plaster nest to tile

[devonlad]

ok, just studded and battened all walls. new suspended floor with 22mm p5 (was gonna be glued wood floor but now decided tile. plan is to overlay with 6mm hardi on the floor but not sure what to do on walls.
1. green plasterboard
2. 12mm hardi

wanna tile shower area to ceiling and about 600mm above bath.
with the other plastered areas should i plaster first then tile or tile then plaster to the tile.

opinions..

 

[Karis]

Don’t use chipboard for the floor, its total crap & unsuitable as a tile base even when over boarded IMO. you will also have adhesion problems with the green MR stuff. Why go to all the expense of over boarding P5 with Hardi, use WBP ply straight onto the joists, 18-22mm depending on your floor joist size/width/span. Screw down every 150mm & provide noggins on unsupported edges, although you can get away without them next to the walls if there is no loading. Acrylic prime/seal the back side & edges (but not the tile base) before laying.

For walls in dry areas you can use MR (green) plasterboard but use a decent waterproof tile backer board in wet areas unless you’re going to tank. Hardi is fine but being only 12mm thick it won’t lie flush with adjacent 12.5mm plasterboard. 12.5mm Aquapanel works well & is what I use. Mark your tile line & get your plasterer to skim just beyond the line, feathering into the PB. MR plasterboard board must be primed before skimming but don't generally plaster where your going to tile. Cement boards need additional prep before skimming but it's not normally advisable.

Use quality trade tiling products of the correct type for your tile base & the type/size/weight of your tiles, cheap DIY products are mostly rubbish. Follow adhesive manufacturer’s instructions for priming, if necessary.

 

[devonlad]

thanks for that. changing chipboard aint an option now. so have to overboard with something. 22mm with 300 centers. span is 1.8 and using 150x50 and nogged. its rock solid. so question is 6mm hardi on the floor or ply. will look into the aquapanel.

 

[Karis]

Hardi boards must be glued as well as screwed to the floor. As I said, if you have green (MR) P5, then you will have adhesion problems. Lifted this from the Caberfloor P5 website;

Ceramic tiling
• Tiling onto Caberfloor should be undertaken only in joisted or fixed floor constructions.
• Noggins should be used between the joists at 300 mm centres and the surface provided for tiling should be 15 mm exterior grade plywood screwed to joists and noggins at 300 mm centres. Existing boards can therefore be overlaid with 15 mm exterior grade plywood to provide the necessary rigidity for a tiled surface.
• Length of fixings should be 2.5 times overall board thickness. A tile adhesive is the recommended bond material - cement/ sand mortars are not recommended.

If the Caber isn't laid yet, I would seriously consider going to WBP ply & save yourself the hassle.

 

[devonlad]

caber is down and taking up would be a ball ache as stud work and battens are in place. although adhesion of hardi to p5 might be a bit of an issue would pleny of screws in hardi help? or a thinner ply screwed onto p5. i have no worries about ridgitity of floor really, only adhesion of tiles.

also as to the wall issue only 2 walls are holding tile. shower booth and bath are on same wall. dimensions are 3000x1800 for room so not huge. i could hardi the entire walls being tiled so step would not be a problem or would you still recomend aquapanel. what kinda price is the panel?

cheers

 

[Karis]

caber is down and taking up would be a ball ache as stud work and battens are in place. although adhesion of hardi to p5 might be a bit of an issue would pleny of screws in hardi help?

Over boarding floors with 6mm Hardi relies on an adhesive bond as well as screws to stiffen everything up in order to provide a solid tile base, hence the requirement for screws & adhesive. Additional screws in 6mm board will make a difference but I would go to Hardi 500 (12mm) or use 12.5mm WBP.

or a thinner ply screwed onto p5. i have no worries about ridgitity of floor really, only adhesion of tiles.

I would not recommend/use ply thinner than 12.5. The BS, Tile Association & most adhesive manufacturers stipulate 15mm minimum for over boarding but 12.5mm is sufficient on most floors. Personally, I will never overboard chip as I would have to pick up the pieces & pay the bill if it goes wrong. I can't afford & won’t risk tile failure but as it's your project, your choice.

also as to the wall issue only 2 walls are holding tile. shower booth and bath are on same wall. dimensions are 3000x1800 for room so not huge. i could hardi the entire walls being tiled so step would not be a problem or would you still recomend aquapanel. what kinda price is the panel?

You can go for backer board over the whole wall then but do use Hardi 500 (12mm) for studding out not 250 (6mm). Aquapanel is slightly thicker at 12.5mm, cheaper & just as good IMO & is why I use it. If you want to plaster part of the wall, you will need additional prep over cement boards to get good adhesion & avoid failure.

 

[devonlad]

so what is the problem with overboarding? not trying to start anything here just wondering really.

what is the price difference between hardi and aquapanel? was gonna use 12mm on walls anyway.

 

[Karis]

so what is the problem with overboarding? not trying to start anything here just wondering really.

Not sure about your question really & I never said there was a problem with over boarding! IMO it’s never my ideal situation but it depends on what you have & what you intend to overboard with. What you’re aiming for is a rigid tile base that will remain stable so if that’s what you think you have then fine.

what is the price difference between hardi and aquapanel? was gonna use 12mm on walls anyway.

It very much depends on what you can get it for which probably won’t relate to what I get it for! You need search around & check out the prices for yourself but my guess is that it AQP will still be cheaper.

 

[devonlad]

what i kinda meant was the problem with overboarding p5. and i meant in general where people have a problem ith it as i see it slated a lot on forums "crapboard"
yes, if i had know i was tiling originally i would have used ply

got a trade accounts at jewsons/interline and buildbase so will play them off as to price. roofer by trade and got a good turn over with them so should get a reasonable rate.

how dose moisture resistant plasterboard compare/differ to aquaboard?

 

[Karis]

what i kinda meant was the problem with overboarding p5. and i meant in general where people have a problem ith it as i see it slated a lot on forums "crapboard"

That’s a perfectly good & accurate description for even a general floor board base.

how dose moisture resistant plasterboard compare/differ to aquaboard?

Just to be clear; Aquaboard (Lafage) is only a moisture resistant plasterboard & the same as British Gypsum MR PB; Aquapanel is a totally different, cement board product. If you meant Aquapanel compared to MR PB/Lafarge Aquaboard then there is absolutely no comparison when it comes to use in wet areas.

 

[devonlad]

so am i right in thinking my best option is to aquapanel the walls i am tiling and ok to aquaboard the skimmed/painted walls.

shame osb aint any good for it.. always keep a pallet of that in my store for my flat roofs.

think i will have to go with a well screwed 12mm ply on the p5 then.
can you recommend a good adhesive or does it depend on chosen tile.

 

[Karis]

so am i right in thinking my best option is to aquapanel the walls i am tiling and ok to aquaboard the skimmed/painted walls.

Aquaboard/MRPB is perfectly OK for tiling in dry areas but you need to prime before skimming. Use Aquapanel (or other waterproof tile backer board) for tiling wet areas unless you’re tanking.

shame osb aint any good for it.. always keep a pallet of that in my store for my flat roofs.

Shed roofs, site security & shuttering are about the only thing it’s good for but not much else.

can you recommend a good adhesive or does it depend on chosen tile.

There are a few good trade products but as to what type depends on how good/quick you are at tiling & how long you need to/can wait before grouting; but it’s BAL every time for me.

 

[JohnD]

plaster nest to tile

nest?

 

[devonlad]

next

 

[devonlad]

ok, took down studs, taken up p5 and cut ply ready for laying. what a ****ing ball ache..

what primer do i use on back and edges?

do i do anything to the tile surface?

what adhesive grout do you recommend for porceline? its a beige tile and not sure what colour grout to go for