Beam to support ceiling joists

[starck]

I am remodeling a home and need to remove a bearing wall that is supporting the 2x6, 16oc spacing ceiling joists. The span will be 16'. The house is a single story and the roof is stick framed with the weight of the roof on the exterior walls. The walls I want to remove run down the middle of the house.

I talked briefly with the structural engineer I had used before about my plan for supporting the ceiling, which is to lay a beam on the top of the ceiling joists supported by posts that sit on top of the main support beam for the floor.

He said that it would work and mentioned using a 4"x12" D.Fir beam.

After thinking about it I would like to use a Glued Laminate beam instead (it smaller and easier to get up there above the ceiling.

Q: Is there a coversion table I can use that would allow me to go from a D.Fir beam to a GL?

Q: The ceiling joist would lap a 10 inches away from this new beam for approx 5' (or ~4 joists). Should I also add angled 2x6 supports from the lap joint to the rafters to support this area?

Thanks in advance,

Dave

 

[swBausch]

If 4x12 would work, you could use two 2x12s, each being easier to handle. Bring them up separately, and nail/bolt them together when up in the attic.

 

[ERV]

Glue-lams are known as engineered lumber and as such, proper sizing should be left up to a qualified structural engineer.
I don't know all the parameters of your ceiling situation, however, a 4X12 DF beam spanning 16' seems overspan. 2-2X12's are defenitely overspanned and will cause sagging and long term creep (not to mention how to properly conect the two for adequate load transfer).
Setting a beam over (above) members to be supported presents another problem of proper connection to the supporting beam (connections would be in tension).
Save yourself a lot of headaches and hire a local structural engineering for proper beam sizing and connection details .The cost is worth the piece of mind that your ceiling won't come crashing down on you and your family.

 

[boo1]

AITC Conversion Tables AITC Conversion Tables provide glulam member sizes that can be substituted for beams of sawn lumber, structural composite lumber, or steel.

Found at:

https://www.aitc-glulam.org/TechnicalInfo/tables.asp?type=Conversion

Often the details are the most neglected parts of a beam design. E.I. bearing, straps, attachment .....

 

[starck]

Thanks for the replies.

Besides the beam issue, I also have the issue of the ceiling joist lapping ~10" from where the beam would be.

If anyone has any suggestions I'd appreciate it.

Also I will call the structural engineer back today and ask him to run load calcs for me and give me different options.

I don't want to have to re-address this issue in the future because I didn't take time to get it right now.

Thanks, Dave

 

[starck]

Thanks again for the feedback. I had load calcs done for the beam and my Structural Engineer specified a 5.25 x 9.5 Parallam (PSL) with TS9 (Simpson) Twist straps to tie the members to the beam and Simpson ST5515 straps to tie the beam to the supports.

Glad I checked.

Dave.

 

[starck]

CORRECTION: That should be Simpson ST2215 straps NOT ST5515