Liquid screed drying time

[Walshie]

Hi,

I’m having liquid screed poured next week.

Build-up is:

Block & beam floor

1200g DPM

150mm insulation

1200g DPM

UFH

50mm liquid screed

 

Any thoughts on drying time before it would be safe to lay underlay and an engineered timber floor?

 

Is it worth running a dehumidifier for a few days?

 

Any insight would be really helpful.

 

Thanks,

W

[Mr Punter]

It depends on temperature, airflow and screed type.   Allow 1mm per day as a guide.

[Clark Kent]

Sorry can’t comment on drying time  but I’d swerve the underlay and bond directly to the screed for heat transfer. 

[Walshie]

Hi,

That's interesting - I hadn't really considered the heat transfer would be impaired by the underlay?

 

[JohnMo]

Underlay will kill UFH performance, it's normal not to float a floor on UFH, it's more normal to bond the floor down.

[Thorfun]

you can get underlay suitable for ufh and wooden flooring.

 

as above to drying times....is it cemfloor or anhydrate liquid screed? i think 1mm per day is excessive for liquid screed. i know that's the value for dry screeding but i thought liquid was quicker?

 

luckily for us we're really slow at everything and our screed was down for a long time before we covered with tiles and wood! 🤣

[Barnboy]

If its an anhydrite screed like ours then 1 day per mm minimum,  comission you ufh too and then moisture test.

Ours was down fo far longer and I couldn't believe the amount of moisture that still came out of it when I commissioned the ufh, our windows were dripping with condensation, you dried them and they were dripping again before you'd finished each window.