Laying Backer/insulation boards

[Dan]

Of course, there's that too.

 

[JCT]

Thanks guys. Ripping up the chipboard and plying isn't really an option. Will take too long and just add cost. Insulation boards have already been purchased and floor is ready for starting tomorrow. I will install the boards using rapid set.

Here's something I've always wondered about. It's recommended to use 1 part flexi sticking the boards down on the chipboard but this would be unsuitable if tiling straight onto the chipboard. Why is ok to use spf on the boards?

 

[Old Mod]

Thanks guys. Ripping up the chipboard and plying isn't really an option. Will take too long and just add cost. Insulation boards have already been purchased and floor is ready for starting tomorrow. I will install the boards using rapid set.

Here's something I've always wondered about. It's recommended to use 1 part flexi sticking the boards down on the chipboard but this would be unsuitable if tiling straight onto the chipboard. Why is ok to use spf on the boards?

Because the idea of the adhesive is not for holding it down, it's for taking the unevenness out of the substrate you're putting the boards on to, the mechanical fixings (screws) hold the board down.

 

[JCT]

Because the idea of the adhesive is not for holding it down, it's for taking the unevenness out of the substrate you're putting the boards on to, the mechanical fixings (screws) hold the board down.

What if the subfloor is already flat?

 

[Old Mod]

You asked me why it was used, that's the reason.
To ensure the board has full contact with the floor.
If u wish to use only screws then that is your choice, as long as it fits within the manufacturers instructions.

 

[Dan]

There we go. 🙂