Bathroom floor

[mutley]

Hi guys,

firstly apologies in advance as I know that "plying out" has been done to death many times before.

Got my bathroom floor to tile, only 5 m2. Now I know that I should ply it out first, at least 12 mm, however on lifting the old laminate the floor has already been covered in hard-board all nailed down, i'd say about 2-3 mm thick, the original floor is tounge and groove floor boards, with in my opinion very little movement.

As I'm doing it myself if it goes wrong later i've only got myself to blame, what would you do ?

Rip it up and lay 12 mm ply, leave the hard board and cover with 9mm ply or maybe 6 mm hardi-backer ? If it makes a difference to the replies, regardless of the outcome the toilet and sink pedastel will be removed for the tiling.

Thanks in advance

[devonmark]

Either rip it up or go over it...I would go with no more ply or hardi purely for the reduction in step....should really be 18mm ply but 12mm will be fine..Mark.

[Sir Ramic]

Ply or Hardibacker i would get rid of the hardboard.

[Raja]

rip it up and go over with 12mm ply

rip it up.........you want the least amount of substrates.....
if the subfloor (t&G) is solid 12mm (min) ply screwed 6" centres.

good luck!

[mutley]

Thanks for the speedy replies,

was hoping to save myself the hassle of lifting the board, not now though.
It all depends on the different floor levels which way I go now. For those that've used Hardi or No more ply do you thinks that 6 mm is ok on Tongue and groove and do I have to leave an expansion gap between the boards if I go down this road ??

Promise no more questions tonight.. Cheers

if the t&g is solid you can use
1. dietra mat
2.hardibacker (glued & screwed)
3. no more ply (glued & screwed)

no more ply reccomend you use thier "special" glue......however any
polyeyrothaine glue will do!

[grumpygrouter]

Personally I wouldn't be happy tiling onto hardboard. If the floor is rigid as you say the options are pretty much as Protilers suggested. Hardiebacker 6mm is specially designed for floors and is more dense in it's construction than the 10mm Hardie board. Also means you can use normal flexy addy instead of timber specific stuff. I have never used No More Ply.

Ditra is specifically designed to "decouple" the tiles from the main substrate in lateral stress environments, it is not designed to make timber floors rigid so just bear that in mind if you choose that route.

Check out Schluter.co.uk for more info on this.

Grumpy

[Fekin]

Rip up the thin hard board.

Screw down any floorboards that seem slightly loose or have a bit of play in them along the joists.

Cover the floorboards with a bed of flexible adhesive.

Lay down 6mm hardi backerboards and screw every 300mm

Remember to leave a slight gap around the room for expansion

As above and the floors going to be as solid as it's ever going to get, and as low as your going to get it, unless you just use fastslex on the floorboards, and remember to lay the boards staggered so you don't have 4 corners all meeting in one point.

[GazTech]

I'd rip it all up to expose T&G, secure as Fekin says, then 6mm backer and 2 part flexible with flexible grout additive....Gaz


[B]BAL Fastflex Powder & Liquid [/B]
[IMG]http://www.bal-adhesives.co.uk/bal/bal_products/images/fastflex.jpg[/IMG] A two part, rapid-setting, sulphate-resistant, water-resistant and frost-resistant floor tile adhesive and isolating, anti-fracture underlay, suitable for use in interior and exterior locations. Suitable for fixing ceramic floor and porcelain tiles and mosaics (including fully vitrified), dark natural stone and slate. Suitable for use on tile backer boards, glazed tiles, concrete bases, cement:sand screeds, tongue & groove floorboarding, plywood overlay, floating plywood/chipboard floors, ceramic/quarry tile/terrazzo/hard natural stone bases, vinyl tiles/sheet, mastic asphalt, steel, glass reinforced polyester (GRP), steel and galvanised steel. Conforms to BS EN 12004, Type C, Class 1F.
[B]BAL Wide Joint Grout[/B]
[IMG]http://www.bal-adhesives.co.uk/bal/bal_products/images/wide_joint_grout.jpg[/IMG]
A water-resistant, frost-resistant cement-based powder grout designed for grouting ceramic floor tiles, mosaics, quarries etc. Also suitable for use on walls. Not recommended for soft glazed wall tiles, or tiles with metal decor or lustre. Suitable for use in interior and exterior locations in both wet and dry conditions. Suitable for swimming pools. Conforms to BS EN 13888, Type C, Class G1.

NOTE: The physical properties of BAL WIDE JOINT GROUT can be enhanced by the addition of BAL ADMIX GT1. The polymer admixture imparts flexibility, increases adhesion and reduces the water permeability thus widening the application possibilities of the grout, with a classification of BS EN 13888, Type C, Class G2.

[B]BAL Admix GT1[/B]
[IMG]http://www.bal-adhesives.co.uk/bal/bal_products/images/admix_gt.jpg[/IMG]
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[mutley]

To everyone who replied, thanks for the advice, cheers.

Fekin, thanks for the "step by step", much appreciated.

[project damager]

Hi Guys

Sorry to drag this one on again, I must have read it 5 times...

I have a similar project, En-suite 3.4sq mtrs, Bathroom 4.8 sq mtrs - T & G base...

I thought that I was going to put 12mm ply down but if there is an option to use 6mm hardi, I think I would take it?

Do you simply lay the hardi on the T&G and then screw or do you have to glue the hardi to the T&G and then screw...

2 more...

1. I lay hardi in strips, like brick work (laying down - not on top of each other ;-) )

2. What size of expansion gap all around? I am tiling floor and walls and want to use a tile skirt as well...

Thanks to everyone for any help

Brian - The Project Damager