Replacing floorboards - building regulations?

[skvsn]

I'm going to replace floorboards (chipboard) on the 1st floor as they are not level and were cut in pieces to route central heating pipes (this was done many year ago and look ugly with many unsupported joins, cracks etc). Now space between joists is empty. According to current building regulations do I need to put any sound/thermal insulation in the void? What material is better to use?

I will need to raise the level of some joists as they are about 2-3 cm below the others. Is it OK to screw some timber (lets say 30x50mm) along the joists to achieve required level and screw floorboards to them?

I'm going to use standard T&G chipboard flooring (22x600x2400) and laminated flooring on top. What other layers do I need to put between them? Is it just underlay (something like this for example - http://www.wickes.co.uk/invt/620801)? As I understand on 1st floor I don't need any DPM etc - am I right?

Thanks for your help

 

[JohnD]

chipboard is at its best on a bonfire.

If you're ripping up the old stuff, why don't you replace with ply?

 

[skvsn]

If you're ripping up the old stuff, why don't you replace with ply?

chipboard has T&G - will be easier to lay down as I don't need to put any noggings to support joints. 600x2400 panels are easier to work with than 1200x2400 for plywood (even not sure that I will be able to bring such a big sheet upstairs)

 

[JohnD]

you can get 600x2400 T&G flooring ply.

unnogged chip cracks.

 

[skvsn]

you can get 600x2400 T&G flooring ply

OK, this sounds interesting. What kind of ply thickness do I need if the joists spacing is 400mm?

 

[skvsn]

but what about void insulation - is it required?

 

[tony1851]

but what about void insulation - is it required?

If it was a groun floor, then yes, it would be notifiable and you would need to apply thermal insulation.
But not for the first floor.