Changing Beam Thickness - Over A 2"x4" Top Plate

personalt

I am framing a room where there is a beam that runs from top to back. It crosses a wall that divides the span into a 20 foot span and a 12 foot span.

Engineer has the back part of the beam made up of (4) 1 3/4" x 11 1/4" lvls
and the front part made up of (1) 3 1/2 x 11 1/4 LVL.

I mostly build row houses that are 20-25' wide, so any time I do a beam I get a 20 foot length and go right across the top plate. However this house the span is about 45 feet made up of a few differnt beams

1. I feel wierd having each beam sit on what is really half of a couple of 2"x4". Should I be concerned about that?

2. Can any recommend a simpons or usp product for the connection point? I was thinking a strap or nailing plate over the top since they are both the same height and would be flush at the top. And I was thinking of an angle or rafter tie type connector in addtion to toe-nailing it to stop and sideways movement/twisting.

pkp

field mods usually bite me in the rear more than they help. I wouldn't change anything unless you know the inspector already and you know how he feels about field mods.

If they are not stock prints why not call the engineer?

Just remember, if you change anything, it's your bond that is on the line, if you leave it alone it's his bond. I only change stuff if it is obvious that the engineer screwed up. Or, depending on the inspector I am dealing with, I may call the engineer and make him fix it.

personalt

I totally agree... making a field mod puts in my a bad spot..

I dont think I really want to change anything.

My concern at this point is what is the best to secure the beam as it changes sizes over a 2"x4" top plate?

Simpson has a bracket can can be used to join to beams but it wraps the beam so both must be of the same thickness

I go from a 3 1/2" x 11 7/8" lvl to a 5 1/4" x 11 7/8" lvl. The beams are to be placed flush on the 'outside' so I was thiking a flat peice of steel where the two beams come together would be helpful.

engineer is not helpful as I have to go through the archtect and he engineer seems to be on vacation or something as architect has been trying to get my an answer for almost two weeks now.

Anyone with comments on if splitting a beam over a 2"x4" top plate is a okay?

skyhook

Nail a strap (ST 18 or better) to the top plate first, them place your beams, finish nailing the strap underneath and add ST to top of beam connection. Just a suggestion, never had a inspector shoot me down for extra chrome.

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personalt

that sounds like a good idea to me..

KentWhitten

the strap on the underside sounds good. The rocker might not like it though. Maybe on the side so it's out of everyones way, near the bottom 1/3 of the beam.

I never liked it like that either. I usually broke the 3 -1/2" down to (2) 1-3/4's and ran them full length. Your case, It'd be a heavy one. Strapping would be much easier.

I'd also call the engineer and really the inspector covering your job to see if it's OK. Like skyhook said, the more metal, they like it.

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mighty anvil

The ends of the beams must be braced laterally and tied down as well as together and that should be detailed by the engineer of record. Be sure the bearing is sufficient; it seems skimpy to me.

The engineer will probably require at least a post cap of some kind like a Simpson PC84 or PCE84. I suspect the support below would be a 4x6 PSL post rather than multiple studs.

4 LVLs usually must be bolted together. Be sure to follow the manufacturer's instructions.