Best way to level my Floor

[eggtastico]

Wonder if someone can give me advice.

I have 2 rooms that have been knocked into one.

I had to replace the Joists on one side as the beams had been eaten away - either rot or woodworm.

Now Originally I was going to seperate the 2 rooms like they used to be..
But as it goes, I have decided not to & now have 2x Rooms with about a 7mm Difference in height

I bought a Job lot of Arditex - 2x batches.
http://www.ardex.co.uk/arditex_na.asp
So would like to use that.

Also, I plan to lay reclaimed Parquet from front door to backdoor.
Know, the kitchen/diner area is a step lower, but I would like the lay to be continueous from the front door to the step, going through my passage & living area. - this area is the same height as the lower 1/2 of the room - but currently has laminate on top - which makes it the same height as the higher room!

So whats the best to do?
Rip up the laminate & screed the whole area
rip up area & use 3mm hardboard on the area & then screed everything level & then lay 6mm plywood ontop?

Instructions say :-

Prior to levelling wooden floors, screw
down and firmly fix all loose boards.
Where timber floors are sufficiently rigid
but are uneven or worn, or where there
is differential movement between floor
boards, the technique is to pre-level the
timber with ARDITEX NA prior to screw
fixing minimum 6mm thick WBP plywood
to receive resilient flooring or at least
15mm thick to receive ceramic tiles or
natural stone to provide a sound and
stable base for the new flooring.
In all cases sub-floor ventilation must
be adequate to prevent deterioration
and moisture movement.

 

[mattysupra]

plywood not hardboard! Also i always do it the other way around so your left with compound as the finished surface. It is only ardex that say do it this way. All other manufacturers say do it my way round. But every one else uses water based compound not latex, you should not be gluing to latex compound. Do it as they tell you if you want half a leg to stand on if it goes wrong. I would not use ardex tho myself. Brilliant products but not my favourite.

 

[eggtastico]

Thanks for the quick response matty.

So I shouldnt finish with a latex finish if im going to be glueing the blocks,
Guess that means I'm stuck to putting plywood ontop? They are old finger type parquet blocks.

should I use the ardex on the whole area or use hardboard to take the lower floor up 3mm & then do the whole floor?

I can take some photos if it helps to explain & show the height differences.

Thanks again.

 

[mattysupra]

first of all. HARDBOARD NO NO NO, Plywood yes yes yes! Dont use hardboard. If you can get the correct thickness between the floors using plywood and no compound then this is always the best method. I recommend that you use compounds over wooden subfloors only when you want to lose a slope or if you have dips etc and you want the floor flat without having to raise floor height by an inch. If your floor can be made flat by using plywood then use plywood only. You can get plywood as thin as 3.4mm. There is no need to get a level floor but only smooth and flat. But if you want a level floor then the only real way of getting a level floor is by using compounds. ( almost impossible with latex tho )

 

[eggtastico]

Ok, Thanks.

I have to have the floor level for the parquet blocks. At the moment one room is about 7mm or so higher than the other.

I think I will lay plywood to bring one floor level with the other. Then screed so its all tied together & then more plywood ontop

Raising the floor an extra inch isnt to much of a problem.
I am planning on replacing the doors & skirting anyway & the whole floor is going to be treated as one big continueous/flowing area.

Thanks for the advice. Just waiting for the plasterer to finish the walls before I can start on the flooring

 

[mattysupra]

what you mean or should i say all you should be aiming for is smooth/flat sub floor. Not a level one! But if you want a level one as well then yes use compounds. But you could also end up raising one end 2" or so and nothing the other end! You will never be able to tell if the floor is not level and the only level sub floors i have ever seen are ones which i have done. There really is no need.
What i would do if i was you -
1- If your floor boards are flat ( no cupping/crowning ) go ahead with the plywood. If not sand them flat. Buy a belt sander from b&q for about 40 quid and get some 40 grit paper. Or hire a proper floor sander. ( but really no need! ( there big, heavy, hard to use and your not trying to get a perfect finish ) The plywood will loose any minor differences for you.

2- when the floorboards are flat, plywood the lower side with 6mm plywood. This should leave the two floors almost level.

3- Get some feather finish compound and ramp out any minor height differences. +or - 1-2mm

4- next over board the whole floor with 6mm plywood. You should now have a perfect floor.

Instead of sanding the floor boards down you could get thicker plywood and screw down. But this will cost more money and raise the floor height when there is no need for it.

You also do realise that you cant put the compound straight on top of the floorboards dont you? It has to go onto plywood. Which means you will end up using more plywood aswell if not having the compound as the finished sub floor.

 

[eggtastico]

Yep, that explains everything.. Not level, just flat is what im looking for.

Its Chipboard flooring & brand new - the floorboards fell to dust when I pulled them up to replace the joists.

Think thats the plan then.

Plywood the uneven side, compound on top & then plywood the whole area

Cheers for the advice.

 

[mattysupra]

compound only if you need it to take out any LITTLE dips or to ramp between floors. And also you can not use compound over chipboard unless you install plywood first!