Tiling on to chipboard flooring

[richardbell81]

Hello,

I'm a newbie here as i'm currently doing up our first house on a budget! I was wondering if you could give me some much needed advice and suggest some suitable BAL products? I'm narrowing it down to BAL as they come highly recommended! Here goes...

I'm about to tile a small bathroom floor (2.2 m2 floor space) with 300x600mm porcelain tiles (10mm thick). The house is a well built victorian mid terrace but we had to remove the old floor boards in the bathroom as some of the boards underneath the bath had rotted due to a leak around the shower end of the bath caused by the previous owners. I replaced all the floor boards with 'Waterproof treated Tongue & Groove Chipboard Flooring (18mm)' and screwed these down to the original joists as they had not been affected by the leak.

Basically, I was wondering what products you would recommend for priming the chipboard then fixing and grouting the tiles? I had planned to tile straight on to the chipboard using 'BAL Single Part Fast Flex' but was not sure what primer to use directly on the chipboard, or what grout would be most suitable?

Firstly, would you recommend using the 'BAL Single Part Fast Flex' for this job and if so what primer and grout would work best with this?

N.B. If possible, I would like to avoid over boarding the chipboard with ply as the height of the toilet soil pipe and sink is now fixed. If you would strongly advise to overboard with ply then please let me know but I could only use a 6mm thick ply at most as anything thicker would cause the toilet outlet and soil pipe to miss align (plus the sink would start to become noticeably low!)

Many thanks in advance,
Rich

 

[White Room]

Hi and welcome...you would at the least use 6mm hardie backer board fixed with single part flexible adhesive and screwed with 25mm turbo screws.....You may find if you have a tile giant near you it may save some money on the adhesive.

 

[kilty55]

hi there,i would ditch the bal idea if you are on a budget😉 over board with either 6mm aquapanel of 6mm hardi board glue and screw down and fix with spf addy

not worth the risk tiling direct to chipboard

good luck and let us know how you get on

 

[richardbell81]

ok, thanks for your reply. so not using backing board is a big no no? If i did do this, can i just use basic 6mm ply or is this not the same thing? As I said, I am a newbie but trying to learn fast!

 

[kilty55]

6mm ply is not the same as 6mm cement sheet fitted with addy and screws

as long as your chipboard is deflection free then a cement sheet should suffice

 

[richardbell81]

I already have some BAL supercover rapid flex which I was just going to not use as I didn't think it was suitable for the job. Would this be ok to ok, thanks for your replies. So... would you suggest 6mm hardibacker or a cement sheet and Is the cement sheet the same as aqua panel?

Also, I already have some of this which I was just going to not use... but do you think this would be suitable with the 6mm over board?

BAL Adhesives - Products - supercover rapid flex

 

[AliGage]

Hi Richard and welcome. Your getting some good advice already on how to prepare your floor for tiling. I would only add that i would overlay with ply before then laying the hardibacker. I don't trust chip board as a base at all. A layer of ply would give me piece of mind. I just wanted to add a few suggestions on the height issues.

"The basin looking low" comment from your first post. Can i ask are you not removing the basin to tile the floor? I would suggest you do for a number of reasons. Asthetically it's a better finish tiling first and installing on top. It's also easier rather than cutting your tiles round the sanitaryware. You could remove the basin and adjust plumbing by fitting flexi tap connectors with isolators to the hot and cold supply. This will give you more flexability in your height. If the waste doesn't line up with your pipework you could change your bottle trap to an adjustable/telescopic trap which will allow you to adjust the height to meet your exsisting pipework.
With regard to the toilet to could change your pan connector to an offset connector which will give you around 30-40mm i think. This will make up what ever you're raising the floor by and allow for your tiles and adhesive. If this isn't suitable there are other options on pan connector, maybe a flexi would work. Any plumbing supplier would be able to advise you further if you explain your issue to them.

Hope that helps on any height issues you may of had.

 

[TheTiler]

Hi Richard,

Don't forget to use a grout which is as flexible as the adhesive you have selected - BAL Single part Fastflex is probably the highest performer on the market. For this you'll need to combine it with BAL Superflex grout with Admix GT1 (hard to work with though!). Or an epoxy grout which will offer better properties (even harder to work with though unless you are practiced...).

 

[nybor62]

i would strongly advise to remove sanitary ware , much better finish imo,do not tile onto chip board it will fail eventually , over board as you have been instructed to do
bal fast flex is sound for the the job, as is bal super flex, grout, you dont need to add admix gt1to the grout as it is allready modified ,
im not far from you if you get stuck you can ring me for further assistance , good luck

 

[Andy Allen]

as rob has said don't add GT1 admix to bal super flex grout, its already modified, the GT1 is made to go with standered bal wide joint grout, mixed 1-1 with water, and it is what bal reccommend for grouting wooden floors...

 

[richardbell81]

hey fellas,

Thanks very much for all your help, i really do appreciate it.

Regarding the sink height... I completely agree about removing sanitary ware before tiling but the sink is wall hung with no pedestal. The fixing screws are already in place as I wanted to make sure the rag bolts were securely bedded in the brick (and not the tiles) so I secured these in place before tiling the wall. Basically, the sink height cannot be changed. I suppose I could fit a flexible connector to the wc pan but I have already bought a fixed straight one and wanted to avoid a flexible connector if possible. There is a bit of give on the current soil pipe but not much!

I realise it isn't ideal, and like any job I would probably do things slightly differently if I started over! I've attached a picture of where i'm at with it but I really want to try and avoid raising the height of the floor as much as possible so i'm just going to have to make the best of it.

I think I will definitely go with the BAL Fastflex adhesive and BAL superflex wide joint. If I was to overboard with a single layer of 6mm board, would you recommend cement board, hardiebacker or aquaboard for the floor? Also, do i need to prime the chipboard and /or overboard and what would I best be using for this? APD or SBR primer?

Thanks again, Rich

 

[jwatson]

sbr and yes prime the chipboard before you install the tile backing boards; with single part flexible adhesive and screws. aqua panel is what i have available to me but hardi does have a good rep too.
if bal is your adhesive choice then it is great stuff, if you can afford the prices, they are the industry leaders in this country and have good tech advice and is guaranteed for 25 years.
from what you have done already looks good from what i can see, hope you will put some photos up of the finished job.
put some real thought into removing the sink before installation, as it would benefit the overall look of your project. ask yourself the question? on completion 6 month down the line are you gonna wish you had taken it off? if not then leave it on.
hope you have got all the advice you need to tackle this project and again dont forget to put pics up of the finished job.

 

[richardbell81]

Ok, thanks very much for all your help, it really is appreciated. I appear to have 2 options...


1. Prime the chipboard, buy BAL Fastflex adhesive and BAL super flexible grout. Tile directly onto the current chipboard floor and hopefully this would do the job, although no guarantee but it would not raise the floor any higher.


OR...


2. Prime the chipbaord, overboard with a 6mm tile backing board (hardiebacker or cement board), then buy BAL Fastflex adhesive and BAL super flexible grout. Again, no guarantee, but i'm getting close. One question with this method. Would the Fastflex adhesive be suitable with the hardi/cement backing board or would a cement based adhesive such as 'bal supercover rapid flex' be more suitable? I already have a 15kg bag of the rapid flex which I was prepared to discard if the fastflex would make a better job.


Rich

 

[swanman]

Hi
And welcome to the forum

6mm Hardi board is best glued and screwed

Good Luck

 

[AliGage]

I have a third option for your Richard but it does solve issues over height and concerns over the chipboard. Does mean more work and cost however but not excessive.

Have you considered replacing the chipboard with 18mm or 25mm ply and then laying the hardi backer? It would add a bit more cost to your project. I'd estimate £80 to £100 for your materials and a days labour for a DIYer.
Honestly not trying to give you more work to do but i really would get rid of the chipboard if you can or go bigger than 6mm. The bathroom is looking great so far, i guess i'm just trying to get you to consider life expectancy as well as finish.

It's another option anyway, but looking good so far.

 

[richardbell81]

I have a third option for your Richard but it does solve issues over height and concerns over the chipboard. Does mean more work and cost however but not excessive.

Have you considered replacing the chipboard with 18mm or 25mm ply and then laying the hardi backer? It would add a bit more cost to your project. I'd estimate £80 to £100 for your materials and a days labour for a DIYer.
Honestly not trying to give you more work to do but i really would get rid of the chipboard if you can or go bigger than 6mm. The bathroom is looking great so far, i guess i'm just trying to get you to consider life expectancy as well as finish.

It's another option anyway, but looking good so far.

Thanks for your suggestion but at this stage, removing the chipboard flooring just isn't an option... it's not due to laziness or cost but the bath has been secured, plumbed and sealed in place. And add to that that I had to glue and screw the chipboard flooring down in places as it is covering up the old concrete hearth for the fire that was upstairs... so to take it up really would be a major job.

As this room is so small, and the tiled area is even smaller at just 2.2 m2 (and doesn't go across the full width of the room), I am considering just priming the chipboard flooring and fixing the tiles with BAL fast flex and grout with the superflex wide joint.

If I did do this, and i realise this is not going to a popular decision so just humour me, would I be best priming the chipboard with BAL APD, or BAL SBR? I'm not quite sure of the difference between the 2?

 

[TheTiler]

I'd give BAL a call on their technical helpline as adding GT1 with Superflex is what they told me to do. They said Superflex is not as flexible as Fastflex single part adhesive until you add further elastomericity to it in the form of GT1. Only telling you I was told..[FONT=arial, sans-serif]...[/FONT]

 

[kilty55]

add it to non flexi grout also for your grout if your going this route ,gt1 that is

 

[richardbell81]

I'd give BAL a call on their technical helpline as adding GT1 with Superflex is what they told me to do. They said Superflex is not as flexible as Fastflex single part adhesive until you add further elastomericity to it in the form of GT1. Only telling you I was told.....

ok cheers, were you tiling onto a woodchip floor or did you back it first? If you did tile straight on to a floating floor, hows it looking now?

 

[kilty55]

richard,why take the risk? the cost of a failed job does not weight up to simply over boarding and having peice of mind...

also because one floor lasts doesnt mean yours will

 

[TheTiler]

It was over-boarded with plywood - not a floating floor either as it was sat on joists. I did a very similar job for a police officer around 5 years ago. No blue sirens asking for a repair yet. I'd just pick an adhesive manufacturer, phone their technical helpline and follow their rules for prep/expansion joints etc. and mix everything in exact quantities. Then the ball is in their court if anything goes wrong.

 

[richardbell81]

sorry, yeh. I didn't mean floating floor.... I meant just a single skin chipboard on joists. Suppose i'l ring BAL technical line tomorrow and see what they advise...

 

[Muse2k8]

The bath can afford to lose 6mm in height. I would lift the basin to tile under it and for the toilet and waste you don't need to consider a flexible pan connector. I would never use them anyway as waste matter can get caught in them. However you can easily buy offset pan connectors and that is what I would recommend you do. You need a good solid substrate to tile onto and lifting your sanitary ware is easier that repairing your floor. If your basin taps are on copper pipe only then I suggest you take it out and cut down the pipes and attach a flexible tap connector hose. Just remember to seal the olive with 4-6 wraps of ptfe to keep it from leaking as with all compression fittings.

 

[richardbell81]

ok... just looked into durabase/ditra matting.... surely this is the perfect solution? Or am i missing something?

Has anyone used this before and if so, would a layer of this on the chipbaord with fasflex adhesive do the job without adding any more height??

 

[Muse2k8]

Fastflex should hold fine I would think to use ditra as ling as your floor has no bounce. What about backer board to 10mm?

 

[richardbell81]

Fastflex should hold fine I would think to use ditra as ling as your floor has no bounce. What about backer board to 10mm?

As I said previously, i'm just trying to add as little height as possible at this stage. I have considered a 6mm hardi board but from what i can see, the ditra matting seems like a good solution!

 

[richardbell81]

Ok, thanks very much for all your help, it really is appreciated. I appear to have 2 options...


1. Prime the chipboard, buy BAL Fastflex adhesive and BAL super flexible grout. Tile directly onto the current chipboard floor and hopefully this would do the job, although no guarantee but it would not raise the floor any higher.


OR...


2. Prime the chipbaord, overboard with a 6mm tile backing board (hardiebacker or cement board), then buy BAL Fastflex adhesive and BAL super flexible grout. Again, no guarantee, but i'm getting close. One question with this method. Would the Fastflex adhesive be suitable with the hardi/cement backing board or would a cement based adhesive such as 'bal supercover rapid flex' be more suitable? I already have a 15kg bag of the rapid flex which I was prepared to discard if the fastflex would make a better job.


Rich

So am i right in thinking I have a 3rd feasible option?

3. Cover the chipboard flooring with Ditra/Dura Matting which would hopefully give me the flexibility and extra layer I need.

I've looked on the BAL product guide and it says that the 'Supercover rapid flex' is ok to use with uncoupling membrane, so.... I could use this adhesive to bed the matting onto the chipboard and then use it to secure the tiles to the matting???

Has anyone used this system before and would I still need to prime the chipboard before the matting goes down?

 

[Ian]

It is an option but, bear in mind that decoupling membranes are designed to help with lateral movement not vertical, so if your floor has any deflection, a membrane will not help solve this nor will it add any strength to the installation.

 

[Peter]

Just to throw something into the mix, quite a few rubber crumb (liquid and powder 2 part) manufacturers state that their products can go straight to green chipboard providing there's no deflection. Done quite a bit of site work where was 2PF was specced straight onto chipboard and there's never been a single failure with any of the floors. Personally I'd overboard it on a private job though.

 

[Muse2k8]

Bal have a fibre based slc you can use on chipboard but you should still really be overlaying.

 

[richardbell81]

Would BAL single part fastflex do the same job? Only thing I want to make sure is that the floor is as water tight as necessary... I suppose if the tiles are fixed and grouted correctly the floor should be water proof enough?