adhesive under hardi backer on chip board

[merit]

hi all
ive always thought its better to glue and screw hardi backer boards down when over laying chip board, but it seems hardi recommend only screwing, why is this , does cement based adhesive react with the chip board ? or is there another reason im unaware of
thanks

[whitebeam]

No idea, I glue and screw chipboard..

[Stewart]

The adhesive is used more as a void filler rather than for sticking it to the substrate..... but I glue and screw mine.


Created on iPhone.....

[kilty55]

i use knauf boards as oppose to hardi and glue and screw also..never an issue

[ROBSON MCGREGOR]

I got told today when enquiring about wedi boards that if its in a wet room you must not screw through the boards, you must only fix with adhesive.
Is this right?

[Dave]

I got told today when enquiring about wedi boards that if its in a wet room you must not screw through the boards, you must only fix with adhesive.
Is this right?

Unless you tank over the fixings..

[Dave]

hi all
ive always thought its better to glue and screw hardi backer boards down when over laying chip board, but it seems hardi recommend only screwing, why is this , does cement based adhesive react with the chip board ? or is there another reason im unaware of
thanks

Using adhesive will prevent any small voids, this can happen is the screws do not pull down fully tight.. and on floor boards it is to fill in concaving/convexing boards..

[ROBSON MCGREGOR]

Unless you tank over the fixings..

I said about tanking over the screws but they couldnt tell me yes or no.
I told them that they must be mechanically fixed but they told me that you dont have to, the adhesive will be fine.

[Dave]

I said about tanking over the screws but they couldnt tell me yes or no.
I told them that they must be mechanically fixed but they told me that you dont have to, the adhesive will be fine.

It will be fine... ask them why you tank over wall fixing's with wedi then ffs.. how silly they are..

[STEVO]

just noticed the posts there, do you throw screws in as you are laying the boards while addy still wet, or do you wait till dry?

[Bri]

Screw whilst addy is still wet, it pulls it tight to the substrate an gives 100% coverage.


Sent from iPhone using tapatalk

[STEVO]

cheers Bri.

[doug boardley]

if i remember correctly, UK and US advice differs on the way to fix hardie. Any idea which country's version you've heard merit?

[merit]

its from the uk , i can understand the difference in floor boards and chipboard, and the gap filling the adhesive would achieve, i always glue and screw ,but hardi said do not addy on chipboard,its come from a third party so i didnt have chance to ask the reasons,you would think belt and braces in all cases

[Sir Ramic]

Backerboard Installation | James Hardie United Kingdom