is 6mm Delta board ok for floor?

[pc__tf]

Newbie here, so be gentle

Bathroom remodel project.

Thinking of using 6mm Delta board over the chipboard, then underfloor heating (DCM pro mat), then tile.

Is 6mm too thin for floor?

Anything thicker will create a step, which I'd love to avoid.

Any recommendations on pros and cons?

Thanks,

 

[Flintstone]

6mm is fine, stuck with cement based adhesive and screwed

 

[TheAofT]

As above and would suggest to apply self levelling compound over the underfloor heating wires as it makes safe and easy tile installation.
Good luck

 

[pc__tf]

Thanks for the replies -

I read somewhere that adhesive is not required as long as 3 rows of screws with washers are used. I even think I read it in some manufacturers' installation instructions, but can't be sure. I'm hesitant to use adhesive because next time anyone has to access the pipes underneath, they'll basically have to destroy the underfloor boards with potential damage to joists, etc. as nails/screws wouldn't be accessible. Can I do away with the adhesive, or is it an absolute must?

Thanks!!

 

[Boggs]

Instructions here for Delta Board.

I would always glue and screw them.

http://www.pcsboard.com/pcs/wp-content/uploads/2017/10/DeltaBoard-Fixing-Instructions-2017.pdf

 

[Dumbo]

Thanks for the replies -

I read somewhere that adhesive is not required as long as 3 rows of screws with washers are used. I even think I read it in some manufacturers' installation instructions, but can't be sure. I'm hesitant to use adhesive because next time anyone has to access the pipes underneath, they'll basically have to destroy the underfloor boards with potential damage to joists, etc. as nails/screws wouldn't be accessible. Can I do away with the adhesive, or is it an absolute must?

Thanks!!

It won't destroy the joists but if somebody is accessing under floor they are doing a refit anyway unless its a leak then you are probably best going through the ceiling .

 

[Waluigi]

This subject came up recently and prompted me to email a few XPS board manufacturers. I’ll have to dig out the responses. I was surprised to hear so many suggested that gluing wasn’t essential. I would always glue. Then screw if on Timber.

 

[acaciaguy]

Instructions here for Delta Board.

I would always glue and screw them.

http://www.pcsboard.com/pcs/wp-content/uploads/2017/10/DeltaBoard-Fixing-Instructions-2017.pdf

I agree and it’s always good to follow manufacturers instructions.

 

[pc__tf]

Thank you all - looks like glue it is -

but reading the PCS board instructions and I don't see them as:
Step 1: Glue and then Step 2: Screw.

Instead, it appears to me that they explain two different ways of fixing, one or the other:

Copy/paste from the PCS instructions linked above:
------
FIXING TO WOODEN FLOORS

Fixing with Adhesive: DeltaBoard can be laid using a good proprietary cement based flexible rapid set tile adhesive. Solvent based or ready mixed adhesives MUST NOT be used. Boards should be thoroughly bedded and laid in a chequer plate fashion making sure that there are no air gaps between the boards.

Fixing with Mechanical Fixings : DeltaBoard can be fixed using PCS 35mm diameter fixing washers and suitable screws at 200mm centres, i.e. 21 fixings per 1200mm x 600mm board.
-------

Toward the end of the instructions, they show a picture (Stage 3) shown as "Dry fixing without adhesive (board size 1200 x 600mm)"

Am I reading this correctly?

All this just to save 4-5mm on height.

What's the risk of going without the adhesive?

Thanks again for your help. Much appreciated.

 

[Boggs]

Warmup show the boards glued down when used with DCM Pro.

The same advice has been given from a few guys with much more experience than me and I would 100% listen to it.

I always glue and screw the boards because I don’t ever want to go back to a failed floor and the cost of a few washers and screws is nothing to redoing a floor especially with electric heating, belt and braces I think is the term.

 

[Perry]

Once the boards are down you are lucky to be 2 mm difference. So that doesn't seem like good reason imo. It would be sensible this advice rather than the manufacturers. I would use 10 mm but I like to make sure.

 

[pc__tf]

ha, funny you mention that pjc - I was thinking exactly that: being a non-expert, who do I listen to? the manufacturer of the board, or the advise here?

In any case, I will go with adhesive because if everybody agrees, it must be for a reason.

But I do have another question: building regs require that you draw the location on the chipboard of the pipes underneath. If I cover everything with adhesive, then whatever is drawn will be hidden. And I will say, in this project, those drawings have been instrumental. That's another reason why I wonder if I can live without the adhesive.

A big thank you to all those contributing. This forum is a lifesaver.

 

[acaciaguy]

To my knowledge they don’t. But take a picture and measurements. I do it on all my jobs and helps I think.

 

[Perry]

If you listen manufacturers some are good. A lot just want to sell you something, they don't always care if it fails.

 

[acaciaguy]

If you listen manufacturers some are good. A lot just want to sell you something, they don't always care if it fails.

From experience who are good and who are bad