Tiling over wooden floor.

[Designerman]

Just found this topic via google - it's an old topic but maybe someone can help. I plan to overlay my existing wooden floor with 18mm ply screwed abd glued and then tile. The tiles are 300mm square granite and I have a flexible powder based adehesive. But I'm not sure what sort of trowel I should use for the adhesive. On another forum they were talking about - solid bed/solid bed tipped trowel/regular trowel bed but I don't know what all of these mean. I assumed I would use a trowel with notches in it that gives a comb effect similar to when I've fixed wall tiles. Can anyone help?

Thanks
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Designerman, please do not hi jack posts, see forum rule 20

 

[DIYohwhy?]

Hi designerman,

I haven't done any floor tiling myself yet. But I would imagine you'll just need a notched spreader/ trowel. The notches should be the biggest you can find due to the size of your tiles. I think usually there are three sizes, just use the biggest.

Hope that's of some use. If you're lucky, 'Moz' will also reply, he seems to know what he's talking about.

 

[gcol]

Have a look at this page and find the Rubi Stainless Steel 'U' notch trowel. That'll do ya.
http://www.tradetiler.com/acatalog/tiling_trowels.html
It's the 11th one down.
You can get a cheap plastic version from B&Q for under a fiver that'll do the job too.

 

[Designerman]

Thanks guys and sorry - didn’t realise I was hijacking a post – I thought it would save someone explaining all the stuff that had already been said (and I hadn’t read the rules). Now that I’ve got a response I’ll pick your brains a bit more just to check I’m on the right track. I’m English but live in Holland by the way. I’m going to tile the kitchen floor and it is an upstairs apartment in and old building. The floor joists are big and solid (over 200mm deep) are at 700mm centres and the span is only about 2 metres. The floor boards are about 25mm thick and also solid. So my plan is to overlay with 15mm ply glued and screwed at 200mm ctrs. I’ll lay the ply with the long edge at 90 degrees to the direction of the floor boards (so parallel with the floor joists). I’ll screw down into the floor joists as well. The tiles are 300mm square granite and 10mm thick and from what gcol suggested I’ll need a 10mm bed using a round notched trowel. Does this sound reasonable? At a push I could go for 18mm ply but with 15mm there will be virtually no level difference with the adjoining room. Do you think 15mm is enough or should I go for 18mm?

A couple of my colleagues have prepared upstairs floors for tiling and they have employed a different method. They first lay a corrugated galvanised steel sheet – here it is called swallow tail profile but in English I guess it would be dove tail profile. If you look at the sheet end on it is corrugated into a series of dove tail shapes. Over this they pour a concrete screed - which fills up the dove tail groves and gives a solid water tight finish. But it seems a bit over the top to me and I guess will increase the load on the floor and have a greater depth than ply.

Thanks.