UFH - concrete slab above or below?

[Dan Robinson]

For what it is worth the experience of a friend who installed UFH

When the children were young and [their mother] was at home most of the day UFH was ideal but still had to be supplemented when the wather was cold. When the children were older and [their mother] went back to work the house was empty most of the day. Getting the start time correct in order to have a warm house in time for [mum] and the children coming home was difficult. A fast response heating source was needed and to achieve this we have installed radiators.

To be fair that house is a converted old building and not well insulated. A well insulated and air tight box of a house might be well served by UFH as the only heat source with floor temperatures warm enough to keep the house warm while still being cool enough to walk on in comfort.

A calculation involving heat loss, effective floor area and required floor temperature will give an idea of whether UFH alone is going to be sufficient while still being comfortable to stand on

Your friend's system was poorly designed and installed

 

[PullerGas]

More drivel from the poorly informed & inexperienced Google Warrior. Poorly insulated houses always require a floor sensor with UFH. The ratio can easily be set on both time & temperature.

Your imagery friend had a cowboy install BG.

 

[bernardgreen]

Your friend's system was poorly designed and installed

Your imagery friend had a cowboy install BG.

I will pass your comments on to the company who designed and installed the system.

 

[Dan Robinson]

Please do.

 

[bernardgreen]

Your friend's system was poorly designed and installed

You cannot make that statement without seeing the installation.

Could you explain how a better design would have removed the time delay caused by the thermal mass of the floor structure. Only by reducing the thermal mass or overdriving the heat imput can that delay be reduced but it is still not economically possible to accurately predict the delay. A comprehensive array of temperature sensors in the thermal mass of the floor will assist in the calculation of when the heating should be started to have the room at the required temperature by the required time. The complexity and cost of the "perfect" control system is the down side of domestic UFH

 

[PullerGas]

Please do BG

 

[PullerGas]

You cannot make that statement without seeing the installation.

Could you explain how a better design would have removed the time delay caused by the thermal mass of the floor structure. Only by reducing the thermal mass or overdriving the heat imput can that delay be reduced but it is still not economically possible to accurately predict the delay. A comprehensive array of temperature sensors in the thermal mass of the floor will assist in the calculation of when the heating should be started to have the room at the required temperature by the required time. The complexity and cost of the "perfect" control system is the down side of domestic UFH

I completely concur with Dan.

BG given you've no understanding of a UFH system, why argue with Dan & I?? Together we will have about 50-60 years experience in the game, where as you have zero!! Why do you repeatedly make a complete c.nt if yourself on this forum??

 

[bernardgreen]

Being derided by you on this forum is a trivial inconvenience. Your attitude and language say a lot about you.

I wonder what your reaction would be if, for example, unbeknown to you the technical director of a heating company had started a discussion with you on this forum and discounted your opinions as worthless. Most likely you would be abusive and derogatory up until the point in the conversation when he ( or she ) identified his ( or her ) role in the heating industry.

At least with your identity hidden from view you will not lose customers who would not employ a plumber with the attitude that you have in the public area of this forum.

 

[Dan Robinson]

You cannot make that statement without seeing the installation.

Could you explain how a better design would have removed the time delay caused by the thermal mass of the floor structure. Only by reducing the thermal mass or overdriving the heat imput can that delay be reduced but it is still not economically possible to accurately predict the delay. A comprehensive array of temperature sensors in the thermal mass of the floor will assist in the calculation of when the heating should be started to have the room at the required temperature by the required time. The complexity and cost of the "perfect" control system is the down side of domestic UFH

Simple really. It's about the correct application of technology, controls, materials for the job.

A heatloss calculation, a look at the draft situation, then plumb as required. Could be a mixed emitter zone, but either way, if they're constantly having to interfere with it to get it working then it is deficient in some way.

Some things you can't Google. And, frankly, after the morning I've had with some old fart in a meeting wittering on about how his system is better because [insert some booloocks gleaned from the Internet /google/brochure] I'm not in the mood.

 

[shambolic]

So my underfloor has built in optimum start and I set it for 20 deg at 630am.
Now if at 5am it's only 10deg it works out that it needs to come on but if at 5am it's 18deg then it might not come on till 6am.
Same with evening I have a set back temp and an on temp and it uses a smooth curve between these so as not to delay coming on or overshoot temps.
Simple if designed right and customer knows how to work it.
Ps I also have 12 rads on this system too on a separate zone.

 

[Dan Robinson]

Have a HM80 on my UFH and the weather comp works quite happily on the rads as well as the UFH.... With the miles of the stuff we have installed in houses with "high maintenance" customers, if it didn't work then I am sure I would have found out about it now.

Brother has it in his 450 year old farmhouse with wattle and daub walls. With rads on the upstairs. Wonder how he copes.... Let me just check on his home automation app.

 

[shambolic]

So bennyboy tell me how rads will heat my lounge evenly?
2.5 storey height and over several rooms?
Go on tell me?

 

[Dan Robinson]

Isn't going to happen is it really. Much like our ground floor - 70 square metre open planned living area in a U shape and a long bare wall. Rads would look crap and leave massive cold spots.


Brother's house is bob on BTW .

 

[shambolic]

Nurse has took Bennys internet privileges away again as he's gone.

 

[Dan Robinson]

I think Google have rationed him and Hard-On. Bedfordshire gets brownouts when he's trying to be a clever dick,.