Mezzanine floor question

[GJUK]

Hello,

I've got a large industrial unit type domestic garage which is about 20mx9x5m and I'd like to erect a steel I beam framed mezzanine in the garage.

Are there building regulations I need to be aware of, Its not for walking on, access will be only via a ladder and I intend to not tie the structure to the building at all, other than to the concrete base itself.

The I have bought is a 2nd hand Mezzanine is 5mx4mx2.5m.

Thanks,

 

[freddiemercurystwin]

Why does it need access if no one is going to walk on it?

 

[GJUK]

Why does it need access if no one is going to walk on it?

To get up to the level to store items on the mezzanine? Maybe?

 

[freddiemercurystwin]

So you or someone else could walk on it if you/they wanted to?

 

[oldbutnotdead]

There are regs to do with structural stability, strength for intended use and means of escape (you won't be living up there presumably but you will be up there moving and storing and retrieving the Stuff that you want to store).

Things to consider;
All the load will be transferred to the floor probably by 6 legs. What is the total mass of your mezz and what sort of weight do you plan putting up there. Can the floor take that load? (Assume the structure weighs 1 ton and you're going to store 2 tons of Stuff. With 6 legs, each leg would be exerting a force of 5000 newtons on whatever the contact area of the leg foot is. A fairly chunky load but your 100mm concrete floor on properly compacted hardcore should take it. If you have any doubts about the thickness of the floor then drill through it (somewhere inconspicuous) and see how thick it is. Worst case you might have to cut some of it out, dig deeper and refill with concrete- irritating rather than a showstopper.

Structural stability- how much crossbracing is there in the mezz? Will it/does it sway at all- if it does then you'd be best tieing it to the walls. No great horizontal load will be imposed but it will prevent the vertical loads from exceeding the footprint of the mezz and causing it to topple

Means of escape. Have a think about being up there of an evening going through your collection of Jackie or whatever when there's a bang, the lights go out and you see a flicker of flame below you. You really should consider some emergency lighting and a proper access staircase with handrail (could be at ladder type steepness but the handrail and solid fix is important). And a handrail round the perimeter of the thing so you don't stumble 2.5m to your doom.

As far as formalities go, adding a mezzanine would put you outside the 'standard' outbuildings detailed in the Approved Documents. You can either crack on and hope for the best (considering the above) OR have a chat with your local friendly Building Control dept in your local council and see what they reckon (on a hypothetical basis to start with of course). The tricky bit will be the (presumed) lack of documentation with your pre-enjoyed structure- do you know, for instance, whether it has been involved in a fire or been exposed to ionising radiation? Without some provenance, you might end up having to get a structural engineer to prove that the design is sound and (if your BCO is really on the case) he/she might insist on metallurgical analysis of a few samples. Fire-damaged steel might look fine (with a fresh coat of paint) but it may fail at loads well below those which clean steel will support. Radiation isn't a big structural issue with steel (unlike titanium) but might not do you any good.