New subfloor for engineered wood floor?

[Wuzzie]

Hello all,

I am looking at laying new wood flooring in the upstairs rooms of a Victorian townhouse. The existing floorboards are in a terrible state after decades of abuse, central heating, etc. They have shrunk, are splitting badly and have patchy woodworm, so I don't think they can really be salvaged. The joists that I've had exposed (admittedly only a small sample) appear to be in fine condition, though (with the exception of a few creative gouges where central heating and electrics have been installed), and on about 300mm centres.

Budget dictates that I'd be using engineered flooring rather than solid boards; I'd like to lay the new flooring in the same direction as the existing boards. Looking at the state of the original boards, my gut feeling tells me to get rid of the old boards and lay a plywood or chipboard subfloor as a loadbearing element to lay the flooring over,

My questions:

- Is this the right thing to do (replacing the original boards)?
- If so, what material/thickness should I use for the subfloor?
- Are there any better alternatives I haven't thought of?

Thanks,

Richard

 

[DAZB]

I would first of all check out the woodworm because if it is still active you might have some joists to replace as well as your flooring. If it is an old infestation and unless the floor is beyond use then you really don't need to remove the floor.
You could lay the new floor over the top but you will need to either remove skirtings and architraves and refix over the new floor or use beading around the room to cover the gaps.Your doors will need to be cut down too.
Or you could remove the floor and replace with 18mm Tongue & Groove Chipboard (assuming your old floorboards were 18mm) and then lay your new floor over that.