Hardiebacker only screwed to chipboard. No adhesive

[Mr Tiler]

Yes, I would agree with your statement. We call the adhesive layer a gap filling bed of adhesive, and it can be flexible or non-flexible. The purpose isn't to make the board stick, it's to fill the gaps or voids between the subfloor and the backer.

brill mate that's exactly how I think of it. cheers

 

[Rookery]

Yes, I would agree with your statement. We call the adhesive layer a gap filling bed of adhesive, and it can be flexible or non-flexible. The purpose isn't to make the board stick, it's to fill the gaps or voids between the subfloor and the backer.

I've always used this method to fix Hardie but have sometimes wondered if, when boarding a perfectly flat chipboard floor, why use adhesive as there are no gaps to fill?

 

[Mr Tiler]

I've always used this method to fix Hardie but have sometimes wondered if, when boarding a perfectly flat chipboard floor, why use adhesive as there are no gaps to fill?

in my opinion if a floor is perfectly flat just use a smaller trowel size at least as it surely helps to glue and screw rather than just screw

 

[Herbis]

Yes, I would agree with your statement. We call the adhesive layer a gap filling bed of adhesive, and it can be flexible or non-flexible. The purpose isn't to make the board stick, it's to fill the gaps or voids between the subfloor and the backer.

Sorry to revive a (very) old thread, but I can't seem to find an answer for my question anywhere online - including by contacting James Hardie Support - so hoping you can help?

I have a P5 chipboard floor and 6mm hardie backer to go over it. There are seemingly no options to apply tile adhesive on to the P5 - no manufacturer recommends their product is used in this way, even with primers. How, therefore, is it possible to apply a bed of tile adhesive when going over P5 chipboard? Is it sufficient to use a grab adhesive instead?

Thanks!