Building a Mezzanine

[Crazy Dazz]

I have been toying with this idea for some time. I have a very large (brick) garage, with very high ceilings.
I've had a view different ideas, including a "proper" mezzanine, but the ceiling isn't THAT high.
So finally, the idea is basically just storage.

So what is the best method of construction & materials?
I'm a decent carpenter, and have built some impressive structures in the past, but I'm not sure timber will cut it.
It will need to span 6.8m, although there IS a big I-beam in the middle that I could possibly hang-off for support.

I have looked at pallet racking, however getting the correct dimensions is tough.

[Danny]

If it's spanning 6.8m and there is an I beam in the middle then whatever members you use will be spanning 3.4m only.

For storage only you won't need hugely rated members unless you're storing really heavy stuff or wanting to live up there, then (without my tables handy so check before you undertake the job) I'd imagine 190x45 or 240x45 F17 LVL at 450 centres supported by the I beam in the middle and a waling plate on the garage walls set with Hilti Chemset or Dyna Bolts. Normal chipboard yellow tongue flooring on the top and a ladder to access and you're set.

It all depends on the position and the rating of the I beam of course. If it's not a strong beam then it may not be worth putting extra dead load on it. If it is up at the peak of the roof then you can't really hang much off of it, and then your timber would be spanning 6.8m in which case you'd be looking at steel as a most economical mode to span such a distance.

[bazza91]

It all depends on money and how much weight you need to support.

Maybe something like this:

Have a look at these guys and steal/borrow their ideas http://www.smartgarage4u.com/

They look pretty damn strong.

[Crazy Dazz]

Originally Posted by bazza91

It all depends on money and how much weight you need to support.


They look pretty damn strong.

Wow, that looks awesome, but what are they hanging on??? Must have some awesome anchors in that ceiling!

[Crazy Dazz]

Originally Posted by Danny

If it's spanning 6.8m and there is an I beam in the middle then whatever members you use will be spanning 3.4m only.

For storage only you won't need hugely rated members unless you're storing really heavy stuff or wanting to live up there, then (without my tables handy so check before you undertake the job) I'd imagine 190x45 or 240x45 F17 LVL at 450 centres supported by the I beam in the middle and a waling plate on the garage walls set with Hilti Chemset or Dyna Bolts. Normal chipboard yellow tongue flooring on the top and a ladder to access and you're set.

It all depends on the position and the rating of the I beam of course. If it's not a strong beam then it may not be worth putting extra dead load on it. If it is up at the peak of the roof then you can't really hang much off of it, and then your timber would be spanning 6.8m in which case you'd be looking at steel as a most economical mode to span such a distance.

The I beam is massive, it spans the Garage lengthways (if that makes sense) and is somewhere 8~9m long. So I can't imagine my few boxes of stuff are going to be a big issue. Couple of Girder Brackets and suitable rods...
My reading of the tables (floor/deck) is that with MGP10, 190*45 (35) should be enough to span 3.5m?

[bazza91]

I imagine they have some high tensile bolts running right through the roof trusses. Its bloody impressive though.

[zilo]

MGP10 with 450mm spacing with yellowtongue at right angles to it will easily do it.

You could just buy some C150 purlins then yellowtongue and do it much easier and look far better too....probably cheaper.

Make the stairs with purlins too.

[sr71]

Originally Posted by zilo

MGP10 with 450mm spacing with yellowtongue at right angles to it will easily do it.

You could just buy some C150 purlins then yellowtongue and do it much easier and look far better too....probably cheaper.

Yeh, the C purlins will be cheaper. When ordering, they can help you choose the size and thickness(gauge) of rolled purlin.
Connecting to the beam will be best if approx. 90 x 90 plates(with hole for bolt) are welded on. And order C purlins with hole in one end.
And the other ends can be supported with your Carpentry: A stud wall, braced and blocked above Top Plate, to secure/fix to C purlins.
Your beam might need a Column or 2 , to prevent it failing under the new load.
Something like a 89 x 89 SHS with plates welded top and bottom, and bolted in place.
I recall a job designed for 3kN/m2. ( Same as a car park, forklifts etc) . The I beam was 440 (?) deep, with a Single Span of 10m. It had 25mm ply floor, internal beams and C Purlins(about 3.4 metres). You only need to design for 1kn/m2 (1 tonne per m2).

The Smart shelves would need additional Structural Support in the roof space. Bolts and/or brackets need to work under tension. But ceiling framework is only designed to support gyprock ceiling, roofing material plus a bit more for safety factors. Adding 100's of kilos will bow the ceiling and roof, without a big beam above the ceiling joists stiffening the structural frame.