Underfloor heating

typeractive

Hello all,

I have a few q’s about under floor heating. I’m in a position where I have ripped my house down to a shell (pretty much). I have lifted the kitchen floor as it was cracked due to being laid poorly in the first instance. I am thinking of installing under floor heating when I relay the floor.

A friend is doing a similar thing and has bought some electric kit from B&Q. Sort of like some pads that can be laid. Apparently it’s cheaper than he thought, hence why I’m considering it.

I don’t plan to keep the room warm just with the under floor heating – I will have radiators to cope with most of the heat, though I do want to use it to keep the chill off the tiled floor.

My concern is the cost of using under floor heating. I don’t want massive energy bills. So far I have only looked at the electric tiled kits. Though I was wondering if using the water piped system off the mains boiler would work out cheaper / more efficient to use?

Does anyone have any ideas? I would want the heat to be selectable, i.e. I can turn it on or off without having to switch off other radiators that may be in use.

Thanks guys!

1984ReturnsForReal_2

If you run it off the boiler a disadvantage to consider is that if your boiler fails you have no heat source.

typeractive

1984ReturnsForReal wrote: »

If you run it off the boiler a disadvantage to consider is that if your boiler fails you have no heat source.

Yeah - I've thought of that. Though this would be the case for the whole house as it will all be heated by radiators. Just means I'd have to have a supply of portable electric heaters, water bottles, big jumpers and some slippaz for me feet! lol

missile

Electric will be cheaper to install but more expensive to run.

We have a CH system supplying radiators in most rooms with underfloor heating in the lounge. Our lounge is quite large with floor to ceiling windows along one side. The underfloor heating works very well with no need for any supplementary heating.

If you do not want radiators on the wall, a cheaper alternative to underfloor heating would be to install kick space heaters. These can be electric >
http://www.kitchenappliancecentre.co.uk/electric-plinth-heater-2kw-in-stainless-steel.html

Tied in to your CH>
http://www.kitchenappliancecentre.co.uk/smiths-hydronic-kitchen-plinth-heater-kitchen-space-saver-5-ss5w.html

or dual fuel>
http://www.kitchenappliancecentre.co.uk/smiths-hydronic-electric-dual-kitchen-plinth-heater-kitchen.html

typeractive

Thanks missile!

Just to clarify, I don't want the underfloor heating to replace the radiators, as I still plan to install radiators in the kitchen. I want the underfloor heating in combination with the radiators. I guess it's an added luxury I would like to have, and only thought of it as I have the flooring all ripped up (just need to dig a little deeper).

Thanks for the input on which is cheapest to run. I'd rather pay a bit more to get the CH flooring system installed now and have cheaper fuel bills in the future. I also get the impression that the gas powered CH will be warmer than an electric element for some reason - I guess it feels a bit more industrial!

It won't be a massive area that I want to fill - just the middle strip really where people would be walking upon it. Under the cupboards and appliances would be unnecessaryin my opinion.


Keep the advice coming people!

Mankysteve

B&Q within the last few mounths discontinued and heavy discounted some under flooring heating stuff and replaced it with new products and the price has gone up again. I would go for the full sherbang and put in proper water filled pipes. Also might be worth looking at Heat pumps as they work very well with underfloor heating.

missile

typeractive wrote: »

Thanks missile!

Pleased to help. How big is your kitchen and what flooring do you intend laying?

Underfloor heating will not be so effective under tiles.

Bikertov

We have 'wet' Underfloor heating in our kitchen - with NO extra radiators, and it is great !

The floor itself, being a big slab of concrete, act as a big storage heater. It runs as a circuit off of out normal heating system. As it is at floor level, all the heat is even, rather than radiators that are just in one area. Also, being the floor, it feels warm to the feet, so giving more of a general 'warm' feeling.

As a wet underfloor system runs cooler than radiators, so it needs to heat the water less - this is then more efficient.

typeractive

Mankysteve wrote: »

B&Q within the last few mounths discontinued and heavy discounted some under flooring heating stuff and replaced it with new products and the price has gone up again. I would go for the full sherbang and put in proper water filled pipes. Also might be worth looking at Heat pumps as they work very well with underfloor heating.

Interesting. I've trecked over to the biggest B&Q store near me today to do a bit more investigating. Whilst I didn't come back with much more than I already knew I managed to try a sample out.

This is what I was looking for.

Now that system as advertised on the B&Q site looks more like the wet water system i.e. not electric filament. It said they had some in stock in the B&Q I went to - typically 15miles later they didn't... In fact the guy I spoke to didn't even know what I was talking about

However they did have this in stock. This was also what they had on sample. It felt quite good. When I enquired more about it all, the only good thing the chap was able to tell me was: the sales display example had a lot less adhesive applied than what you would need when doing it properly at home - quite good of him to tell me that (as obviously I couldn't see under that bit), he was hinting that the sample may not be as true a reflection of the product. The tiles used on display were approx 6/7mm...I think for my floor tiles I may end up using thicker? it's worth bearing that in mind folks - if anyone else is thinking of going down the same route.

Whilst looking at the product I was suspicious of how much heat the wire could generate as it's very thin.

missile wrote: »

Pleased to help. How big is your kitchen and what flooring do you intend laying?

Underfloor heating will not be so effective under tiles.

The room size will be approx 16ft by 10ft, though it will be the centre of this area that needs the underfloor heating as I will have kitchen cupboards and appliances dotted around the perimeter. Also I will be using floor tiles too. :S

Bikertov wrote: »

We have 'wet' Underfloor heating in our kitchen - with NO extra radiators, and it is great !

The floor itself, being a big slab of concrete, act as a big storage heater. It runs as a circuit off of out normal heating system. As it is at floor level, all the heat is even, rather than radiators that are just in one area. Also, being the floor, it feels warm to the feet, so giving more of a general 'warm' feeling.

As a wet underfloor system runs cooler than radiators, so it needs to heat the water less - this is then more efficient.

That's great news Bikertov, is there anything else you can tell me about the system? Do you know where it was purchased from, and how much it cost? Sorry for all the questions, and the work may have been carried out before you purchased the property, though your answer is exactly along the lines of what I have been thinking. Are you using floor tiles over the top of the heating? Any idea on the thickness of the tiles too?

I also would think that a 'wet' system as you call it would require less energy to heat. Does it run it's own 'circuit' specifically for the floor, or is it plumbed into the exisitng CH system (if that makes sense?) can you control it so you can switch the floor heating off and still make use of the radiators in the rest of t6he house?

Thanks everyone! I think such information will be really helpful to other MSE'rs!

missile

typeractive wrote: »

I also would think that a 'wet' system as you call it would require less energy to heat. Does it run it's own 'circuit' specifically for the floor, or is it plumbed into the exisitng CH system (if that makes sense?) can you control it so you can switch the floor heating off and still make use of the radiators in the rest of t6he house?
!

It takes the same ammount of energy wet or electric, but gas is cheaper.

You can install the system to work from your existing CH boiler but control the underfloor heating independently using a zone control valve and thermostat. If you want completely independent control you could install a second time clock.

Bikertov

typeractive wrote: »

That's great news Bikertov, is there anything else you can tell me about the system? Do you know where it was purchased from, and how much it cost? Sorry for all the questions, and the work may have been carried out before you purchased the property, though your answer is exactly along the lines of what I have been thinking. Are you using floor tiles over the top of the heating? Any idea on the thickness of the tiles too?

I also would think that a 'wet' system as you call it would require less energy to heat. Does it run it's own 'circuit' specifically for the floor, or is it plumbed into the exisitng CH system (if that makes sense?) can you control it so you can switch the floor heating off and still make use of the radiators in the rest of t6he house?

Thanks everyone! I think such information will be really helpful to other MSE'rs!

We had the UFH done as part of a MAJOR extension and refurb about 3 years ago, so difficult to give exact costs, but I would say it was around £2000 for an open plan kitchen diner area - about 8m x 4m of flooring. We have no 'normal' rads in that area.

The UFH is one of 3 heating zones in the house - upstairs (rads), downstairs (rads), and kitchen (UFH). Each zone is controlled by a Honeywell digital room stat, for independant temperature control. Nothing to stop you having a programmable digital stat - I did get some, but never got round to fitting them.

The UFH zone has a 'manifold' and control valve of its own, controlled by the room stat, and feeds into plastic tubing that winds round the floor area, and was pinned to a polystyrene base over the main slab, prior to being buried in a few inches of screed. The notes I still have from the plumber say 2 x 75m loops, 3200W output. The tiles are a 'reasonable' thickness 330mm square ceramic.

The specific UFH bits are housed in the bottom of a tall kitchen unit in the uility room, which uses any heat given from the pipework to make an 'airing cupboard'. There is a thermostatic valve (like on a rad, but not sure why, TBH) and a Grundfoss pump, wired into a small junction box. The manifold says 'uponor' on it - I presume this is these people ...

http://www.uponorhousingsolutions.co.uk/

The reason I say it uses less energy is that the water temperature that circulates round a UFH heating loop is cooler that for radiators, so therefore less energy to heat it up. And in general, Gas heating is cheaper than Electric. If you are thinking of solar water heating, I believe this works well with wet UFH due to the water temperature it can generate - too low for direct in to a rad, but just right for UFH.

I would say (my opinion only) that electric elements don't last as long in the end, compared to plastic piping buried in screed.

So, I'm no saying it was cheap, but as part of a bigger refurb you don't notice it so much !

As for comfort - it really is great. You can feel the warmth as you walk around, so that makes you feel warm. And it is much more of an even heat across the whole area, so you don't get the same hot spots like you do near a rad with cold as soon as you are 3 feet from the rad.

If I think of any more, I will post again later !