Speccing replacement joists

[leedjc]

Morning all

I am replacing the first floor joists in the front of our house. I could do with some clarification with regard to the span tables.

It is an old house, and want exposed joists downstairs (yes I know it'll be noisier, but it's the look we want). Will be using 600 centres. Open span is 3.5m.

The thing I'm a bit confused about is the load. The table I've been looking at has specs for three dead load ratings. Which do I need for this job?

Thanks
Lee

 

[tony1851]

If you're not putting a ceiling in, it will probably be the column with dead load not more than 0.25k/m2.

but beware; it's a structural alteration and needs a building regs approval. You may have to put a ceiling in for sound- and fire resistance requirements, and possibly surface-spread-of-flame regs.

 

[leedjc]

Thanks, I've got a building control application in at present, just waiting to hear back. Hmm, fire spread. Didn't think of that. Might well scupper the open joist plan!