Raising solid floor by an inch

[Lobster]

I have a walk-in cupboard, in which the floor is an inch lower than the room it opens onto (because it used to open onto another room, and I knocked a doorway through into another room instead). Both the upper and lower levels are solid floors (ie concrete), in good nick, and level, and there's an inch-deep step down into the cupboard. The floor area of the cupboard is approx 1.4 sq metres (he says, mixing his units as usual).

What's the best/easiest way to tackle raising the level of the cupboard floor? Seems too much for a levelling compound job? Should I use concrete or cement instead? Advice on what mixture I should use would be much appreciated.

Thanks David

[sPoNiX]

Personally, I'd use a layer of concrete and finish off with levelling compound.

[[news]]

personally, I'm lazy so I'd use a bit of 19mm flooring grade chipboard with a 6mm ply 'finish' on top, neatly giving the inch the OP is after

[Lobster]

Well I'm certainly lazy too; that's not a bad idea... although the 'inch' was only eyeballed; I'll have to experiment with some scrap boards and see what I can come with.

Thanks David

[Michael Mcneil]

I've done that in a pub refurb. They used shuttering ply and it looked dreadful. Then someone came along with self leveling compound and put it all right. I was impressed.

[Lobster]

I ended up going down the above route; laid the concrete on Thursday and now need to put down a few mm of self-levelling stuff. How long do I need to leave the concrete until it's considered dry enough to lay the self-leveller though, so it will adhere? The concrete's 'gone off' OK, but I realise it takes ages to dry completely.

Thanks David