Limecrete Flooring - my experiences

[Socksitis]

What sort of pressure have you got the ufh at?

Strange that they have pressurised it with air and not hydraulically. How is it at keeping the pressure? I'd expect it to fluctuate quite a bit with temperature.

Are you using a 2:1 lime mix? Make sure your builders don't mix and pour it like concrete. It should be WAY firmer than that and should hold its shape pretty much when poured out of a bucket

Good luck! PM me if you need any help that can't wait on the open forum.

Hi,
all is well with the UFH, I know pressurising with air is not usual, but needs must I am afraid. As to the mix, yes 2:1 and yes crumbly is the best description. I am pleased to say I have very good builders, who may not have worked with lime, but have certainly done their homework. Also as stated on here, I cannot thank Mike Wye enough for their ongoing support. So the floors are setting, last of the floor area should be completed today. It is setting far quicker than any of us anticipated. We will put boards down next week and I can get back to the walls.

My only concern is where there is a concentration of pipes to and from the manifold - they all go through a section of wall, if there will be any cracking here? As we are heading towards better weather (allegedly) I have the luxury of being able to give the lime months to go off.

Next it is the screed for the slates. I look forward to reading your post Damon

 

[TheSpid]

So you went through a wall to get into the 2nd room and so use only one manifold?

We are looking at 3 rooms BUT they have steps up to each - house build on a slope left to right.

 

[TheSpid]

Now chatting with said above firm about this - many thanks they were in my saved list of people to contact anyway

 

[Socksitis]

Our UFH supplies 4 downstair rooms, but covers around 60m2, in 8 zones, but we ended up I think with 7 zones, all served by the same manifold.

 

[Helen Touzeau]

Thanks to the OP. This going to be interesting.



Vertically around the edge?
That may deny the limecrete some degree of perimeter support that it would have derived by keying into the walls, but breathability, hmm.

As to the slab, no. Any moisture will travel upwards through the slab and dissipate into the room. However, on the negative side it prevents the foot of the walls from breathing through the edge of the slab.
Whether that's a practical problem depends on how damp the walls are. From what you describe, it will still be an improvement.

What you really need is a breathable expansion material.
It's a good point. I would take it up with Mike Wye.

Ivor

I have used cork between the limecrete and the walls as an expansion strip and insulation. In the UK I understand 20mm is required. I would be interested in others' experience in laying the slab and if or what shuttering was use. My slab will be 30m/2