I am new here and i have a question, and hope you can help

I am a bit confused about how to fix these marmox boards

The underfloor is 20mm boards, then 12mm ply en then 6mm marmox boards

these marmox boards will be fixed as well with screws and washers

but what kind of glue, or setting should I use to fix the marmox boards to my ply

when i bought them they said you can do it with just wood glue, or polyurethane


what is the best fixing, just set them with tile adhesive and screws?

Thanks
McLuma

cement based addy, dont dot them its got to be a continous bed

there cant be any deflection at all in the floor

12mm ply is below the reccomended thickness for overboarding, it has to be minimum of 15mm

Fitted the boards, and i am very happy had they worked for me

thanks for the pics mate it looks a good job

Hi ..

Don't forget your Alkaline resistant joint tape for strengthening the board joints , as it is a timber floor.

Hi and welcome

Originally Posted by Dave

Hi ..

Don't forget your Alkaline resistant joint tape for strengthening the board joints , as it is a timber floor.

Done,

timber floor with 18mm ply and then the marmox, its now rock solid

with underfloor heating

Don't forget to post pics of the finished job please... we love pics..

Hi Guys, apologies for jumping into this strand, but it is bang on subject for me. McLuma has done a great job, judging by the phots. I have not previously posted a question, because I find that you must have answered every question at least a dozen times. But, in a months time I am hoping to be a major player in tiling my own bathroom. The floor is currently chipboard on joists, I intended to overlay this with 12mm ply and then underfloor heating and then tile with porcelain tiles. I have been reading all the pinned threads on wet areas, when I discovered Marmox Board. I thought great, I will just use 10mm marmox board instead of the Ply, until I read McL's post and Gooner's response. Will it be the same for me Gooner, should I use an 18 mm ply, perhaps then I can use the 6mm marmox board? I also noticed that McLuma used an Addy, the Marmox site suggests that it can just be screwed to the underfloor, is it better to stick and screw? Hello to all you sage tilers, I feel like a young (53 yo), stood around the main group in the bar, listening to all the grown up conversation. Thanks for any offerings. I will be asking more daft questions over the next few weeks, I'm afraid. Steve

Steve,

Iam no pro, I, like you need a lot of information, and this forum provided it for me, but also a lot of common sense.

The marmox are perfect for tiling on, and when i bought them they told me to do fixings on every 30 cm (it says it on the instructions), to get better fixing to the floor and to get rid of every void I simply used a good tile adhesive underneath it, (call it overkill) but better done once good then have to redo it later)

It is all about movement in the floor, so the more different layers you do, the less movement there will be, (the sandwich method)

The one thing i did notice however is the amount of adhesive you use with the electric underfloor heating.

Another tip for using electric underfloor heating is, when you have layed out the netting etc, use an electric stappler to staple it to your marmox or ply, this will make life so much easier then the selfadhesive tape on the back of it.

Because you still walk over the netting it can easily move (not if you staple it down )

Originally Posted by Mcluma

Another tip for using electric underfloor heating is, when you have layed out the netting etc, use an electric stappler to staple it to your marmox or ply, this will make life so much easier then the selfadhesive tape on the back of it.

Because you still walk over the netting it can easily move (not if you staple it down )

I would not recommend the use of a stapler, you don't want any stray staples damaging your heating wires. My advice (and most pro tilers advice for that matter) is to use a hot melt glue gun. You just need a few small blobs and your UFH matt and wires will be going nowhere.

Originally Posted by Captain Slow

I would not recommend the use of a stapler, you don't want any stray staples damaging your heating wires. My advice (and most pro tilers advice for that matter) is to use a hot melt glue gun. You just need a few small blobs and your UFH matt and wires will be going nowhere.

spot on

and probe must be in condute away from metal fixings

That could be used as well,

What i was trying to say is, do not trust alone on the sticky back of the heating mat to stay put.

There is definately a need for more fixings, the use of staples can be don on the outsides of the matting, not anywhere near the wire

and always check and recheck if the mat is still functional,

Hi McLuma, thanks for your advice, stability is everything, I get your point about securing the underfloor heating and thank everyone else for their concern about the electrics.
Good advice from all.

Thanks

Steve