Levelling current concrete floor

[PeterW]

Floors don’t work like that - they act as a panel even with point loads (up to a certain point) so if you use sand cement to level, it will go hard. Then add marmox and the carbon foil and then laminate it will be fine. 
 

Tbh I wouldn’t be leaving out any areas in a room like that so you can move things about in the future. The carbon film stuff is fairly good at self regulating so you shouldn’t get any problems. 

[TheMick]

53 minutes ago, PeterW said:

Floors don’t work like that - they act as a panel even with point loads (up to a certain point) so if you use sand cement to level, it will go hard. Then add marmox and the carbon foil and then laminate it will be fine. 
 

Tbh I wouldn’t be leaving out any areas in a room like that so you can move things about in the future. The carbon film stuff is fairly good at self regulating so you shouldn’t get any problems. 

Do you mean not running the UFH under where the desk will go? 

 

I only thought about doing this as the instructions online seem to say not to put UFH where units or freezers and the like are. 

[PeterW]

3 hours ago, TheMick said:

Do you mean not running the UFH under where the desk will go? 

 

I only thought about doing this as the instructions online seem to say not to put UFH where units or freezers and the like are. 

That is different - you don’t want to be applying heat under cupboards where food may be stored, or making fridges or freezers work harder. This sounds like a fairly open flexible space so just install the heating up to the most suitable point in the room - with the heat mats you’ll probably need to look at the best layout for a 10m mat which may leave out around 100mm from each side which isn’t an issue. 

[TheMick]

On 18/08/2020 at 17:04, PeterW said:

Yes - there will be enough moisture in the sand for the cement to go off. Makes it easier to level this way. 

Hi Peter, I'm back again! Haha

 

Last question I hope.

How long would you wait until putting the tile backer boards on top of the dry mix? 24hours?

 

Thanks for both yourself and Nickfromwales assistance on this. 

[PeterW]

TBH I would leave it a day or two, and just use a cheap polythene slip layer as a DPC to stop the sand getting churned up. If you want it yo go off quicker then just mist it with a hose. 

[TheMick]

1 hour ago, PeterW said:

TBH I would leave it a day or two, and just use a cheap polythene slip layer as a DPC to stop the sand getting churned up. If you want it yo go off quicker then just mist it with a hose. 

So put this polythene dpc on top  of the layed sand cement dry mix even though the backer boards are then going on top and can be a DPM? Tah

[PeterW]

Yep - just stops the sand and cement ending up between the boards. 

[TheMick]

2 hours ago, PeterW said:

Yep - just stops the sand and cement ending up between the boards. 

So I'm not waiting for the mix to go off hard and solid like a water added mix? 

Alot of articles on the Internet suggest sticking the backer boards down with flexible tile adhesive though. Cheers

Edited August 27, 2020 by TheMick

[TheMick]

On 27/08/2020 at 17:00, TheMick said:

So I'm not waiting for the mix to go off hard and solid like a water added mix? 

Alot of articles on the Internet suggest sticking the backer boards down with flexible tile adhesive though. Cheers

You hiding out Peter? ?

[PeterW]

@Nickfromwales can comment on how to lay the boards but I’d want it to go firm which is only a couple of days.