# Forum Home Renovation The Garden Shed  Garage mezzanine floor.

## Bart

Gday all, hope all is ok.
I need some help on building a mezzanine floor in my shed to increase my storage. Any idea on how to construct a mezzanine? I want to basically make it on the back right hand corner of the garage, I'm having trouble finding a garage company to do it, I assume its a too smaller job for them to bother. I was thinking of using C Purlins, also didnt want to use a post in the middle of the garage to hold up the mezzanine so I guess this means I would have to span a largish C Purlin down the centre of the garage, 5.6m length, from the back upright to the front upright and span smaller C Prulins from that to the right of the garage. Mezzanine should be approx same height as the guttering. Mezzanine floor, 4.2m wide (from centre of garage to right side of garage), X 2.9m deep.
Any ideas on size of Purlins? I was thinking 300-400mm for the Purlin down the centre and 150mm for the purlins to span from the centre to the right of the garage.<!-- google_ad_section_end -->   <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com :Shock: ffice :Shock: ffice" /><o :Tongue: ></o :Tongue: > <o :Tongue: ></o :Tongue: > <o :Tongue: ></o :Tongue: >

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## Shedblog.com.au

Hi, what sort of load do you intend to place on the Mezz floor? 
The main reason that some shed suppliers dont look at mezzanine floors for people is that they didnt build the original shed. This can introduce engineering problems.  
Reputable accredited suppliers follow strict guidelines and the addition of the mezz floor impacts on the original sheds engineering.  
Could the supplier of the original building not help? 
As a guide...
The centre bearer between the the two centre columns I would expect to use a Cee 300 1.9 or 2.4mm BMT with the joists being Cee 150 1.9mm  
Dave

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## Bloss

By far the easiest way is to simply build a shed within a shed - ie: a box that stands alone with the shed being attached to simply to provide a little lateral support. That can be done using steel, but for most DIYers timber is easier and cheaper. So a frame at each end - effectively for posts with some bracing in between which can be speed brace or timber and then two beams one at the back one at the front - most likely supported by a centre post in each one so the span is more reasonable and depth of beam can be reduced. Then ceiling/floor joists sitting on top of the beams (=bearers) or sitting in joist hangars attached to the beams. Then a floor of particle board (ie: "yellow tongue", structafloor etc). 
The centre post could go floor to ceiling and attach to the shed frame (and bolted to floor using brackets ankascrewed or dynabolted to the floor - again to simply provide some lateral stability - the majority of load goes to the floor as downforce. The attached pic shows the sort of thing I mean - in this case the client wanted an office within the shed and a mezzanine storage area above so the two frames were built as shown. In this case 15mm ply was attached to the steel frame and on the wall a ledger was then screwed into the ply and the joist then ran from that side wall to the centre frame and yellow tongue was placed across the joists to form the floor/ ceiling. 
In your case top plate in this pic is replaced by the front cross beam which could span all the way across running in front of or behind the centre post to which it would be bolted or could be two shorter beams sitting on brackets and abutting the centre post. Of course you could simply copy the type in the pic in just the one corner - the wall frame can be open so you can step through - you could brace using a ply angle at the top front and back top.

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## pinger

The simple fact is that normal domestic sheds are not designed to carry dead loads- so that is why the shed company will not be keen to become involved.  
People are not prepared to pay for the engineering to engineer a mezzanine, so again a shed company is in a position where they usually walk away.

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## Bloss

Which is why you build, a shed within a shed . . . a freestanding structure transferring very light loads only to the steel frame. My post above is using timber, but if you were used to using steel or preferred to anyway then steel would be fine too - but the same principle - a largely independent structure.  :2thumbsup:

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## Burf72

Couple of pictures that might help of the set up i used in my Shed, main beam that I used was some 150 x 75 I Beam joined and bolted in the middle with the same I beam post, also made up some C Channel posts for the ends to take the strain off the shed frame, also used 140 x 45 timbers which was enough for the 3m span as it was only a storage area with partical board flooring. Still plan to run it out another 3m bay with a similar set up, starting to fill this area up already.

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## r3nov8or

Hey Burf72, like the way you are filling it up with gym, bar furniture, couch, TV etc. The next bay could cater for the home brew and bathroom and you'll never have to leave.  :Smilie:

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## Burf72

Thats the plan home away from home, currently renovating the house so we spend a bit of time down in the shed while that is all going on, will be good to get a bit of room back in the shed once the house is all done and furniture moved back.

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## Bloss

> Couple of pictures that might help of the set up i used in my Shed, main beam that I used was some 150 x 75 I Beam joined and bolted in the middle with the same I beam post, also made up some C Channel posts for the ends to take the strain off the shed frame, also used 140 x 45 timbers which was enough for the 3m span as it was only a storage area with partical board flooring. Still plan to run it out another 3m bay with a similar set up, starting to fill this area up already.

  Yep - basically a structure that is designed to carry its own weight & loads added - not placing much if any load on the steel shed covering it.  :2thumbsup:

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## Draffa

I'm a total newbie, but you may want to consider pallet racking.  A two-pallet span is usually rated for 2500kg, so more then enough for most residential use.  The local Repco has an mezzanine of about 20*10m built using the racking.

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## Bart

Thought i would log in and check out this forum again and.......
Holy crap i didnt realise i got such a response.
I know this is late but thanks for your replies everyone.

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## Jim Carroll

So show us pics of what you did

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## Bart

> So show us pics of what you did

  Jim i wish i could, i have been so bogged down with the house reno i havent had the time or money to build the mezzanine but when i do i will post some pics. I promise i wont leave for a whole year again
Actually ill need other advice from this great forum

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## BarneySSS

> Couple of pictures that might help of the set up i used in my Shed, main beam that I used was some 150 x 75 I Beam joined and bolted in the middle with the same I beam post, also made up some C Channel posts for the ends to take the strain off the shed frame, also used 140 x 45 timbers which was enough for the 3m span as it was only a storage area with partical board flooring. Still plan to run it out another 3m bay with a similar set up, starting to fill this area up already.

  G'day Burf
I have a 6m x 12m shed at home and am looking at enclosing one end 3m wide bay into a 'clean room' to house computer, desk, filing cabinets, and clean assembly area for engine and gearbox final assembly ( I have a couple of old rally cars to play with).  I want to build it as a mezzanine so I can store our rarely used home wares such as xmas decorations, boxes of books and other crap that we collect and rarely use.  It will be self supported with uprights bolted to shed frame just for stability. 
I saw your pics and would be keen to hear the full plan if you don't mind. 
Would also appreciate any advice from other forum members for design of this room. 
Thanks
Barney

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