UF heating - some questions

[davejura]

We are looking at installing a wet UF system all round in our new build. First floor is living area and I am planning on using a screed pug mix on 100mm PIR insulation. I was thinking that between the 30mm screed and the PIR, I would have enough acoustic insulation between the floors, but am now doubting this. Any thoughts?

 

We have also temporarily put down 22mm chipboard flooring on the first floor to give a work platform. I have now read that the maximum floor thickness for efficiency of the UFH should be no more than 25mm. We are planning on engineered (probably oak) flooring and am wondering if we would be better going for 20mm planks and laying them straight on the joists. Again, looking for thoughts or experience! (Potential £1200 of chipboard flooring wasted!)

 

Finally, heated towel rails in the bathrooms. Is it worth integrating them or just have electric ones? Don't want to be turning the system on (ASHP) just to dry a few towels.

 

Just getting my head around everything again today after a couple of weeks away from it, and my head is fit to burst already! 🤣

 

[JohnMo]

We have UFH in bedrooms, wouldn't do it again, slow to heat up, slow to cool down, never the right temperature really.

 

Towel rads either electric only or dual fuel (electric/water).

 

Just do something like this for bedrooms, for heat and cooling.

 

https://coolenergyshop.com/collections/radiators-fan-coils

[Olf]

18 hours ago, davejura said:

I am planning on using a screed pug mix on 100mm PIR insulation. I was thinking that between the 30mm screed and the PIR, I would have enough acoustic insulation between the floors, but am now doubting this. Any thoughts?

 

We have also temporarily put down 22mm chipboard flooring on the first floor to give a work platform

 

100mm PIR on the 1st fllor sounds like an overkill to me: on the ground floor you have cold side at ~8'C, so you want to stay away from that, but on the 1st floor you have 'cold' side at ~21'C (= room temeprature downstairs, mind that warm air will lift so likely even higher) and any 'losses' that direction stay in the fabric of the building, so will make its way upstairs sooner or later.

 

Why not fit insulation between joists (wool, not PIR as that is bitch to cut and fit), that will also act as acoustic insulation and lay the UFH pipes on top of the chipboard flooring and screed as planned originally?

At least that's what I'm doing: 100mm Rockwool 45 between the joists, 22mm P5, Wunda EPS prerouted panels and thin fiber reinforced screed on top. I'm renovating, so limited in height and load hence Wunda system, you should have more wiggle room with choosing UFH solution.

[davejura]

Sounds like good advice. My fault for not researching acoustic properties of PIR boards! I would probably batten the 22mm P5 then lay 20mm engineered flooring directly on top with UF pipes in screed below. Should only raise the floor about 50mm. it's all a learning curve!