WET UFH or Traditional Rads!?

[richo106]

Hi

 

We are just starting some major renovations on a bungalow we have just purchased, it will it extending up and to the side

 

It is all timber joists and floorboards (apart from one room which is concrete) It will be heated by a oil fired combi boiler

 

In early plans was to have wet UFH to heat downstairs but a couple of local plumbers who I've had round have been quite negative of it

 

Obviously it is more expensive to install

 

They also mentioned it doesn't heat the house as well as radiators, it costs more to run, have trouble with the valves

 

Needs more space for the valves and also running costs of a thermal store

 

So I was after some more professional opinions and opinions of people who have fitted them in their houses as we are in a bit of a quandary now

 

Thanks

[Temp]

How well insulated will it be and what condition are the floors in? Are you considering replacing them with concrete floor? If so then wet UFH is an option. I think otherwise I think I would stick with rads.

 

1 hour ago, richo106 said:

They also mentioned it doesn't heat the house as well as radiators, it costs more to run, have trouble with the valves

 

Needs more space for the valves and also running costs of a thermal store

 

Running costs of any system are dominated mainly by how well insulated the house is. If you had a perfectly insulated house you wouldn't need heating.

 

Correctly installed UFH is perfectly capable of heating a house well. We have wet UFH and love it. Nice warm stone floors in the bathrooms for example.

 

 If the house is badly insulated and you are planning on turning the heating off when you both go out to work then perhaps rads are a better bet. If its reasonably well insulated and somebody will be home most days then UFH gets my vote.

 

Our system has performed faultlessly for 13+ years. No "trouble with valves" whatsoever. Personally I would avoid fancy self balancing UFH valves but the regular type are just fine. 

 

With an oil fired combi boiler and UFH I would recommend a buffer tank of some sort. That could be a thermal store but need not be. 

Edited July 15, 2021 by Temp
remove white space

[Nickfromwales]

A lot of UFH gets installed badly, so the comments from your plumbers don’t reflect well on them I’m afraid  They should have told you what you need to do to have a successful UFH installation, not just spout negatives!

Have you bought the combi yet? If not, buy a system boiler instead and run a thermal store ( 180-210L ) and get bags of hot water from that, way more than from a combi too. The TS will also provide a pair(s) of tappings for the lower grade heat you need to feed the UFH with. 
The mention of a store is because of the oil boiler, because oil burners cannot modulate ( go to a small flame for low output like a gas boiler can ) so you get 0-100-0% “all or nothing” output which needs to be captured over a long ( economical ) burn, and then drawn down via the store.

The downside of the TS is it needs to be hot pretty much 24/7 to provide hot water on demand, but the difference in hot water supply will be huge vs a combi.

Bottom line is, you’ll need a buffer tank or TS, particularly with retrofit UFH. 
Draught proofing the house, 3G doors and windows, and insulating as well as you can will reduce the amount of heat you need for the house to stay at 21oC, so UFH can and will work we’ll if you don’t fail to prepare. 
Get new plumbers too. ?

 

 

[richo106]

14 hours ago, Temp said:

How well insulated will it be and what condition are the floors in? Are you considering replacing them with concrete floor? If so then wet UFH is an option. I think otherwise I think I would stick with rads.

 

 

Running costs of any system are dominated mainly by how well insulated the house is. If you had a perfectly insulated house you wouldn't need heating.

 

Correctly installed UFH is perfectly capable of heating a house well. We have wet UFH and love it. Nice warm stone floors in the bathrooms for example.

 

 If the house is badly insulated and you are planning on turning the heating off when you both go out to work then perhaps rads are a better bet. If its reasonably well insulated and somebody will be home most days then UFH gets my vote.

 

Our system has performed faultlessly for 13+ years. No "trouble with valves" whatsoever. Personally I would avoid fancy self balancing UFH valves but the regular type are just fine. 

 

With an oil fired combi boiler and UFH I would recommend a buffer tank of some sort. That could be a thermal store but need not be. 

I think we will be sticking with the joists and floorboards etc, but I will be taking up the floorboards to insulate so I don't this would be an issue if we was to go with UFH

 

I just don't know which way to go for the best

 

This being said regarding insulation the rest of the house, I could overboard with insulation to increase the insulation on the exterior walls