Return to the Remodeling Forum | Post a Follow-Up

How to install a flush laminate beam?

Posted by weedyacres (My Page) on
Sat, May 17, 08 at 19:02

We're rearranging our upstairs walls a bit to add a bathroom between two bedrooms. Here are the prints. Note the dotted line, which is the current load-bearing wall.

The prints call for it to be replaced with a flush laminated beam, which, if I understand correctly, means putting a beam above the ceiling, suspended from the joists on either end, and then hanging the floor joists of the room above to that beam.

We're DIY-ing this, so want to make sure that we're executing it correctly. We've pulled the drywall off the LB wall, and it's just 2x4s. Up in the attic, the joists are 2x6s spanning the "new bedroom" and 2x8s spanning "bedroom #3", and they intersect and rest on the 2x4 LB wall. Here's a photo showing the intersection above the LB wall. The board in the lower right is just the frame for the attic access panel.

And here's a couple shots of the attic. We want to eventually finish it into a 20x20 room, which will require beefing up the floor joists to 2x12s.

So back to the laminate beam. Our thought on how to install it is to build the 2 outside bathroom walls to provide temporary support for the joists. Then climb up in the attic, cut the joists off so that a beam can fit between them, hang the beam to the joists on the outside wall and the inside wall, then hang the just-cut joists to the just-installed beam.

Are we in the neighborhood here, or completely off-base?

Follow-Up Postings:

RE: How to install a flush laminate beam?

Is the new beam sized properly for it's future use- carrying the new 2x12's for living space, or just sized to carry ceiling joists for an attic? No point in doing the latter if it has to be re-engineered down the road.
I would do the work from below, not above. I'd get some temporary walls in first,about four feet apart; cut out 3 feet of ceiling, and fit the new girder from below. IMO it's much easier to lift it in than to deal with moving wires so it can drop in.
Allow an extra quarter inch when trimming the ceiling joists. Put a nail in every hole of each joist hanger. It's easy.
The point loads at either end of the girder must bear through to foundation. Look at what you have at the stair well- a rim joist is okay, too, but not a double plate by itelf.

RE: How to install a flush laminate beam?

Need more information. The Porch Guy

RE: How to install a flush laminate beam?

The beam should be sized for a live load in the attic (they did plans for the bath as well as new stairs/attic), but I'll double check. I never thought about installing from below. That helps with the "how the heck do we get a 25-foot beam up into the attic through an itty bitty hole" question.

I'll go up in the attic again and see what's at the stairwell.

porch guy: what other info do you need?

RE: How to install a flush laminate beam?

Fine Homebuilding number 152, January, 2003, page 80, has an article, "Removing a Bearing Wall", in which they install a beam in the ceiling, just as you want to do. Go to, seach for "Removing a Bearing Wall" to locate the article, but to view it you need to become a member, though they offer a free trial.


RE: How to install a flush laminate beam?

What you propose cannot be done.

1st, the lam beam cannot be 'suspended from the joists on either end'. Beams and girders must be be supported on each end by structural columns which transfer their weight directly to the foundations and footings.

2nd, a lam beam needs to be engineered (by an engineer) to carry all loads placed upon it.

3rd, the size of the ceiling joists for the approximately 18ft + spans must be at least (generally speaking) 2x10s or deeper at 16" on center to carry the ceiling loads.


The bottom line is that no one here can help you and you will need to engage the services of an engineer or other design professional help you.

RE: How to install a flush laminate beam?

We did hire a design pro who drew the plans and consulted an engineer. My DH called them back and they confirmed that the beam is sized to support the live load in the future finished attic. And we can make it just 13' long (the length of the wall we're removing), and use headers across the last 7 feet or so (2 doorways).

On more crawling around in said attic, I realize that I misspoke on how said beam will be supported. It will rest on the outside wall of the house and an interior load bearing wall. We'll then hang the joists from the beam.

So we're off to buy a lam beam and get to work. Thanks a million bill v for the article (duly joined/saved/soaked up like a sponge) and sombreuil for your tips on doing it from below.

RE: How to install a flush laminate beam?

I'm happy to report that we've got our beam in! DH and DSS did it with a lot of sweat.
1. After putting up temporary support walls, DH cut the LB wall out as well as the two joists, creating the gap for the beam.

2. DSS handed him up the beam in 2 parts, he bolted it together with lag bolts every 2 feet, and set it in place on the rim joist and another LB wall 20 feet away.

3. DH attached all 43 joists to the lam beam with joist hangers while DSS watched and they bonded.

Anything that looks wrong before we remove the supporting walls and button up the ceiling drywall again?

RE: How to install a flush laminate beam?

Good job. Looks fine. Hot in that attic, eh?

RE: How to install a flush laminate beam?

Whooeeee, hot doesn't begin to describe it. DH was wringing sweat out of his jeans by the end.

While the ceiling was opened up, we fed up a bunch of polyiso insulating panels that we're going to attach to the rafters. Eventually (next year?) we're going to finish the attic space.

 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Remodeling Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here