Cemfloor - Tiling - Decoupling Matt?

[Antec123]

Hi, we have had our kitchen screeded with "Cemfloor Level+ with Fibers", 20m2 and at 25mm depth, this was yesterday.

 

Wet UFH under it, with XPS boards (with grooves for the pipes)

 

We were told we can walk on it after 24 hours (24 hours has passed by and yes its walkable and have opened the windows and door for ventilation) and tile after 3 weeks, we are going to tile on it with 1200x1200 tiles, which came with enough Kelmore MoreFlex S1 Standard adhesive for the tiles.

 

Ive read Cemfloor has no Laitance so we will not need to remove the dust? thats a relief! 

 

As we have spent a pretty penny on these tiles, I was thinking of using Dural Durabase CI++ decoupling matt due to its vapour control, do you think it's wise? will cost around £170 for 20m2, or are there any cheaper ones I can use? I will need to buy some adhesive for it, which is the go to for matting? and how many bags do I need?

 

Also in your option, how soon can Cemfloor be tiled on? how do I know when the floor is completely cured?, does it need priming before the decoupling matt? 

 

Thanks

 

 

Edited Wednesday at 16:59 by Antec123

[Conor]

We tiled directly on to our cemfloor, no issues. No grinding, no decoupling mats. Tho our drying time was a lot longer, 3 months for 50mm. The general rule is 1 day per mm, for standard adhesive directly on to screed. You can use green screed adhesive and tile within days.

Edited Wednesday at 18:33 by Conor

[nod]

1 hour ago, Antec123 said:

Hi, we have had our kitchen screeded with "Cemfloor Level+ with Fibers", 20m2 and at 25mm depth, this was yesterday.

 

Wet UFH under it, with XPS boards (with grooves for the pipes)

 

We were told we can walk on it after 24 hours (24 hours has passed by and yes its walkable and have opened the windows and door for ventilation) and tile after 3 weeks, we are going to tile on it with 1200x1200 tiles, which came with enough Kelmore MoreFlex S1 Standard adhesive for the tiles.

 

Ive read Cemfloor has no Laitance so we will not need to remove the dust? thats a relief! 

 

As we have spent a pretty penny on these tiles, I was thinking of using Dural Durabase CI++ decoupling matt due to its vapour control, do you think it's wise? will cost around £170 for 20m2, or are there any cheaper ones I can use? I will need to buy some adhesive for it, which is the go to for matting? and how many bags do I need?

 

Also in your option, how soon can Cemfloor be tiled on? how do I know when the floor is completely cured?, does it need priming before the decoupling matt? 

 

Thanks

 

 

Scrape any loose material off the top 

Prime with SBR 12 hours before if possible No need for matting 

[Antec123]

8 minutes ago, nod said:

Scrape any loose material off the top 

Prime with SBR 12 hours before if possible No need for matting 

Thank you, would you still say 3 week is long enough to wait? how does one actually know its cured? or just play by ear 

Edited Wednesday at 18:51 by Antec123

[Antec123]

17 minutes ago, Conor said:

We tiled directly on to our cemfloor, no issues. No grinding, no decoupling mats. Tho our drying time was a lot longer, 3 months for 50mm. The general rule is 1 day per mm, for standard adhesive directly on to screed. You can use green screed adhesive and tile within days.

Thank you, good to know matting not needed!

[Antec123]

Looking at the Guidelines for Cemfloor UFH, it says can start UFH commissioning after 7 days: https://cemfloor.co.uk/wp-content/uploads/Datasheet_Cemfloor-Therm-UFH-Guideline_2020.pdf @nod whats your take on this?

[nod]

15 minutes ago, Antec123 said:

Looking at the Guidelines for Cemfloor UFH, it says can start UFH commissioning after 7 days: https://cemfloor.co.uk/wp-content/uploads/Datasheet_Cemfloor-Therm-UFH-Guideline_2020.pdf @nod whats your take on this?

I can only go from experience 

I tile dozens of these floors each year without any Matt 

The floor matting has only become popular over the last 20 years

It was once the norm to screed in the morning and tile in the afternoon 

[Antec123]

9 hours ago, nod said:

I can only go from experience 

I tile dozens of these floors each year without any Matt 

The floor matting has only become popular over the last 20 years

It was once the norm to screed in the morning and tile in the afternoon 

Thank you. Have you ever commissioned UFH with Cemfloor? Is the 7 day start time realistic?

[Kelvin]

What our tiler wanted was for us to run the ASHP in floor drying mode which, from memory, took two weeks. It slowly heats up the floor then slowly cools it back down again. It then had to be off for at least 24 hours before tiling. We did this after 14 days from the screed being poured. 
 

The reason I used Ditra mat is because a friend tiled directly onto Cemfloor and had three cracked tiles a few months later. However he didn’t fit crack inducers in any of the doorways etc 

Edited yesterday at 05:44 by Kelvin

[nod]

2 minutes ago, Antec123 said:

Thank you. Have you ever commissioned UFH with Cemfloor? Is the 7 day start time realistic?

Nearly all the sites and houses that we tile haven’t got a bio or ASHP in place at the time of tiling 

While I’m not a heating engineer the temperatures are so low that it never effects the floor coverings 

 

Weve just finished a 5 million pound house 700 m2 of floor tiles indoor swimming pool The HP is set to be commissioned in October 

and that’s on a traditional screed 

 

I commissioned the heating on both our builds {traditional screed ) Simply because I could The reality is that on most commercial or Grand designs The heating is rarely commissioned 

 

You are paying extra money Around a third for Flo Simply for convenience 

Prime tile 

[Kelvin]

Our Cemfloor supplier said the same as Nod. No need for Ditra mat, tile on it after 7 days, no need for prep just clean it, no need to commission the UFH. I chose to do all of it because we had time and I’d had enough problems up until that point 😂 

[Antec123]

Thank you guys, great info here.