankrupt you, and the latter just send you over the poverty threshold.

I 'think' that the number of batteries required, coupled with a large enough PV for max benefit, would be a massively costly install. But could then be a cheap runner. Until the batteries fail.

So, dry would NEED electricity = generally avoid.

'Wet' can be supplied by ALL energy sources, including electricity. So it seems to me to be the obvious way to go.

A house we looked at a few years ago was out in the sticks, so oil and LPG were the only sensible choices. The person who renovated the place decided instead to go 'electric', and they had a large PV array (can't recall, but I'm guessing 4-5kW?), a battery (yup, only one...), UFH, but powered by an electric combi, so still a 'wet' system, and not dry. They were signed up to 'Smart' electricity (supplier) and had an arrangement that 'Smart' could pinch surplus leccy at peak times, and they'd get cheap leccy at other times. I couldn't get an actual running cost figure from them (the renovation had only recently been completed, so no even medium-term tests), but my best guesstimate was that it could be similar to oil, and that would have been good enough for me. Of course, oil has since gone up more than leccy, so hopefully it's now better still.

Being 'wet', the option remains to change to, or add, other heat sources such as ASHP or biomass or even a back boiler in a stove. 'Dry' wouldn't allow that.

ASHP are going to tumble in price, almost certainly (Octopus is on the case...), and almost certainly their effectiveness/efficiency will also be increased (eg talk of CO2 as the refrigerant).

Bendy_House

Get quotes for both systems, Waq; wet UFH and oversized rads, and make your decision?

I personally wouldn't go dry UFH at all at all. It's really only good for adding the 'luxury' of UFH to small areas such as bathrooms, where the installation of a small area of dry UFH would be MUCH simpler and cheaper than adding 'wet' to a small room.

Wet UFH has complex controls, so would only be bothered with for a main living space or a whole floor, and never fitted to just a small room on its own.

Anyhoo, get quotes and decide!

Would I go UFH if I was renovating a house and was laying a solid floor in any case? Yup, absolutely, for both it's comfort and its potential to be efficient (IE low water temp). But, I'd be doing the install myself so would save £ks...

Please remember two things, tho'; one INSULATE EXT WALLS (on their insides, ideally) and floors, and two, fit OVERSIZED rads, choosing locations that simply fit in and look best. On our new extension, I fitted a tall column rad to each beam support pillar, and I actually like the look; rads don't have to be an eyesore.

ComicGeek

UFH works well when you have a well insulated building with high thermal mass as it can provide a very even heat - ie, concrete floors/walls, exposed concrete/dense block walls etc. It doesn't work as well when it's poorly insulated, or very lightweight construction (ie timber framed, plasterboard lined etc) as those respond much quicker to outside temperature changes than the UFH can.

UFH doesn't work well when there are large areas of glass - not only is the heat output required higher (which the UFH may not be able to deliver in the depths of winter), but the amount of solar heat gain can be huge. We were on holiday in April in a house with large south facing bifolding doors and rooflights and UFH - whenever the sun came out we just baked, and the UFH was still pumping out heat for about an hour. Then the sun went behind clouds, and the UFH took another 2 hours to heat up. A radiator based system would have responded much quicker in both cases. 

I much prefer the non screed systems (so where a profilled insulated panel is installed on top of an existing floor), as they respond much quicker and don't have to heat up the mass of screed first. But that's more expensive for new floors where it's cheaper to just chuck in some cheap pipe and pour the screed.

Personally I would never get UFH myself unless I had a very well insulated and air tight house with exposed thermal mass internally and very good external shading on any glazing areas. You will struggle to find many of those in the UK.