Raising floor height

[Piers]

I want to raise the height of a floor on the first floor, to match the height of an adjoining room.

The obvious and easy way to do this would be to run 45x70 C24 perpendicular to the existing joists (with the 45mm being height), as

45mm is exactly the height I want to increase by and I have these timbers already. In addition, I'm nervous about increasing the height of the existing joists as they are narrow (but not undersized for the span) and there is no bracing between them. Running the C24 perpendicular to the existing joists gives the added benefit of cross bracing the existing joists.

The existing joists are 50mmx200mm, 400mm spacing, 2.4m span.

Does this sound like a sound approach?

Piers

[Roger Mills]

Sounds ok. 45x70 doesn't have much bending stiffness when laid flat, as opposed to stood up - but they're supported by the existing joists every

400mm, so will probably be ok.

Others might disagree!

[Tim Watts]

On Monday 28 October 2013 15:46 Roger Mills wrote in uk.d-i-y:

Sounds absolutely fine to me.

[Geoff Pearson]

What kind of floor is going down? Orientation to new timber?

[Piers]

18mm solid wood, perpendicular to new timber.

[Geoff Pearson]

Therefore parallel to the original? T&G? Just intrigued.

[Piers]

Yup, parallel to original joists. Not t&g. I hate t&g - I've had to lift too many t&g floors to lay it myself. These'll just be square edged boards.

[Bob Minchin]

What are you doing at the top of the stairs? One unequal riser could give problems. Possibly best to build up the tread height over a few stairs progressively.

[Piers]

Stairs aren't relevant here as this room is nowhere near the stairs. There's already lots of different and weird and wacky floor heights in this house!

[Piers]

Thanks chaps.