20x40 Mezzanine

[Hooksdj]

I have a 40x60 shop on which one end I want to put a mezzanine up in. I would like the underneth to be as open as possible. That being said, I am setting this up on one end of the shop so the wall will be one side of mezzanine. Post on the wall side have a 8x8 on each corner and 2 ea. 8x8 14' and 12' (making up the 40' length. The other end of the mezzanine will be the open shop area. I plan on putting up 2 ea. 6x6 post set at the same distance as the 14' and 12' post on the wall side. I am planning on running 2x12 as joist the entire 20' span. I have been told I would have to use some rather heavy sawn lumber of 8x10 or maybe 10x12. My question, I was hoping to use 3 or 4 ea. 2x12 sandwiched with 1/2 plywood in between. Fastened together with glue, and 3/8 bolts.

Am I on the right track here?

 

[cyamaha2007]

Well im no engineer but are you trying to clear span 40ft? Look up how to make a header with dimensional lumber. That will give you a nail pattern nail type and such.

 

[Hooksdj]

Here is a layout of what I was thinking. I could either build the beam in multiple sections and have them met half way overtop the 6x6 beams or just make the beam continuous and set atop the 6x6 beams. Note The number of joist shown in the drawing is just to represent the direction of them. There will be many more than what is shown in my drawing.

 

[Justanoldguy]

are you trying to clear span 40ft? .

Did you even READ his post?

 

[zcar751]

You didn't mention what you want to put on the mezzanine. This is critical as you will need it to be load rated. No reason to put up something that will only hold 40 lbs per square foot. Also critical is where you live, is it a commercial property, are you running a business from this location. You may have permitting issues, need a professional engineer to sign of on drawings.
If you don't need any of that I would talk to someone who make trusses and tell them the span you want to cover and they can provide you with suggestions as to beams, post and securing options. Personally, I would look at floor trusses. they will easily clear a twenty foot span. Other options include engineered beams.
Take the time to do it right because you don't want it to cave in on you one day.

 

[cyamaha2007]

Did you even READ his post?

I guess not, no idea what the hell i was smokin.

 

[Hooksdj]

At the moment it will only hold a gym with a bathroom and basic storage, nothing to awfully heavy. Later I do intend on making some sort of living quarters for my kid/s when they get older and hopefully go to college.

 

[ADSR]

I build houses for a living. Don't even play around with it if it will support life. Just put in a call to a local truss builder and ask them your options. They will tell you what to use for free. I've seen guys put in HUGE beams and spend way more time and money than they needed to, only to find they could have done much better with a smaller, lighter gang truss.

 

[sasky]

I have a 40x60 with mez across back wall. Not slot to it. Busy working right now but sounds like rain by the weekend. I can take some pics if u like

 

[dbonne]

I just built a Mezz half the size you are talking, I spanned 18'. I used I-Joists as they have better load cap than dimensional lumber. Take a look here for span and loading charts.

http://www.internationalbeams.com/i-joists/

 

[larry_g]

I have something similar. Check out my build link below. My mez is 12x36.

lg
no neat sig line

 

[Hooksdj]

I had a engineer runs some calculations for me but it looks like he went a bit overboard. Ive gone back to him a few times but the responses do not help me much. He Has listed 8x12 sawn lumber for my beams and then 2x12 equivalent I joist topped by 1" 1/4" t&g plywood. I'm thinking of using 4 ea 2x12" glued and bolted together together to get my beam dimension, then use 2x12 as my joist topped by 3/4" OSB or Plywood. With the A room going in underneath i was thinking it could add support as well. I'm out of the country now but will post some pics upon returning home. Any pics anyone has to offer would be appreciated.