Advice needed on laying porcelain tiles

[Time's Ran Out]

i dont give advice to those who dont listen

I agree!

 

[Tile Shop]

I have time so I will give advise, more for the reason that everyone can say "they told you so" if you ignore them and it all goes posterior over mammaries .

Tiling onto timber, the spacing required for screwing is maximum of 300mm in BOTH directions, not 125 one way and 400 the other. Thats daft!

So unless you are going to lift the floor up and stick noggins in, you're on course for an emotional battering. If you don't, its a ticking time-bomb! If you do, you also need to find an adhesive manufacturer that will guarantee their products on chipboard.... Or if you do end up with the right spacing, Ditra Matting fitted with AF200, then tile on that with and S1 cement based adhesive. But that won't eliminate deflection.

Do yourself a favour and just overlay it with NMP or Hardie like everyone says. It'll cost you less than having to do it twice!

 

[Boggs]

There are some chipboard manufacturers that don’t recommend direct tiling to their boards, regardless of what adhesive manufacturer says.

 

[Boggs]

Hi All, I will be laying 9m2 of 600x300 rectified polished porcelain tiles in my bathroom. It will be over green chipboard and I know all the advice is against this but I have tiled over chipboard before and not had a problem. It is new chipboard, well screwed down at 5” centres with no bounce in the floor.

Question 1. Should I prime the floor with something like Mapei Primer G?

I plan to use Mapei Keraquick with Latex Plus (recommended by Mapei for laying on chipboard)

Question 2. What size and type of trowel. I have read lots on the subject and I am more confused than ever. I would think a 10-12mm square notched trowel on this size of tile, giving a 5-6mm bed. But there are many recommendations for round notched trowels on floor tiles as it gives better total coverage. The problem is it also says that whereas a square notched trowel will result in a bed half the depth of the notch, with a round notch trowel, the bed would only be a third of the depth of the notch, so 3mm for a 10mm notch. Surely this isn’t enough.

Question 3. Tile spacers. As these are rectified tiles, I plan on using a 2mm spacer, is this OK? I am planning to use Mapei Ultracolour Plus which has a minimum grout line of 2mm.

If you have already tiled over chipboard in the past with no problems then surely just do exactly as you have previously.

 

[Dumbo]

I agree!

What was that you were saying

 

[Time's Ran Out]

What was that you were saying

I agree!

 

[Sam68MvAgusta]

I'd be more worried that you've packered underneath the joists, unless you've tapered the packers the full length of the joists you're going to get flexing near those packers and inevitably the chipboard will breakdown it's structural integrity, tiles cracking, grout breaking down and leaks, good luck with all that!

 

[Dumbo]

I'd be more worried that you've packered underneath the joists, unless you've tapered the packers the full length of the joists you're going to get flexing near those packers and inevitably the chipboard will breakdown it's structural integrity, tiles cracking, grout breaking down and leaks, good luck with all that!

Agree should be proper furrings ( if that is how you spell it )