Is this substrate ok? - TilersForums.com

[actionjackson]

It's been a few years since I have visited.

I have to replace 2 tiles previously fitted to marmox that got damaged. When I pulled them up most of the concrete face has come off the marmox board so I'm not sure what is best. Hopefully this picture is clear to see.

 

[Qwerty]

Personally I would remove the exposed Marmox, lay new and then tile

 

[J Sid]

can't it just be primed ? Geoff

 

[On one]

For safeties sake,I would think cut the Marmox out.
What is the purpose of the Marmox and what thickness is it?

 

[actionjackson]

Thanks guys. It is 50mm marmox sitting on the concrete slab. It was added to raise the floor level and add insulation. Typically there is a power cable running in that area so I have to be careful is it a risk leaving it in place?

 

[Qwerty]

You probably could just prime & tile but my concern would be its structural integrity. Without the scrim bonded within the cement of the face of the board there is the likelihood of movement on the foam core

 

[J Sid]

I very much doubt it Geoff. Maybe if it was mosaics but not porcelain planks, if that's what are going down

 

[actionjackson]

correct, porcelain planks. For peace of mind I will replace the marmox, thanks all. Typically I had loads of off cuts and we skipped it all.

 

[actionjackson]

Ok got the tiles down and happy with the result.

Originally I was going to fill the gap between ash floor and tiles with a grout matched silicone that I hold but I'm not sure that is best. The gap is about 8mm.

Previously I had a ash threshold cover but I wasn't happy as it was a trip hazard andcin my eyes spoilt the transition to a new floor. I was hoping Top tiles did a T trim but they don't. What's best guys?

 

[Boggs]

I would use the colour match silicone.

 

[actionjackson]

My only fear with silicone is protecting the edge of the tile and because it is a cut, maybe it is sharp and could hurt someone's foot! Plus the wooden floor has a slight dip in the middle so in the middle there is a few mm lip between tile and wooden floor.

 

[Boggs]

I guess the only option is something like this then.

Laminate Flooring Door Thresholds - MDF Profiles - Flooring Direct - https://www.flooringdirect.co.uk/accessories-c8/laminate-profiles-c11/mdf-t-bar-for-laminate-flooring-p246

 

[actionjackson]

Sure it's an option but not pretty. Maybe careful silicone fill is right way to go.

Are there and metal variants of what you suggested?

 

[Boggs]

Yep.

Schluter RENO-T-A Flooring Transition T Bar Milled Aluminium 2.5m Length - https://www.northantstools.co.uk/product/schluter-reno-t-a-flooring-transition-t-bar-milled-aluminium-2-5m-length?gclid=CjwKCAjwvuzkBRAhEiwA9E3FUi_MgV_Dr6IgumyrL8zbIQWWob4Ua1rYZEIROn2gNUpbBtXrlkz7XRoCA68QAvD_BwE

 

[actionjackson]

Just need to decide what's best. Would you still continue with silicone?