Wet UFH: low profile vs screeded

[harrybertrand]

What are the disadvantages of low profile wet UFH boards, in comparison to conventional pipe-in-screed systems (those in which there is at least 50 mm of screed)? Would these disadvantages be as relevant in a small bathroom (wet room) application, for which the total floor area is less than 10 m2?

 

[ShaunCorbs]

Not much thermal mass and not much insulation below but they warm up faster

 

[harrybertrand]

I am planning to insulate either way. If using low profile, vacuum insulated panels.

Is a lack of thermal mass relevant if the UFH is only for a small space, that isn't normally in use? I.e. time it to come on for 1 or 2 hours first thing in the morning?

 

[ShaunCorbs]

No would only effect it when it’s off eg cools down quicker

 

[harrybertrand]

Just wondering if there are any other aspects to be aware of if going for low profile vs traditional screed? Must be reasons why it isn't more popular because at the moment, to me it looks like a get out of jail free card for retrofits.

 

[oz-plumber]

Just wondering if there are any other aspects to be aware of if going for low profile vs traditional screed? Must be reasons why it isn't more popular because at the moment, to me it looks like a get out of jail free card for retrofits.

Exactly......

Smaller diameter pipe and pipe spacings closer.

PITA control in a small area unless you have other areas you can control on the same manifold

 

[harrybertrand]

Oz-plumber thanks, but I'm not sure if I follow. Excuse my ignorance, aren't you describing just a sizing issue? What do you mean exactly by control, and why would the small bore pipes and small area make it inherently more difficult? I'm not sure I see the need for a room thermostat controlling just the UFH in the bathroom, just have a timer and water temperature set point instead.