Advice on joining floors to level please!

[1111]

Hey all - My first question!

I am helping a mate lay ceramic tiles to a floor in a refurb - he levelled the floor with concrete about 4 months ago (although it does slope about 3mm).

The issue i have is that he wants the floor levelled to the same height as the next room - there is a concrete step of about 2" at its highest point - Am I right in thinking that we can lay exterior grade ply to help level the existing floor and join us upto the step maybe finishing off with a threashold reducer? It will be ajoining onto a slate floor which has already been laid. He mentioned Sterling board (is that the same as OSB? It looks like it) as it was cheaper but didnt want to say yes in case its not good enough. Or should I just lay on the concreate and try and ease the step off with a small ramp down somehow.

And finally would the ply or OSB need some kind of primer before the adhesive is laid?

Thanks

[grumpygrouter]

Sounds like you will be better laying down small joists and putting in a new floor that is level with the bit you are joining to. If you did this you could get a really good surface to tile onto.

Sterling board is not suitable for tiling onto.

Grumpy

[1111]

Thanks grumpy - Would you do that anyway because of the 3 mm the floor is out (regardless of the step) or can that be levelled with extra adhesive?

I assume we would use the exterior grade ply then if we laid a new floor.

Anthony

[grumpygrouter]

3mm is not a significant variation. BS states that 3mm under a 2m level is fine. You can use exterior grade ply, either WBP or Marine. You may also want to do some research on using backerboard of some sort instead of ply if you are going to build a new floor. Never done it myself but if the situation arose, I certainly would investigate this before making a decision.

Grumpy

[Dave]

3mm you can lose in the adhesive bed no probs..........if you want to bring the floor up 2 inches then i would screed the floor...plying the floor out is just adding a potential movement problem to a concrete floor.....

[1111]

Originally Posted by grumpygrouter

3mm is not a significant variation. BS states that 3mm under a 2m level is fine. You can use exterior grade ply, either WBP or Marine. You may also want to do some research on using backerboard of some sort instead of ply if you are going to build a new floor. Never done it myself but if the situation arose, I certainly would investigate this before making a decision.

Grumpy

Thanks Grumpy - There i go again running before I can walk! I'll think I'll look into another alternatives before testing my joinery skills on my unsuspecting mate!

Anthony
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Cheers dave, I think thats the route I should start to head down - I just read on another Post about Thick bed adhesive or SLC with chippings - what do you guys think any personal preference?

Anthony
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Originally Posted by Dave

3mm you can lose in the adhesive bed no probs..........if you want to bring the floor up 2 inches then i would screed the floor...plying the floor out is just adding a potential movement problem to a concrete floor.....

Sorry for the double post - still getting used to this quote button!

Cheers dave, I think thats the route I should start to head down - I just read on another Post about Thick bed adhesive or SLC with chippings - what do you guys think any personal preference?

Anthony

[Dave]

50mm is alot to do with self leveller and chippings and get it flat...screeding would be easier to handle....good luck and let us know how you get on.........

[1111]

Originally Posted by Dave

50mm is alot to do with self leveller and chippings and get it flat...screeding would be easier to handle....good luck and let us know how you get on.........

Many thanks to you both - I'll let you what we go ahead with and maybe post a pic on completion of my efforts for some constructive critisism!

........then again maybe I'd get more than I bargined for!

Cheers

Anthony