1st timer- misson tile floor without cocking it up

[1st timer]

well im not a tiler but certainly no diy'er
i have my own joinery business been going 12 years so far,
when i bought my house i paid a good tiler to do my kitchen/bathroom, the time has come for another tiling job but this time i am seriously thinking about doing this one my self
im looking at tiling my living room/dining room with the view to continue into the kitchen later on once i get warrent to knock down a supporting wall,
the area im planing is 3610mm plaster to plaster with clearance under the grounds where skirting was removed for any adjusting, i plan on using 600mmx600mm porcelain tiles so thats 6 tiles wide with fingers crossed no cutting on the width of the room,
the length is 8300mm between plaster,
its going on a wood floor which i have sheeted and screwed every 150mm or less using just short of 2000 screws, long ones into the joists and shorter ones into the original boards,
i have set out a string line across the door just so i know the tiles will be ok at the threshold and have got a second line checking for square, im planning on starting from the back wall left side so i can get out the only exit, think if i can lay a row each night 6 rows souldnt be to bad, i know about starting from centre of the room by strining lines but think i should start where i have said, i will be dry laying and also chalk lining every row taking all sizes from the string along my threshold, plan on useing bar single part flexible adhesive as well, any tips or pointer would be great, although im not comitted to doing this myself yet just got it planned and thought out just in case, as you will see in the photo im stopping a good 2ft short of the wall thats going to be knocked down later so that i dont damage anything taking it down,
heres how it looks so far,

 

[jay]

how thick is the ply you have sheeted with

 

[Stewart]

How thick was the ply and did you leave any expansion gaps between the sheets.......

 

[Bolter]

Yea same, how thick is the ply? Might want to consider a decoupling membrane (like ditra matting) over the top of the ply (once we know its thick enough)

You will need to prime the ply with a proper tiling primer (not PVA)

Personally I would then stick ditra matting down using flexi adh using a 6mm trowel or smaller.

then tile straight onto the top face of the ditra. Some may say you dont need it, so you dont necessarily need to take my advice. No problem waiting for a few replies.

But, its important to get this bit right.

 

[johnryan]

i think that maybe you should ask a tiler if you know one to come round and give you some advice before you go ahead on your own. there's a lot of potential problems your looking at, and i think you need some on site technical advice really. good luck all the same.

 

[1st timer]

original floor was really flat, so sheeted with 9mm ply as per what the tiler asked me to do when i bought the house, he tiled the kitchen and bathroom floors about 8 years ago with no problems so far although i will be ripping the kitchen one up eventually,
"alot of potential problems" i really dont like problems if im going to end up with hassel i wont bother doing it, 29sqm is alot to have to get re-done not to mention the expense, hence the main reason for me thinking of doing it myself, ive got a real eye for detail so anything short of perfect wont be good enough

 

[diamondtiling]

Hi and welcome to the forum.
Are you planning on tiling directly onto the ply?

 

[1st timer]

yes that was the plan my tiler done that so thought that was ok,

 

[johnryan]

i wouldn't say it's something you couldn't do yourself, if you have the time to do it, as you seem to be willing to take your time with it. i was just thinking that you could do with some help with regards to prep. there may be too much bounce in a floor that size, and i'd have thought you'd need a decoupling mat too. also, the ply you've used is below industry standard, and you'd probably be better off with at least 18mm, and possibly extra noggins in the subfloor. if you could get a tiler to come and help you out with advice with regards to these kinds of things, then you'd have a much better chance of completing the job successfully yourself. it's ok asking for advice here, and will give you a start, but really i'd say you need someone there to give you an accurate assessment of what you need to do. also, 600x600 are quite hard to lay well, so prep is even more important here too, i think. once again, good luck and hope it all goes well for you.

 

[Stewart]

The ply is too thin as the minimum recommended is 15mm. I wouldn't recommend tiling direct to ply. If there is no deflection in the floor you void glue and screw 6mm Mo More Ply on top to give you a good surface to tile to. If you tile directly on to 9mm ply, you will have no guarantees from the adhesive, grout and tile manufacturers.

 

[diamondtiling]

To be blunt I would avoid any future advice from your 'tiler'. Some adhesive manufacturers advise that you coat the underside of the ply first before tiling and others advise the face so you need to bear that in mind. 9mm is woefully thin for this project, 18mm is advisable if you are intent on using ply, (there are better products out there)

A de-coupling membrane should definately be considered as you have not allowed for any expansion between your ply sheets. What adhesive will you be using?

 

[Bolter]

Also, be mindful of who you ask advice from. There are many people out there that will say to you "oh yea, 9mm ply is fine" but industry standards say to use almost twice that thickness. On this forum, poor advice is shot down pretty quickly, so you should get the info you need.

 

[1st timer]

ok thanks i will look into the mat stuff, the floor at the minute is 22mm t&g skinned with 9mm structual ply totalling 31mm on the joists
the joist span 3.6m on brick dwarf walls with a further dwarf wall running the length at 1.8 so the biggest span unsupported is 1.8m the floor doesnt seam to be moving but guess you cant tell 6months a year down the line,
im soaking up all this advice like thirsty sponge, im in rush to do this and even if i were to lay half a dozen tiles per day then so be it,

 

[The Legend; Phil Hobson RIP]

As above for me, 9mm ply is not good I would glue and screw a backer board, such as hardie. The quality of marine ply is not what it used to be.

Already been said but 15mm minimum ply is advised, 18mm is more common, and a little stronger. Backer boards are a good surface to tile on, but do not help much with any deflection issues.

Good luck with it.

 

[Qwerty]

Schluter Ditra all day long! Screwing down backer boards will eat up another 1000+ screws.
Did you screw all of the 2000 screws using your Dewalt? :yikes: You my man are very patient if you did.... (and probably sick of screws by now!). Autofeed screwdrivers are a mans best friend (and your back, knees, sanity etc etc :lol: )