levelling a step in the middle of a floor

[Udhi]

Hi all,
30 foot x 12 foot lounge. Suspended wood floor in very nice condition. I am planning to install solid brushed oak, oiled floor.

Problem is that there is a blinking big 20-25mm drop in the floor at the point where there had been a wall partitioning the lounge into the original front and back sitting rooms (the rear floor is lower). The base of the concrete wall is still visible, but smoothed off into a gradient over about 30cm between the two pine floors.

Any advise on how to solve this problem?

PLEASE dont tell me to pull up the flooring and add packing strips and all that stuff! I cant make it and my new neighbor is a bit of an ass, she will complain about the sound.

The school of El Kabong advises simply applying a 20mm WBP ply over the lower portion to bring it level or near as level (I am sure the difference is odd and there will be at least 10mm outstanding over the 300mm drop). Is this Ok?

Udhi
DIY School of El-Kabong

 

[mac391]

Can't picture this Udhi

Is it a 20/25mm drop (as at the begininning of your post) or a 300mm drop (as at the end of your post)

Or is it 20mm ply and 10mm outstanding ??

A picture would be handy!!

Or an explanation not born out of El - Kabong

 

[Udhi]

I am sorry mate.

Basically the lounge has been created by knocking down the separating wall between two reception rooms. There is a 20-25mm difference in height between the floors in each room - the rear one is lower.

So there is a difference, like a step down over the area where the wall existed. I suppose the wall was about 10 or 12 (300mm) inches thick. Some numpty (not this one, another one!) had tried to make this STEP into a slope by putting concrete over that 300mm step left by the old wall. Obviously this will not do as I want a solid 30 foot expanse of wood, no steps....

I hope this makes sense. I am about 240 miles away from this job, at this time!!

 

[mac391]

I would pack the floor until level but you don't want to do that !! So... You could lay 20mm WBP and if the levels all round are 10mm out say from one end to the other your new floor should sit on it fine if it's a gentle gradient. If it's 10mm out over just couple of meters then it will be noticable and put stress on the new floor.

If you want perfection then you could lay f-ball 700 flex. It's a screed designed specifically to go over ply and can be laid between 2mm and 10mm thick. you can lay it 10mm at one end down to 2mm at the other !!

hope this helps.

 

[Udhi]

That certainly helps, Thank You.

I was thinking of installing WBP on the lower floor to bring it up. But was worried how close the tolerances needed to be between the two floors.

So the floor is going to be happy as far as we do not exceed a deviation of 10mm or so.