UFH - is it actually a good idea or not

[SteamyTea]

2 minutes ago, Indy said:

For those that have used UFH in their builds, do you use the same wet UFH throughout or do you split the bathrooms to have electric UFH (i.e. switch on when needed)?

 

Also, I assume that each room temperature is controllable using dedicated thermostats or can you only have 1 temperature set at the master control and through the house?

Really down to how YOU want it to be designed and operated.

 

There is nothing fundamentally different in wet heating system.

Hot water goes in one end, room is heated up, colder water comes out the other end.  How you split it is is more down to house design and lifestyle.

My small house, 5 room and a hall/landing, would work well with just one zone.

My Mother's house 11 rooms and a hall/landing, would probably need 6 or 7 zones, and a largish buffer tank as a lot of the time only 3 rooms are used (dining room has become a storage room).

[joe90]

19 minutes ago, Indy said:

For those that have used UFH in their builds, do you use the same wet UFH throughout or do you split the bathrooms to have electric UFH (i.e. switch on when needed)?

 

Also, I assume that each room temperature is controllable using dedicated thermostats or can you only have 1 temperature set at the master control and through the house?

Well I only have UFH downstairs all run from one room stat in the hallway, I have the flow turned up for  the lounge as that is the room we sit in, but find the whole house sits at a comfortable 21’. No heating upstairs but electric towel rads in both bathrooms and electric UFH in the ensuite. 

[Nickfromwales]

23 minutes ago, SteamyTea said:

Is it pleasant for them?

 

My Mother's house is at about 78 F 25.5°C.

Way to hot for me most of the time, but if I am just sitting down and reading it is lovely.

I installed a new gas combi for an old biddy and her spinster daughter. She had me go back, complaining that the living room would not get warmer than 21oC. My friend and I arrived and walked in, and within 60 seconds were both lathered up with factor 50 and stood there in pants and socks, as it was like a sunny day in Dubai!

The daughter had bought one of these weather station things from a petrol station and sat it on the marble fireplace, which had a gale blowing up it, and was on an ice cold outside wall ( mass produced bag of shit house btw ). I picked it up and placed it on the lady's coffee table next to where she was sat. As I was getting my arse chewed off about how the old boiler ( same kW rating, same radiators etc but now all flushed and with new TRV's ) was "so much better than the new one"......

After 5 minutes I pointed to the weather station doo-dah and it was showing 24.5oC.

We replaced the central heating system, but what we couldn't replace in that house was the lady's central nervous system  

[SteamyTea]

25 minutes ago, Nickfromwales said:

what we couldn't replace in that house was the lady's central nervous system

My Mother seems to be replacing hers all on her own.

Walking like she used to, still a bit of aphasia, but can get a witty retort out pretty quick.

And she remembered that she owed me £480 quid to get the shower fixed 2 weeks after the event.

Nowt wrong with old ladies, though not sure I want to grease myself up in my shreddies and dance for them, that is more @pocster's fantasy.

[Nickfromwales]

3 hours ago, SteamyTea said:

My Mother seems to be replacing hers all on her own.

Walking like she used to, still a bit of aphasia, but can get a witty retort out pretty quick.

And she remembered that she owed me £480 quid to get the shower fixed 2 weeks after the event.

Nowt wrong with old ladies, though not sure I want to grease myself up in my shreddies and dance for them, that is more @pocster's fantasy.

Funnily enough I offered to dance for them, purely as a distraction tactic whilst my mate stealthily inserted Boron rods under her chuffing sofa in an attempt to get the old dear up to the required 28oC   

[Onoff]

I can see UFH being super useful in a wet room situation after the little sods who can't be bothered to simply kick the towel they've just used around the floor to dry up any excess have been in there for a couple of hours. 

 

Or at least it will be once I connect it up...

[SteamyTea]

3 minutes ago, Onoff said:

I can see UFH being super useful in a wet room situation

Don't you just end up with a glaze of wee wee on the floor.

Actually, similar colour to my bathroom.

[Onoff]

13 minutes ago, SteamyTea said:

Don't you just end up with a glaze of wee wee on the floor.

Actually, similar colour to my bathroom.

 

Some people's grout is that colour by choice!

[SteamyTea]

Just now, Onoff said:

 

Some people's grout is that colour by choice!

Mine is, 2/3^rd up the wall.

[Gone West]

7 hours ago, SteamyTea said:

This is the problem of using percentages.

If he had left the door open then that decimal fraction may have dropped to 2%.

You would have to ask him but purely as a guess I would have thought he would have calculated it based on average winter ground temperature under the house, target indoor temperature and overall U factor for the floor. It's easier for a PH where the idea is to have the floor slab only slightly above indoor air temperature. If I were to ever build another PH, I would use the same method as before and use air to air ASHP heating.

[SteamyTea]

42 minutes ago, Gone West said:

You would have to ask him but purely as a guess I would have thought he would have calculated it based on average winter ground temperature under the house, target indoor temperature and overall U factor for the floor

Wish I could ask him.

But if it is based on his spreadsheet, then it is only looking at the fraction of total house losses, regardless of the energy source.

It also only uses mean values and not weighted values. So probably badly skewed, not sure in which direction though.

May have to make up a model sometime and see what comes out. I have an unused paving slab somewhere that can mimic a slab.

[Lord Greyabbey]

Some great advice and feedback here folks, very much appreciated.  Much to consider.  Having digested things and asked about, it also occured to me that there's no reason I couldn't do both i.e. UFH downstairs and radiators upstairs.  There's some funky looking rads out there these days.  Really it'll only be the kids upstairs anyway, and if it's zoned/thermostatic valves it'll do the job fine, and give somewhere to dry clothes (I know you shouldn't but I'm just being realistic!!)

 

I'm gathering prices for this, along with solar and heat recovery and ventilation systems, as it makes sense to do this now and future proof ourselves.