Under floor (tile) heating

[LetsTryAgain]

Hi all.

Having to do some under floor work in the kitchen and using the opportunity to replace the carpet tiles with something a bit nicer.
Tiles will be going down after the work is complete and I'm wondering if you can get decent enough under floor heating to go through decent thickness tiles?
Any and all help appreciated.

Thanks, Stuart.

[biggiles]

Tiled floors are ideal for under-floor heating! Almost every five-star hotel bathroom in the world will have tiled underfloor heating.

[LetsTryAgain]

biggiles said:

Tiled floors are ideal for under-floor heating! Almost every five-star hotel bathroom in the world will have tiled underfloor heating.

Does it matter that they're quite thick?
Well, I suppose they're maybe 1/3 of an inch thick so that's not terrible.
Basically, I don't want to go to the expense of putting it all in if it's not going to be felt in the room.

[guindilias]

It will go through any tile thickness no problem, it's just a matter of setting it to come on earlier and turn off earlier depending on the thermal mass of the tiles above it - which you will find out once it's all done.
Make sure you have insulation underneath it though, or the electric bills will be even more extortionate than they will be anyway - there is no such thing as cheap and effective electric heating.

[LetsTryAgain]

guindilias said:

It will go through any tile thickness no problem, it's just a matter of setting it to come on earlier and turn off earlier depending on the thermal mass of the tiles above it - which you will find out once it's all done.
Make sure you have insulation underneath it though, or the electric bills will be even more extortionate than they will be anyway - there is no such thing as cheap and effective electric heating.

Thanks for the reply.
I have seen water underfloor heating kits, which I assume run off the central heating.

Do you think this will be a better (cheaper!!) option?
I am 'in' the central heating system anyway as a result of the work I am doing to the kitchen, so it wouldn't be much trouble.

I have had to remove a radiator, basically. So now wondering what would be the best way to heat the kitchen in the future.

[Royal Jelly]

I’ve got electric UFH throughout the downstairs of my cottage (2 rooms, 2 wifi thermostats). It’s under fairly thick tile, but on insulating boards. Heat will get though tile, it just takes (in our case) 30 mins or so..

It’s a converted stable so solid concrete floors, so wet UFH would have been quite the job. It does take longer downstairs on the solid, cold concrete floor compared to the suspended timber bathroom floor upstairs (same tiles). I can flick the bathroom floor on before I get in the shower and it’s lovely when I emerge from it 10 minutes later..

My only gripe is that the insulating boards went down on a slightly uneven floor (was cruddy carpet prior), so when the tiler arrived, he needed to pour down a bit of levelling screed, which means that in a couple of spots the UFH is slightly less warm as it’s buried further down. So I’d advise ensuring the floor is exactly levelled before laying thermal boards down - sounds obvious, I know!

I’ve never experienced wet UFH, though I suspect it’s a fair bit more to install and a fair bit less to run. I will certainly give the thumbs up to our elec version though. We have 3 stats via a WiFi hub that we can control. We live overseas so it’s nice to flick it on periodically to keep the place warm and dry, and of course in the depths of winter it’s a lovely thing to set on for our return.

It’s a wonderful even heat. It’s very sad, but in the depths of winter I love to be barefoot inside.

As for the cheapest way to run it, I’m yet to really experiment because we don’t live there, but I suspect that due to the lag time where the pads are heating through the tile, it’s cheaper to set a sensible temp and leave it on, rather than setting it on twice a day or whatever.

My Heatmiser thermostats have 2 probes, an ambient and a floor probe. It switches to the (always cooler) floor probe when the matts turn on, which is a bit weird, but you get used to how best to manage it.

Any questions, I’ll be happy to share my experience.

Edited by Royal Jelly on Monday 6th July 06:26

Edited by Royal Jelly on Monday 6th July 06:29

[guindilias]

LetsTryAgain said:

Thanks for the reply.
I have seen water underfloor heating kits, which I assume run off the central heating.

Do you think this will be a better (cheaper!!) option?
I am 'in' the central heating system anyway as a result of the work I am doing to the kitchen, so it wouldn't be much trouble.

I have had to remove a radiator, basically. So now wondering what would be the best way to heat the kitchen in the future.

It will certainly be a cheaper to run system - hugely cheaper - but more expensive to install. They do run off the central heating, so will need a plumber - what kind of floor, timber or concrete?
Electric heating is cheap to buy, and cheap to install as it is basically put down as part of the tiling process.
But as you have removed a radiator (if you look for the size you removed and find out what kw rating it was, that will give you a rough idea of what you need to replace with UFH of either type), that will mean much larger bills on electric UFH, but little change in the bills if you go with a wet system.
Your floor type may dictate the choice though!

[LetsTryAgain]

Good afternoon gents.

Thanks for taking the time to respond; some very helpful points raised and questions asked!
Concrete floor, so I suppose I’m stuck with electric UFH in reality.
I’ve just ‘dug’ a 10” wide by 8” deep hole in that so I really don’t want to be doing that for the rest of the floor.
I’ll have another read or two through the responses and go from there.

Thanks again.

[guindilias]

Is it a new enough house to have decent insulation under the slab, or is it concrete then soil?
You can have a groove for wet UFH cut into the slab, but that's only really worth doing if you have insulation already there - otherwise it'll be a big difference in floor height, or a bit of a bodge with ally heat spreader pates that will still just dump most of the heat into the ground.
https://www.outsourcedenergy.co.uk/in-cut-underflo... - never used this lot, just an example of how it can be done.

[TA14]

LetsTryAgain said:

Good afternoon gents.

Thanks for taking the time to respond; some very helpful points raised and questions asked!
Concrete floor, so I suppose I’m stuck with electric UFH in reality.
I’ve just ‘dug’ a 10” wide by 8” deep hole in that so I really don’t want to be doing that for the rest of the floor.
I’ll have another read or two through the responses and go from there.

Thanks again.

I would have thought that a 10' wide radiator would make a significant heat contribution unless you have a very large room.

[guindilias]

Inches < feet.

[TA14]

guindilias said:

Inches < feet.

Oops - just put a normal rad back then.

[guindilias]

But he had to take out the radiator, so I'm assuming there isn't the wall space to fit one.

[LetsTryAgain]

guindilias said:

Is it a new enough house to have decent insulation under the slab, or is it concrete then soil?
You can have a groove for wet UFH cut into the slab, but that's only really worth doing if you have insulation already there - otherwise it'll be a big difference in floor height, or a bit of a bodge with ally heat spreader pates that will still just dump most of the heat into the ground.
https://www.outsourcedenergy.co.uk/in-cut-underflo... - never used this lot, just an example of how it can be done.

Thanks for all the help.
Nope, 30's house, and I've dug it out and got to soil.
The pipes (feed and waste) are sat within a 4 and a half inch pipe with two 90 degree ends so i can refill the hole with concrete but both the pipes remain free from it.

The point of removing the radiator is because it takes up space for 3 'appliances' which i'd rather have stuff in than big old radiator which I can't put anything in front of.

Will post/read more etc later.

• Later*

I was going to fit the radiator which I removed to the opposite wall, vertically.
The main reason for all this work is that due to an earlier extension, the layout isn't the best for the size of the room.
So rather than lose 3 appliance spaces under the counter due to a radiator, it's been removed.

Also, hadn't given the insulating boards any thought, to stop the heat just disappearing into the ground below!

Edited by LetsTryAgain on Tuesday 7th July 06:31

[Andeh1]

I'll try and dig back through my previous posts on this subject. We retrofitted overlay wet UFH across kitchen and two bathrooms. I have posted extensively on this subject a few times in this forum.

Kitchen was a couple of grand, prob 4x cosy of electric to install and a 40mm height build up but made nigh on zero cost to the heating but gave us 30sqm of heating without radiators.

. The bathrooms were probably 1k each to fit but Ufh is sublime, and I hate electric running costs.


. Edit:
As has been said, insulation is critical! If you can't fit in a minimum of 10-15mm under the electric UFH don't bother at all. You will need spend a fortune warming up your subfloor as much as you warm the tiles.

[LetsTryAgain]

Thanks, that'd be appreciated.
Where did you get your stuff from?
Is it possible to get a 'turn key' kit, as it were?

I've found this site, but it's difficult to know what items I need!
More research required I think.

Edited by LetsTryAgain on Tuesday 7th July 21:08

[Andeh1]

I bought most of the kit from "the underfloor heating store" l. They supplied the low profile insulated sheets with pipe grooves, pipe, did the room layout, manifold etc...

[LetsTryAgain]

Andeh1 said:

I bought most of the kit from "the underfloor heating store" l. They supplied the low profile insulated sheets with pipe grooves, pipe, did the room layout, manifold etc...

This sounds like a 'wet' kit, is that right?
I like that the LP insulated boards had recesses in them for the pipes.
That will help keep the 'raise' in the heigh to a minimum.
What sort of size room did you do and is it any good?

Thanks, LTA.

[Fatboy]

You want polypipe overlay - wet ufh....

They'll work out what you need, just fill out a form on the website, used it myself, very pleased with it...

https://www.polypipeufh.com/our-systems/over-the-f...