UFH which one best for wooden and concrete floor?

[SpecialK]

But I’m trying to avoid screed and like to use 18mm overlay boards and tile it?

You need some kind of screed top layer otherwise it may be wonky. Slab concrete and insulation will be hard to get exactly level.

I would seriously consider converting the wood floor to concrete so you can do the whole lot the same?

Maybe speak to the manufactures of the overlay board and see what they suggest?

 

[Nozzle]

To avoid disapointment, you need thick insulation - not those thin foam rolls as the U values are frigged to look high in the lab tests. With this in mind, you might consider that the concrete need digging up anyway.

Nozzle

 

[Madrab]

Yes, you will need a self leveling layer to ensure it's is flat and level before the overlay. With the ones I used the overboard system on, the concrete was already leveled so all that was needed to do was DPM then fix the wood to the floor.

The original floors were leveled concrete, DPM, 20mm styrene then P5 with the floor on top of that. We lifted the chipboard, and removed the 20mm styrene. Replaced the DPM then fixed the P5 to the crete base. Then the overlay boards were fixed to the P5, UFH fitted and then the final floor layer was added.

Any reason you don't want to use a traditional screed, you certainly have that option with that amount of space.

I must admit though, the overlay board approach is very good. Fast heat up times and no need for protracted running to maintain a thermal mass.

 

[Naresh2022]

Any reason you don't want to use a traditional screed, you certainly have that option with that amount of space.

Like to use the new best technology and at the same time reduce cost

Below panels are Dry Screed Overlay boards.

 

[SpecialK]

Remove the wood floor and add PIR insulation between the joists. Use chipboard then the overlay boards.

With the concrete floor make it up as I mentioned earlier with the UFH pipes embedded in to the screed - It its much cheaper than the boards and will act as a big heatsink. UFH pipes in screed are surrounded so transfer the heat better and will spread the heat out so its even across the floor. It will be warm for many hours after the heating if off but will take longer to heat up unlike the overlay boards.

Have traditional or liquid screed over the UFH pipes poured to the same level as the overlay boards on the wood floor. Traditional screed can be "shaped" to the overlay boards if required.