tiling over floor grade chipboard - Page 3 - TilersForums.co.uk | Tile Forums

Droopy · 02-08-2008

Quote:

Originally Posted by sharpfamily

thanks to all contributors.
I can't understand a mechanism that will cause the tiles to crack.
- as regards gravity - the floor is solid and vibration proof
- temp - tiling at summer temps, so any differential thermal contraction will only occur over an individual tile, ie given that the grout's tensile strength is weaker that the tile. Thermal expansion and possibility of the tiles buckling not an issue given summer temps.
- moisture. the floor is bone dry, and any small expansion in the chipboard would only have affect across one tile width, and there should be sufficient flexibility in the bal spf to cope with that.

hence I'm going to proceed with the bal spf. I'll be sure to let you know if the tiles crack within the year.

As soon as you put any adhesive onto it, the floor will no longer be bone dry.
The water in the adhesive will make sure of that.

Save yourself any hassle and take the SPF back and change it for BAL FastFlex.
Yes the cost is greater. But this difference will be far less than ripping up and redoing, or overboarding with 18mm ply (which will be needed if you intend to use the BAL Single Part Flexible)

mark1966 · 06-08-2008

the adhesive your going to use is cement based and will only flex so much bal fast flex cost alot howtex wf21 is the same product but cost less do as the guys said prime the floor first and use the wf21 i did a floating floor years ago and to this day they havnt had a prob with it hope this helps ps the wf21 goes alot further and probally will only be about 30% more exspensive depending on what you paid for your originail adhesive mark

Brindle · 10-08-2008

I have recently tiled onto chipboard on 2 floors (against my advice) with the only adhesive I would have trusted - Bal Fastflex. Worked a treat, not very messy to use either. I also used the GT1 (?) Admix to the grout to prevent cracking in the grout. No problems. Definitely wouldn't have used a single part.

Good luck with it

**grumpygrouter** · 10-08-2008

Quote:

Originally Posted by Brindle

I have recently tiled onto chipboard on 2 floors (against my advice) with the only adhesive I would have trusted - Bal Fastflex. Worked a treat, not very messy to use either. I also used the GT1 (?) Admix to the grout to prevent cracking in the grout. No problems. Definitely wouldn't have used a single part.

Good luck with it

Ardex-flex 7001 is a single part addy designed for the very same thing and also works a treat. Cheaper too.

Brindle · 10-08-2008

Cheers Grumpy, had to get readily available stuff in my location, which was Bal (which is blinking dear

woodie · 10-08-2008

i wouldn't advise using single part flex' i agree with grumpy you're better off being safe than sorry

**pjc** · 10-08-2008

spf dont key to chipboard mate do u work in an office ? :Pete

**grumpygrouter** · 10-08-2008

Quote:

Originally Posted by pjc

spf dont key to chipboard mate do u work in an office ? :Pete

Who you askin' Pete?

**pjc** · 10-08-2008

a grumpy lol how are you mate lol

GazTech · 11-08-2008

[quote=sharpfamily;89797]i'm tiling (500*500 tiles) over floor grade chipboard using bal single part flexible. [B]do i need to apply a primer[/B], if so why, and which primer?
thanks[/quote]Hi Graham, to refer to your initial question in June this year, any use of a primer is of little or no consequence, primer has never been used to adhere tiles to chipboard, we already know that the adhesive you have chosen is unsuitable for purpose. Please let us know if they are still down .......Gaz

sharpfamily · 29-08-2008

hello gaztech,

yes the 198 tiles (500*500) are so far looking perfect after two and half months. no signs of cracking, lifting or de-bonding. The BAL SPF was very easy to use - I mixed it accurately in 5 tile batches (1.25sqm) at ratio of 5.4ltrs/20kg bag...slightly drier than bag instructions but easily workable.

I had previously experienced using the 2 part Bal on over warm board with warm-up undertile heating. This was only 3 sq m but I found it very messy & laborious to use...& clean-up.

Using the spf for the much larger 50sq m tiling was by comparison a joy. Also I didn't want to overlay with ply as this would create a step at doors with interface with carpet in other rooms.

So...so far so good....I'll let you know if the tiles are still perfect at the year end. Maybe my situation is different to others, where use of spf on chipboard hasn't been successful.
any queries welcome.
regards,
graham

**grumpygrouter** · 29-08-2008

Glad to hear that your floor is down and you are happy with it. I hope the structure is sufficiently strong for it and it lasts for you.