Putting down hardiebacker board

[Hulloo]

Good news, you should be OK, one tip, cut all your boards first and dry lay, leave a 5mm gap around the perimeter, also stagger the boards ( brick bond) leave 2mm/3mm gap between boards, take up one board at a time, glue and screw each board so the adhesive is still wet. Once you have glued and screwed all the boards. Tape all the joints with an alkali resistant tape, depending on the make of your boards, this will prevent cracking on the joints

Must i use flexi adhesive to secure the boards down seeing as the screws will be holding them in place. Reason i'm asking is i have the 1 back of flexi adhesive enough to cover the area of floor tiles require but have quite i bit of the non flexi wall/floor adhesive leftover......Just me being a cheapskate

 

[Mike]

you must use flexi adhesive as the wood can expand and contract and the flexi adhesive will allow for that. don't risk the floor failing for the sake of a tenner!

 

[The Legend; Phil Hobson RIP]

As Mike, don't skimp now

 

[Bathfix Bob]

Makes you wonder though how many people (trades included) use dri wall adhesive to glue the hardie backer boards down, it sure is cheaper than tile adhesive at *** a bag.

 

[Mike]

Makes you wonder though how many people (trades included) use dri wall adhesive to glue the hardie backer boards down, it sure is cheaper than tile adhesive at £16 a bag.

surely you can get decent adhesive for less than that bob?

 

[Bathfix Bob]

Annoyingly no, its gone up a quid aswell lately. Ultra from local tile shop.

 

[grumpygrouter]

Must i use flexi adhesive to secure the boards down seeing as the screws will be holding them in place. Reason i'm asking is i have the 1 back of flexi adhesive enough to cover the area of floor tiles require but have quite i bit of the non flexi wall/floor adhesive leftover......Just me being a cheapskate

I am going to go slightly out on a limb here and I am waiting for the "barrage" from the more experienced guys who post here.....

......the adhesive is used with hardie board as a void filler NOT as an adhesive to "stick" the boards down, that is what the screws are for. As such you may be fine to use not flexy adhesive. Indeed the hardie installation literature just states "adhesive" not flexy adhesive when fixing the boards, even on the timber floor fixing instructions.

 

[Rich]

Im pretty sure that No More Ply state a single part flexible adhesive (although I may be wrong). I would like to be safe and go with a tile adhesive.

 

[grumpygrouter]

Im pretty sure that No More Ply state a single part flexible adhesive (although I may be wrong). I would like to be safe and go with a tile adhesive.

I thought No More Ply preferred there own expanding polyurathane adhesive Rich? I have never used the stuff so I don't know for sure though?

 

[jay]

The Home Of No More Ply

here ya go

 

[jay]

I am going to go slightly out on a limb here and I am waiting for the "barrage" from the more experienced guys who post here.....

......the adhesive is used with hardie board as a void filler NOT as an adhesive to "stick" the boards down, that is what the screws are for. As such you may be fine to use not flexy adhesive. Indeed the hardie installation literature just states "adhesive" not flexy adhesive when fixing the boards, even on the timber floor fixing instructions.

You are correct Grummpy the adh is just to fill hollows in the floorboards so the cement sheet is fully supported the screws hold it in place

 

[Rich]

Yeah, of course they do, my mistake. Sorry. Maybe Im thinking of aqua panel? Or was it No More Ply on screed?

 

[Rich]

Iv just had a read though and they state "a rapid setting adhesive" for fixing their boards down on to a screed.

You might be on to something there grumps, I wonder what Hardie or No More Ply would say about it?

 

[grumpygrouter]

Iv just had a read though and they state "a rapid setting adhesive" for fixing their boards down on to a screed.

You might be on to something there grumps, I wonder what Hardie or No More Ply would say about it?

About what mate?

 

[Rich]

About what mate?

I have just always assumed that the boards should be laid onto a bed of single part flexi adhesive but now you come to mention it I dont know where I got that from. If they just say "adhesive" or "rapid setting adhesive" I wonder if they are being vague for a reason or if they have a adhesive that they would recommend if you asked them?

 

[jay]

Hardie sheet not recommended for concrete floors (look under installation) James Hardie® ceramic tile underlay sheets - CSP Cement Sheet Products

 

[grumpygrouter]

Hardie just specify an adhesive bed laid with a 6mm trowel and it is just to fill voids. They also state that deflection should be less than Length/360 otherwise the tiles may crack because of deflection. It looks like No More Ply is a slightly different type of cement board to Hardie but ihave never seen it so I don't know. I remember No More Ply when first intorduced tried to say it was a straight replacement for 15mm ply and would strengthen floors as well but their marketing info now seems not to include that, just that it is a tile backerboard!! They make a great play on their Polyuerethane adhesive though....and I don't think it is cheap!

 

[Rich]

Hardie sheet not recommended for concrete floors (look under installation) James Hardie® ceramic tile underlay sheets - CSP Cement Sheet Products

I was on about No More Ply Jay.

Thats strange tho, I wonder why one says it can be used on concrete and the other doesnt? They are the same product.

 

[jay]

Iv just had a read though and they state "a rapid setting adhesive" for fixing their boards down on to a screed.

You might be on to something there grumps, I wonder what Hardie or No More Ply would say about it?

Must of read it wrong sorry

 

[Rich]

No mate, thats my bad for not being clear. I meant that I read through the NMP website.

Unfortunately my hands type faster than my brain thinks... And spells :lol:

 

[The Legend; Phil Hobson RIP]

I mostly use Hardie board, and to be belt and braces, I use Mapei Keraqick and latex plus to glue and screw. I screw at 150mm centres and lay into the adhesive while it is still wet, thats why I dry lay the boards first, do all the cutting, then glue and screw one board at a time. Works for me, but each to their own.

 

[jay]

Food for thought //
the reason for not fixing (sticking) tiles directly to timber floors//////

is !