Render over particleboard flooring?

I've been asked to turn a spare bedroom into a bathroom. The flooring is yellowtongue and the owner wants a door -less shower. This will mean some rendering to create a slope before tiling.
Can anyone tell me if concrete rendering over yellowtongue would be possible or successful. I'd imagine lots of Bondcrete in the render would help.
Should the floor be waterproofed before rendering?
Should I take out the floor in the shower area and box up and lay a concrete pad (there's about 300mm clearance under the floor)
Any ideas??

take out the floor in the shower area and replace it with 19mm comporessed cement sheet.

It is done a lot in project homes (2nd storey) where the P/B flooring is waterproofed then a screed bed followed by tiles installed. Just make sure u follow the instructions for the waterroofing and install sufficent angles to door ways and have enough fall to the shower waste and the floor waste.

The screed bed is just sand and cement mixed dry, consulant your local floor tiler for the idea ratios.

The echnidna's suggestion is the best way to start, but it is also the most expensive option.

It is common practice to lay directly over particle board. First you must waterproof before the cement based bed is placed. Within the cementbased bed you add reinforcement in the form of a stainless steel mesh (not concrete reo).

The cement bed is a must because you need to create a fall to the waste pipe.

Now to be really thorough, you can waterproof the cement based bed as well. This method works and is within the Australian standards.

The waterproofing can be done by yourself if you follow the manufacturers instructions which must comply with the Aust standards but waterproofers aren't that expensive and they give long guarantees for their work, some even lifetime. Remember, water can do wonderful things to framing timbers.

But if you get your falls wrong, like out the door, then all the waterproofing in the world wont help you. So a good tiler will do the cement bed properly. Just a tip on the cement bed, dont try to make the cement based bed runny like mortar, make it dry and pat it down.

Hope this helps

Good luck

It used to be quite common to see galv bird or chook wire used as reo rather than expensive stainless, or is that no longer kosha?

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Originally Posted by johnc

It used to be quite common to see galv bird or chook wire used as reo rather than expensive stainless, or is that no longer kosha?

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Spot on mate. My brother in law (tiler) who contracts for AV Jennings has all his material supplied. They didn't supply anything before and he used to put in the galvanised chook wire. They now supply the stainless mesh. I'm not sure that you cant use the galvanised stuff. I haven't come across a problem with it in the past but as there are always updates to building practices and codes/standards, so the only way to be certain is to check the standard.

By the way Tarty, dont you have to be a licenced builder to do that sort of work? Or is this a love job for a mate, or the owner you speak of, your partner etc.

Thanks blokes - that's about what I suspected and yes, Boban it is a love job - an in-kind job for a helpful relative!

Quote:

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Originally Posted by Tarty

I've been asked to turn a spare bedroom into a bathroom. The flooring is yellowtongue and the owner wants a door -less shower. This will mean some rendering to create a slope before tiling.
Can anyone tell me if concrete rendering over yellowtongue would be possible or successful. I'd imagine lots of Bondcrete in the render would help.
Should the floor be waterproofed before rendering?
Should I take out the floor in the shower area and box up and lay a concrete pad (there's about 300mm clearance under the floor)
Any ideas??

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Hi, Tarty, our son is a tiler and our new place has particle yellow tongue flooring. We tiled 2 bathrooms and a toilet area by fibre glassing the area and painting a membrane over that to seal it. I'm not 100% sure what the bed mix was but I think it was 2 to 1, pretty dry. That was done over 3 years ago and we have had no hassels whatever. He put a small tube like dam near the doorway if I remember rightly Anyway I don't think you need to rip up the exisiting floor as tiles are laid over P/board it all the time now.

I looked it up in the standard AS 3958.1 - Guide to Installation of ceramic tiles.

"welded wire mesh... mesh size of 50 x 50mm.. not less than 2.5mm diameter. 'chicken wire... should not be used in place of reinforcement' ... should be galvanised ..."

I took out the boring stuff, can't cut and paste the pdf :mad:

Hope this helps
Pulse

by the way the 50 by 50 is hard to get, James hardie suggest 75 by 75 in the manual for hardipanel flooring