Plywood subfloor - continuous flooring throughout bungalow

[benjy_b]

With part of our renovations I'm replacing the terrible chipboard subfloor in our bungalow with T&G WBP spruce plywood.

The area we are working on has been gutted and taken back to an empty shell.

I'm making provisions for additional subfloor rigidity and strength at the moment.

Joists are:

75x220x4600
75x220x3300

400/450 centres

I've fitted 47x175 solid noggins.

Our intention is to fit the same flooring (Karndean) throughout the:

Master bedroom
Hallway
Dining room
Kitchen
Living room
Study

Tile the en-suite (wet room) and bathroom.

Carpet the spare bedroom.

My question is, shall I go with 18mm or 22mm ply?

The chipboard currently fitted is 18mm.

Our aim is to have no stepped transitions.

My lack of knowledge at the moment is in the area of tiled flooring in the en-suite.

Anything I should watch out for/be aware of?

 

[Cgas]

Have you fitted all them noggins ? What for exactly ?! Christ do you run a timber yard ?!
Also would probably cut the section by the door out as it looks unsupported and waiting for someone to snap it off.

 

[benjy_b]

Yeah, all the C16 timber is what I've fitted.

You've got noggins @ 400 centres between two joists for structural support of a studded wall (you can see the void for the wall plate in the plaster at the end).

There are also two runs of noggins at 1/3 intervals across the span to stop twisting and add rigidity.

It's only £35 worth of timber and £10 worth of screws?!

Good spot with the previous chipboard near the door. I got lazy and wanted to change task, it was taking ages to trim it back to the joist with my multi tool.

It's only me doing the work, so I know it's there.