Under Floor Heating

[BlackAlys]

We have a really good chance of going for UFH in our renovation project and are looking for feedback on the water v's the electric - costs, efficiency etc.

All advice appreciated!

if you get electric UFH, you will start using it in the first winter, until the bill comes in, whereupon you will turn it off and never use it again.

This is quite normal.

We are getting wet underfloor heating. Running off the boiler. On a separate nest so we can run it independently from the rest of the house which is old and draughty….

We have two v small bathrooms with electric underfloor heating, that costs v little to run for a few hours in the day in the winter.

True @PigletJohn we got electric UFH, then got an OWL, not been switched on since 🤣🤣

Always gas unless you have a heat or air source pump being installed too.

We had wet system under slate flagstones - loved it no issues. I’d only consider electric if under a bathroom on only for a bit to warm floor, not to heat the room.

Had both electric and wet. Don't even consider electric. Wet all the way.

@PigletJohn

if you get electric UFH, you will start using it in the first winter, until the bill comes in, whereupon you will turn it off and never use it again.

This is quite normal.

🤣

Understood.
Thanks everyone.

Good chance we are staying with LPG/Calor or switching to oil. DH has no faith that an air source heat pump will be sufficient (3 story, 3 bathrooms) to heat the whole house.

Would love to have an element of remote control to the heating system. Can this be done?

Sorry - I realise that I've asked a totally separate question here

Hate our UFH. We have electric in upstairs bathroom which I love, and oil fired proper UFH downstairs. I find it isn’t responsive enough and I don’t want heating on all day. We use it as little as possible and mostly make do with wood burning stove and electric radiators instead.

Heat pumps can work well in well-insulated houses notwithstanding being 3 floors, be wary if your house isn't very energy efficient.

We have electric in our kitchen diner, hea within minutes, really good

Outer upstairs main bathroom has wet, come on with heating, nice when you gey out of bath or shower, can becslow for instant heat, but cheaper

We have water and it's bloody wonderful. I mean wonderful. Expensive to install but worth every penny.

And the cats agree

Love our UFH. Best thing we did when renovating our house. We have it in
large open plan living area and radiators in rest of the house. The two systems can be controlled separately and my husband added something last year so we can switch them on/off when away from the house.

@Jacketpandbeans

Love our UFH. Best thing we did when renovating our house. We have it in large open plan living area and radiators in rest of the house. The two systems can be controlled separately and my husband added something last year so we can switch them on/off when away from the house.

Fantastic - will look into this further. Thank you!

Thanks again, everyone.
I thing the wet system is the way forward but controlled on different thermostats hopefully.

Remote controlling is also a must for me.

We have a mixture. Electric in bathrooms which cost pennies as supplemented by towel rails run off wet system. Rads everywhere and retro fitted wet in kitchen conservatory and utility. All of the rads have valves liked to the wifi and all rooms controlled independently via an app. Kitchen etc all have separate stats again controlled via an app. Kitchen etc take longer to heat as run at a lower temp but once you get it right it’s brilliant. You must make sure you have plenty of insulation under the floor where the pipes are laid otherwise you’re just heating the ground!

We built an extension. We had wet UFH in the new part of the build.

The insulation standards need to be high, not just in the floor underneath but walls etc so new build is ideal. Ours is in a separate controller. It has to be as it needs to switch on at least two hours before the main house heating as it takes longer to heat up in winter. Conversely it switches off at 6pm and the room stays at a constant temperature.

It is a lovely different form of heat. Very gentle...not the sudden burst you get from radiators. DH isn't so keen on the heat on his feet when sat on a night but others love it

You can have the usual Hive/Tado remote controls but we didn't bother as we have such a consistent routine and was £500 to have them all fitted through the house.

Be aware...if a new floor with screed, it MUST dry out. Usually it takes 1 day over MM of screed. Ours had I think 60-80 mm screed so should be left that same number if days although with the UFH you can start turning it on after a month and force drying it. We didn't bother until nearer the end as we had other building work going on so let it dry as naturally as possible.

Make sure you have a plumber that is experienced in installing UFH. Many are not.

It is supposed to be 20% more efficient than normal heating. Part of that is the lower temp it works at. We didn't notice a difference in our bills but we had a much bigger space.

What I would recommend depending on your boiler is consider replacing it. We didn't and couldn't have had it done for £400 plus the cost of the boiler £1200) at the same time. We didn't and did it this year. What a mistake in hindsight. It cost £2400 but the saving in gas is amazing. DH is reckoning we are going to have reduced the gas bill by circa £3-400 per annum which would have paid for it in 4-5 years. UFH is particularly suited to the newer type boilers as it needs water going in at a lower temp and uses a mixer to achieve that. Our boiler is slightly oversized but is able to modulate the gas up and down automatically whereas some cheaper ones it is set

A friend inherited electric UFH and had the exact experience @PigletJohn describes lol. Frankly should be banned installing it!

Depending on your flooring, there may not be room for water piping. My entire ground floor is concrete, so the only choice for underfloor heating was to lay the thin electric mat type and tile on top.
It made a huge difference to the warmth - the kitchen used to be freezing, despite a large radiator.
I don’t find it expensive to run - I use it 24/7 in winter, controlled from my phone and a thermostat/timer, so it goes down to 15C at night but is on at 20 to 25C during the day.
I turn it off in the summer, along with the gas central heating, and just use the boiler to heat bath water.
My kitchen is a barn style room, with an 11 foot high ceiling, so it really benefits from UFH. The radiator heat just used to rise to the ceiling without warming the room at ground level. And the concrete floor sucked heat away.

This is invaluable stuff.

I'm going to look for another plumbing engineer tbh - the one that visited the site said straight away that the existing 15 year old boiler is fine and then started mumbling a bit about being 'on the cusp' of needing changing when I pointed out that the plan is for 3 bathrooms/shower rooms over 3 different floors.

He didn't inspire confidence.

"3 bathrooms/shower rooms" will do best with an unvented cylinder, which could be a significant plumbing change.

It would need quite a powerful boiler to heat it from cold in a reasonable time.

@PigletJohn I really appreciate your input.

We have 3 DD's and I keep trying to gently tell DH that it's pointless us forking out for 3 shower rooms if they cannot actually be used at the same time. He keeps saying, "If we don't NEED a new boiler, we shouldn't get one" despite me reminding him that the ageing boiler was fit for purpose for a 2 bedroom cottage with an elderly warhorse lady who washed in cold water!

We completely renovated our house, put in wet ufh throughout, and absolutely love it. It took a while to get used to as it's not controllable in the usual way, but once you trust it to just go on and off when needed, there is just a gentle constant temperature at all times, and every room in the house is always pleasant, there are no drafts anywhere. The added bonus is not having radiators, so furniture can go anywhere.
We pay £120 per month total for gas and electric. Wouldn't be without it.

try to find out the power of the boile. A 20kW boiler is enough for most houses, a 30kW will do quite a large, badly insulated old house (or a combi is usually about 30kW because of the way they work).