Floor Joists - Office Filing Loads Re-generate an old or tired space and give it a fresh breath of life. Click here for answers, information and tips

[senses]

Morning All

Don't know if anyone will be able to point me in the right direction with a problem I can't get my head around.

I'm looking at a roof conversion - where the roof space will be used for office filing storage only. The building is a garage 6m x 6m

There are currently 100 x 50mm ceiling joists at 450mm centres

Ideally I'd like to lay the new floor joists between the existing ceiling joists to take the loads.

The span of the roof is 5550mm.

I'm looking at TRADA span tables and for the life of me I can't work out how I would be able to store office filing.

British Standards say to go with 5.0kN/m2 for office filing

I'm not going to use the whole roof space as I will have to make allowances for the eaves - ideally I just want to get archive boxes up there. I want to allow room for moving them about etc.

There will also be a access hatch within the ceiling - 1m x 1.m

Can anyone explain to me how I work out that the floor joists can take the loads from the filing?

I've been looking at this for hours and I'm just going round in circles...

Thank you :)

[stoneyboy]

senses,
If you were to fit 75x220 SC4 grade joists at 400mm centres your floor would then be able to take a load of 0.25kN/mxm.
You haven't got a chance of meeting your requirement of 5kN/mxm unless you fit a number of universal beams to support the existing joists.
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