Help Sizing LVL Beam for Mezzanine

[jacobm99]

I'm looking to build a mezzanine in my garage that is 15' wide. The mezzanine would span 12' deep, but the LVL span tables online start at 20' spans. Does anyone know of any tables that would tell me what size LVL I should use? I'll be storing car parts and other heavy items (cherry picker, tube bender, rotisserie).

 

[8mpg]

Just talk to your lumber yard. They will often calculate it for free as part of selling the beam.

 

[GMCGarage]

Try weyerhauser website

 

[red]

Like 8mpg said your supplier will have the correct info.
Not sure if this will help with what you're looking for-

http://www.weyerhaeuser.com/woodproducts/document-library/tb-551

 

[bczygan]

Let's do it. Let's design the whole mezzanine.

Start with the floor sheathing. I like 3/4" T&G plywood, glued and screwed and staggered for the decking. Run perpendicular to the joists and provide solid blocking under all seams.

Joists I like to space at a maximum of 16" on center, to support the floor sheathing properly. I use this calculator for sizing joists:
http://www.awc.org/codes-standards/calculators-software/spancalc

A 40#/SF live load is typical for residential floors. This should be adequate for what you describe. Using that, and a 10#/SF dead load, Spruce-Pine-Fir for material and a deflection limit of L/360, 2x6's will span 9'-5". The actual span is 9'-6", so this will work.

The beam has a contributing area of 6SF x 50#/SF total load, for a total load of 300#/LF. The LL is 240#/LF. I use this chart to size LVL's: https://parr.com/PDFs/LP%20LVL%201.9E.pdf

Using a readily available 1.9E LVL, a double 11 1/4" deep LVL beam will support a LL of 284#/LF and a total load of 416#/LF, so this is more than adequate. Support with a 4x4 post or 3 2x4's as columns in the walls.

The ledger along the wall needs design as well. I would lag it into every stud, but I also like to support it at both ends and in the middle, with a stud laid flat against the wall and lagged into a stud. This cuts the span in half so you can use a smaller beam. Dimensional lumber will work here. I use this chart:http://www.awc.org/pdf/codes-standards/publications/wsdd/AWC-WSDD1986-ViewOnly-0301.pdf A 15' long 2x12 will span the two 7 1/2' spans and support a 362#/LF total load at a L/360 deflection limit, so this will do.

Understand?

Bill

 

[theoldwizard1]

Weyerhaeuser span tables

 

[GMCGarage]

Let's do it. Let's design the whole mezzanine.

Start with the floor sheathing. I like 3/4" T&G plywood, glued and screwed and staggered for the decking. Run perpendicular to the joists and provide solid blocking under all seams.

Joists I like to space at a maximum of 16" on center, to support the floor sheathing properly. I use this calculator for sizing joists:
http://www.awc.org/codes-standards/calculators-software/spancalc

A 40#/SF live load is typical for residential floors. This should be adequate for what you describe. Using that, and a 10#/SF dead load, Spruce-Pine-Fir for material and a deflection limit of L/360, 2x6's will span 9'-5". The actual span is 9'-6", so this will work.

The beam has a contributing area of 6SF x 50#/SF total load, for a total load of 300#/LF. The LL is 240#/LF. I use this chart to size LVL's: https://parr.com/PDFs/LP%20LVL%201.9E.pdf

Using a readily available 1.9E LVL, a double 11 1/4" deep LVL beam will support a LL of 284#/LF and a total load of 416#/LF, so this is more than adequate. Support with a 4x4 post or 3 2x4's as columns in the walls.

The ledger along the wall needs design as well. I would lag it into every stud, but I also like to support it at both ends and in the middle, with a stud laid flat against the wall and lagged into a stud. This cuts the span in half so you can use a smaller beam. Dimensional lumber will work here. I use this chart:http://www.awc.org/pdf/codes-standards/publications/wsdd/AWC-WSDD1986-ViewOnly-0301.pdf A 15' long 2x12 will span the two 7 1/2' spans and support a 362#/LF total load at a L/360 deflection limit, so this will do.

Understand?

Bill

where did you get 9'-6" span for the joist, are they not 12'-0"?

 

[73RR]

...looks to me that the deck is 12 x 15......

 

[jacobm99]

Thanks everyone, especially bczygan. I had been researching this and saw that you are the resident expert and was hoping you would weigh in. Appreciate you taking the time to map out the entire design.

Regarding the joist span, as others have said, the mezzanine will be 12’ deep. Which, according to the above calculator, means I will need to run 2x8 joists 16” on center.

As to the beam, looking at the weyerhauser tables, it appears I can go with any of the following options:
• Doubled up 1 ¾” x 11 ¼” LVL
• Single 3 ½” x 11 ¼” LVL
• Single 5 ¼” x 9 ½” LVL

Anyone see things differently?

 

[GMCGarage]

Thanks everyone, especially bczygan. I had been researching this and saw that you are the resident expert and was hoping you would weigh in. Appreciate you taking the time to map out the entire design.

Regarding the joist span, as others have said, the mezzanine will be 12’ deep. Which, according to the above calculator, means I will need to run 2x8 joists 16” on center.

As to the beam, looking at the weyerhauser tables, it appears I can go with any of the following options:
• Doubled up 1 ¾” x 11 ¼” LVL
• Single 3 ½” x 11 ¼” LVL
• Single 5 ¼” x 9 ½” LVL

Anyone see things differently?

Looks good. Are you satisfied with 40psf storage load? For the small amount of lumber you might want to up that. All depends what you are going to put up there.

 

[matt_i]

A mentor of mine once said.....figure out what you need right now and then double it. A good technical mind will figure out how to use the extra capacity in the future

 

[jacobm99]

About half of the footprint will be taken up by my tops for my 72 blazer and my 69 corvette, both of which are relatively light in terms of pounds per square foot, so i think 40psf should be fine.

 

[Virgil Tech]

NO, absolutely NO!
You MUST write a check to a Licensed Professional Engineer so he can generate drawings and stamp them.

OE, send me $100 cash and I'll send you back a drawing with a forever stamp on it that you can use to mail a letter.

 

[bczygan]

My bad!!!!!!!

I screwed up the joists!

Thank you GMCGarage!

So using #2 and better SPF 2x8's at 16"o.c. will span 12'3"!

Always worth checking your work!!!

And to the OP, the double 11 1/4" deep LVL will work best for the beam because you can lift each ply up separately and then fasten them together.

Bill

 

[GMCGarage]

NO, absolutely NO!
You MUST write a check to a Licensed Professional Engineer so he can generate drawings and stamp them.

OE, send me $100 cash and I'll send you back a drawing with a forever stamp on it that you can use to mail a letter.

Hi and Bye Franz!

 

[acer66]

Just talk to your lumber yard. They will often calculate it for free as part of selling the beam.

This.

 

[Fatboy148]

And to the OP, the double 11 1/4" deep LVL will work best for the beam because you can lift each ply up separately and then fasten them together.

Bill

Totally agree!

To the OP... With your partner, keep the LVL as level as possible, taking it up to place it on the supports or one end will get heavy, real fast! Ask anyone that has been on the heavy end.

Fastening the LVL's together along with the fasteners to be used and the fastening pattern for the ledger board to the studs on the opposite end may be another study in itself.

You could also pick up a little more strength in your floor (more carrying capacity/less bounce) while using the same components by holding the LVL's back some (cantilevering up to 1/3 of the depth) and using them a support under your floor joists instead of using hangers and nailing into the end of the joists. Doing so would however lower your head room on the ground floor by 11 1/4" where the beam goes across. Just another thought....

 

[jacobm99]

To the OP... With your partner, keep the LVL as level as possible, taking it up to place it on the supports or one end will get heavy, real fast! Ask anyone that has been on the heavy end.

Thanks for the advice. Does anyone know where I can find how much LVLs weigh per foot?

 

[matt_i]

This table should give some ideas.

http://www.westfraser.com/sites/default/files/products/LVL/LVL Users Guide - Canada v0415.pdf

Looks like a 1-3/4" thick x 11-1/2" tall is 5.7 lbs/linear foot just for reference. They are heavy and hard to hand-drive nails into. You will get a workout driving nails by hand to sister two beams together. However they are great timbers in my estimation, straight, stable, and well worth their extra cost when you need the additional structure.

 

[IPACA9]

Looks like a 1-3/4" thick x 11-1/2" tall is 5.7 lbs/linear foot just for reference. They are heavy and hard to hand-drive nails into. You will get a workout driving nails by hand to sister two beams together. However they are great timbers in my estimation, straight, stable, and well worth their extra cost when you need the additional structure.

Just happened to see this.

For attaching my LVL beams together I chose Fastenmaster's TrussLoks which have now been replaced with a different flatter head version similar to the HeadLock screws. They are designed to sister the beams together and will pull them tight.




Sent from my XT1585 using Tapatalk

 

[2point2]

The beam has a contributing area of 6SF x 50#/SF total load, for a total load of 300#/LF.

Hey bczygan,

Where does the "6SF" come from? What does 'contributing area' means...

Please and Thanks!