another chipboard query

[doug boardley]

firm I'm subbying to have decided to do away with ply overlay on bathroom floors, at my suggestion, but they've caught me cold, I've always tiled onto overlayed ply and not sure of best method to tile onto chipboard (22mm,well screwed, with a moisture resistant coat on top).Looking for some advice so I don't look a fool!
cheers
Doug

 

[oldgit]

if its the waxed top type chip you will be advised to steer clear,but i would find out what the coating is,if its just waterproof green chipboard then i would use any 2pt,topps are now doing 2pt palace rebranded topps for £16 this cover about 3.5 mts

 

[AllurePTS]

I cant help wondering why you suggested it doug ??? ........if they are doing their upstairs floors in 22mm ....tell them to double dwang the joists and do the bathroom in 18mm marine ply INSTEAD of chipboard (if they are all getting tiled that is) - problem solved.

 

[doug boardley]

it's not the moisture resistant green board, it's grey resinous looking topping,seen it hundreds of times, just can't think what it's called!

 

[Perry]

firm I'm subbying to have decided to do away with ply overlay on bathroom floors, at my suggestion, but they've caught me cold, I've always tiled onto overlayed ply and not sure of best method to tile onto chipboard (22mm,well screwed, with a moisture resistant coat on top).Looking for some advice so I don't look a fool!
cheers
Doug

one of the best ways is to overlay it with 12mm ply : pete

 

[doug boardley]

I cant help wondering why you suggested it doug ??? ........if they are doing their upstairs floors in 22mm ....tell them to double dwang the joists and do the bathroom in 18mm marine ply INSTEAD of chipboard (if they are all getting tiled that is) - problem solved.

It's a massive new build mate,floors were down and studs up months before I suggested it

 

[doug boardley]

one of the best ways is to overlay it with 12mm ply : pete

that's what we've always done Pete, but because I've (stupidly?) suggested there might be an alternative,site agent is keen to try one to get over step issues

 

[DHTiling]

You can't tile on it doug.......use a thin ply for grip and 2 part sticky....

 

[doug boardley]

thanks all for replies, will tell site agent (sheepishly haha!):74:

 

[Perry]

that's what we've always done Pete, but because I've (stupidly?) suggested there might be an alternative,site agent is keen to try one to get over step issues

I quite often tile on chipboard with just decoupling matting but it is 40mm thick with steel joists at 300 centers that would be an alternative for him. :lol: I always use a reducing strip the same width as the door only has to slope 10mm to the hight of the carpet : pete

 

[Grace'sDad]

Dave, did you manage to find out what this grey (or sometimes green) coating is called? Ta!

 

[BDS]

Yeah i`d like to know too cos i`m on with a job with the same flooring by the sounds of it

 

[DHTiling]

Sorry lads..i forgot.....busy man you know......leave it with me...........( again)..

 

[mz30]

On a building site i will tend to want any chipboard floor to be plied out,however on my own house i tiled straight onto the chipboard ,5 years down the line there is still no problem with the floor.

Now 2 years ago i tiled my mum's bathroom floor and used marine ply and screwed every 6" and it has now cracked along a couple of grout joints,i used the same adhesive/grout on both jobs(mapei) and yet the job with the higher spec has failed,what does that tell you?

By the way my mums bathroom has a lot less traffic than mine does,and the only thing i can put it down to is the fact that there are two lots of surfaces moving in hers, compared to the one in mine,can't say about the site work as you never really go back into those house's.

 

[DHTiling]

Right here we go........

EUROSPAN® HDX Laminated Chipboards (Hexham, UK)
These load bearing boards can also be offered with a number of value added finishes:
HDX Protect: For use in areas where the surface needs to be highly resistant to
abrasion. HDX Protect is coated on one side with grey melamine kraft paper and
has anti-slip properties.

http://www.egger.com/pdf/Eurospan_en.pdf

scroll down to see the grey coated one............

 

[grumpygrouter]

I have never seen these boards before. Does this coating alleviate some of the "splintering" problems that can be associated with chipboard and hence is a good surface to tile onto or does the coating make life more difficult?

 

[BDS]

Cheers dave its the weyroc thats on this job i`m on for defo,

 

[DHTiling]

I have never seen these boards before. Does this coating alleviate some of the "splintering" problems that can be associated with chipboard and hence is a good surface to tile onto or does the coating make life more difficult?

The coating is only sort of laminated to the surface russ..so no ....

 

[BDS]

Grumpy i`ve had to take the floor up to add and redo some pipe work and it still splinters not quite as bad tho

 

[BDS]

Question/s for ya guys,this bathroom wich has 4.5m2 of this weyroc chipboard flooring,when i`d lifted to do all new pipework etc etc etc i`d noticed the joists,now as i`ve seen tons and tons of joists before,but wasn`t expecting these I joists cos never worked on new builds oldest bathroom/house i`ve ripped out was approx 8yrs old and this is only 2 years old,so is there min/max c/c joist widths and can you still put same fixings in to secure when i`ve put them back down (hardie backer going on top)only reason i`m asking is cos there was only 5 3" ring nails holding the full floor down and it was tiled on previously as well

 

[grumpygrouter]

Sounds like a good opportunity to put in some noggins to add strength while the floor is up. Boards should be screwed down at no more than 300mm centres. There is definately a minimum size of joist but I am not sure what the exact size should be.

 

[BDS]

cheers grumps thats what i usually do BUT with these (i joists)not been the norm for me thought i`d ask,put noggins in BUT the c/c joist widths are 6oomm so thought that was a bit wide but like i said these are new to me and not the norm and didn`t/dont know if there was any special or different requirements ie fixings etc etc etc,,,,

 

[Perry]

So the laminate has to be removed ? ete

 

[AllurePTS]

Are these "I joists" made with a form of OSB in the centre ???

 

[BDS]

Yes mate it is,

 

[AllurePTS]

Ok then - they are TJI's ....a highly engineered timber product that is actually STRONGER than a solid wood joist, they have far less deflection than standard joists and also designed to significantly reduce sound resonance, hence they are often called "Silent floor" or "quiet floor system" ....because of the way they are made - they can cope with much bigger spans than conventional solid joists and are often used to avoid the need for steel I beams where it's not desireable, and also just for quality / sound reduction . They will be on 600 centres (rather than the usual 400) because that's all they need to be in this particular build. You can place a nogging on the top part of the I section (the softwood header) only if you need to (to join a board say) ....do not join through the centre OSB section though ....you will NOT need to do any addittional strengthening work - this stuff is mega engineered in the same way that roof trusses are, it's fitted with steel hangers to an engineered wallplate, it's all pre calculated for each individual building and will take way more weight than it will ever realistically encounter !!!

It's a funny thing ...looks like cheap crap when you first see it, but it's far from it !!!!

So .....minimum noggins, use the correct length screws (you dont want them too long and splitting through the OSB) keep your screw lines well centred and if you need to go through them with pipes etc - make sure you only go through the CENTRE of the OSB section

 

[BDS]

Cheers allure your a legend ,it sure does look like cheap crap,who ever installed original pipe work and wiring have just,well what it looks like to me is taken a hammer and just smashed holes in for pipes/wiring instead of cutting nice neat one`s (lazy :furious3::furious3 so basically just use the same methods as the old timber joists,

 

[DHTiling]

Be careful.....that stuff deflects like hell when installed in long lengths......

 

[BDS]

Cheers dave ,cos i`ve had to cut flooring up it should be ok (i think:lol cos of it not being in long lenghs anymore,and cos of cutting its given it a sort of expasion joint (well sort of in theory) :lol:

 

[doug boardley]

hopefully there should be a pic or two in album I've stuck on my profile, is it the stuff you meant Dave