Mezzanine Design

[pstreccius]

I've got an existing structure built to store an RV that we have converted into a livable space. One stall of the building has 16ft ceilings and I'd like to build a mezzanine in the back for a home office. Walls are 2x6 construction on footers. I am hoping to build a 10x17 mezzanine/loft. Have a mocked picture attached, please excuse the mess. Will 2x10s spaced 16 O.C. be sufficient? My other question is what size beam/LVL will I need to span the 17 ft with a single post (6x6) placed at 14 ft? I hope to build the beam into the wall/drywall by Kingstudding it with 3-4 2x6s stacked as support. Am I crazy?

 

[firebirdparts]

2 by 10's are very adequate for 10'

I think your king stud will be fine, but I did not do any calcs are all.

Is this a stick built building with studs? You need that to have a ledger board (the ledger board needs the ledge to exist).

 

[pstreccius]

Yes stick built, walls are 2x6. Plan was to lag the ledger to the studs and also run 2 or 3 vertical support 2x6 flat to the wall under the ledger.

 

[NUTTSGT]

Are you going to remove the drywall where the vertical studs and ledger are ?

 

[Hank11]

Is your office upstairs or downstairs? And what about stairs? Where are they?

 

[pstreccius]

Will remove the drywall if that is necessary, was planning to go over the top of it with ledger, and run verticals on top of studs. For stairs the plan is to do attic style stairs that fold down and up. I’ll likely use a ladder until I come up with something better. Trying to preserve as much floor space as possible.

 

[Hank11]

So office down and storage up?

I would tend to preserve headspace wherever I thought I would spend the most time or do the most work.

 

[pstreccius]

Office will be upstairs. Going to aim for 7.5 feet floor plate to ceiling

 

[pstreccius]

If I can get away with a 6x14 Glulam with a single post at ~14 feet from the king stud and run 2x10s at 16oc w/ 3/4 subfloor, by my measure I can get 8ft ground clearance from the studs (7'8" under glulam) leaving ~7'2" for the office space. The office would have most of the time sitting at a desk and the ground floor is used daily.

 

[mike93lx]

6" glulam hits me as quite wide.

At only 10ft, I think I'd do 2x8 to get a couple more inches of headroom. Also, you are planning to hang the joists off the beam, correct? No need to put them on top

 

[pstreccius]

Got it, I wasnt sure of I could get away with 8s, if so, yes the more space the better. Will hang off the joint with hangers, Beam outer face will be right at 10 feet.

Edit: Was going 6in because I figure I need a 6x6 support post. Is a 4x14(or smaller if I can find a 12 or 10) with a 4x4 support post sufficient?

 

[mike93lx]

I can't comment on what size is needed, but I would build with a 6x6. Just thought a 6" glulam felt big. May not be

Check span tables on the joists, before you pick a size. I would go 12OC if it meant being able to go with a shorter joist

 

[pstreccius]

I got in touch with someone much smarter than I (engineer). He shared the following info:
- 2x8s at 12 o.c. with a 4x9 Glulam and steel support post I'll be at 63psf
- 2x12s at 12 o.c. with a 4x12 glulam and steel support would be at 110 psf

both cases I'll need to pour a footing for the post, was advised 21x21x9" under current slab.
Given 63psf should give me an approx total load of ~9000 lbs I can't for see needing more than than for an office and maybe some tote storage at some point.

 

[mike93lx]

Unless a safe or aquarium is going up there, I bet you would be fine at 63psf. Headroom ftw

 

[Jon h]

Yes stick built, walls are 2x6. Plan was to lag the ledger to the studs and also run 2 or 3 vertical support 2x6 flat to the wall under the ledger.

That’s exactly what I did when I built mine.