Floor thickness mismatch

[morqthana]

I've got places in my house where some of the original 1950s floorboards are either no more, or need to be no more, with currently a mix of different thickness newer replacements and sheet materials.

I want to get it all sorted before new carpeting is laid - I may find that (eg these people https://www.hoylanddismantling.co.uk/product-155/imperial-sized-floor-repair-boards.php ) can supply boards I can drop in and end up with a level surface, or I could use new boards with packing on the joists, e.g. DPC.

Question is, if I'm having carpet and good quality underlay, just how close in thickness do new and existing sections need to be to each other? Is it a case of more than a Rizla thick discontinuity will eventually show through, or <1mm won't matter, etc?

 

[Wayners]

Replace with the correct thickness board.
Find a reclamation yard and buy some that match or get local timber supplier to source some new ones.
They can run new floorboards through a planer thicknesser if your boards are an odd size easily.

 

[ree]

OP,
Why not post pics of the floor - it may be that a simple & cheaper way of dealing with your issues is possible?