How to fix a fibre sheet to engineered floor?

[geoffr]

We wish to install a fireplace on a Hearth in our living area. The Hearth will be tiled on a fibre cement sheet that will be fixed to the existing engineered oak flooring. I don't want to damage the flooring in case we should ever remove the hearth. The fibre cement sheet will be tiled.

What is the ideal fix to attach the fibre cement to the floor in this case? I am guessing a silicon or a glue that won't stain?

Thanks

Geoff

[JacobZ]

Hi @geoffr,

Unfortunately, I am not aware of a fibre cement sheeting product that can be installed without any mechanical fasteners like you are proposing, and I can't say I am confident that you would find a fibre cement sheeting manufacturer who would recommend a method of installing fibre cement sheeting without mechanical fasteners.

You'll note that a fibre cement sheeting product like Hardie™ Ceramic Tile Underlay, as per the Installation Guide requires a large number of mechanical fasteners. 

Unfortunately, I don't know if there would be a way that you could install a tile backing without causing damage to your floor.

Your best bet might be to ask your fireplace installer for their recommendation. They may have come across this situation before and have a solution they can recommend.

Sorry, I couldn't be more help.

Allow me to tag @Nailbag and @Dave-1 to see if they have any ideas.

Jacob

[Dave-1]

Afternoon @geoffr 

Now thats an interesting question, when I moved in to my place and pulled up teh carpet I found a very rough section of floor that had been covered with bricks of some kind, the floor had also dipped with the weight of whatever was there. I presume a potbelly stove and associated brickwork for the floor an wall. 

This was what I uncovered, pretty much a non finished floor and gritty.

It sanded out and came up nice tho.

Maybe you dont need to attach it to the floor, If its heavy enough it wont shift? Or use a fixing agent in the corners only?

The main thing I want to bring to attention is if your floor has been ok'd to take the weight oevr a long term. This is the result of an old standard for garages and having a lot of weight above plus I suspect a water leak Levelling a timber floor.

Just something to factor in is all.

Dave

[geoffr]

Thanks Jacob, that's helpful. The oak was laid on a concrete slab, and glued down. Considering your reply, a few screws should be sufficient to hold the cement sheet in place and the holes could be easily filled if ever required. As it's also in the corner the weight of the tiles and stove will make it difficult to move at any rate. 

Let me know if you see an issue with that, but it seems to me it will be secure and create no hazard.

Regards,

Geoff

[geoffr]

Thanks Dave, we're on a concrete slab so dipping shouldn't be a problem. Yes, I think a few screws will be sufficient, as the hearth and stove will be heavy above it.

Regards,

Geoff

[JacobZ]

Hi @geoffr,

Unfortunately, I can only recommend the methods that the product manufacturers do.

Ultimately, you can use the materials how you wish, but if you are installing them outside of the manufacturer's recommendations, you would not be covered in the event of a failure.

If you were going ahead with this method, I would still suggest you run it by the fireplace installer, so they don't come out and tell you they won't install the fireplace over the hearth that you've built.

Good luck!

Jacob

[Nailbag]

Hi @geoffr 

The only way to prevent damage to the existing floor is not to actually fix the hearth to it in any permeant fashion. Personally I think the weight alone of the tiles, adhesive and the cement sheeting along will have be enough depending on its size. But your suggestion of using a silicone adhesive like a SIKA product would guarantee it doesn't move but also provide a temp/perm solution that wouldn't damage the your timber floor.

Nailbag