Subfloor for engineered floorboards

[Reggie82]

Hi,
I’m planning to fit engineered plank floorboards in a living room. It’s an old Victorian house with suspended floorboards and a large cellar space underneath. I’ve been advised to lift the existing floorboards to the joists. Then lay caberboard with ply on top. The engineered floor will be nailed to the ply. Does this sound accurate?
I’m concerned the floor will sit much higher than the existing original floor in the hall (not in a position to afford to replace that floor too just yet).
Thanks in advance!

 

[dazlight]

Could go 6mm sp101 plywood and glue it down.

 

[Notch7]

Hi,
I’m planning to fit engineered plank floorboards in a living room. It’s an old Victorian house with suspended floorboards and a large cellar space underneath. I’ve been advised to lift the existing floorboards to the joists. Then lay caberboard with ply on top. The engineered floor will be nailed to the ply. Does this sound accurate?
I’m concerned the floor will sit much higher than the existing original floor in the hall (not in a position to afford to replace that floor too just yet).
Thanks in advance!

Is it 21mm structural engineered or 14mm overlay engineered.

21mm (20mm - 22mm) can be fixed directly to the joists

If you use 14mm you need to put down a rigid subfloor like caberboard first.

If it’s above a cellar space it needs insulating and a vapour barrier put down

 

[Reggie82]

thanks for the reply. It’s 20mm engineered boards.
I assumed it would just need a ply subfloor. The caberboard seems excessive but I don’t know the reason why I would need to use both?