Floor joists

[KevB]

Hi everyone
This is my first post on this forum,seems a great place to find info.
My question is i am putting a new floor in my attic , i live in a typical terrace house in the UK and want to know does anyone know the size of the floor joists i should use.
there is a suporting wall in the centre and i am planning to use joist hangers , is there anything else that i need to know.
Thanks in advance for your help
Kev

[Eli]

I think pretty much everyone here will say to consult an engineer, for legal purposes, or at the very least span tables.

Really depends on what you're going to use this reclaimed space for. How much active or static load it'll have on it. If you're running on a treadmill up there it's a lot different from storing some boxes of Christmas decorations.

Most likely you'll end up halving the spacing and doubling the frequency of what's already there.

But you'll also need to give us more info to work with.

[pawnhead]

How wide is the span?
The code is different to the one here in Oz, but if you're doing it on the sly then there's span tables here (http://www.fordtimbers.com.au/dpr_span_tables.htm) that would give you the sizes required.