Size beam?

[punkin25]

I'm in the process of building my pole barn house and want to avoid putting a post in the middle of my garage if I can. The garage area of the house will be 28'x32' with the support beam spanning the 28 ft direction. There will be bedrooms only above this area and the roof trusses will be free span trusses so none of the walls in the second level should be considered load bearing? I scored some surplus engineered floor trusses that are 16ft long and the ends will rest on top of this beam.

84 Lumber said that I needed 3 ply LVL @ 24" deep. I can't spare that much head room. So I am looking to size a steel beam. I sketched my own plans so I am having trouble getting a structural engineer to help. I have ran some numbers myself using formulas from internet searches but I don't trust my calculations. Anyone on here can make a suggestion on beam size or point me in the right direction to get the help I need?

This is my first post so I guess I will introduce myself. Electrical engineer by trade and work in the steel industry. Tired of living in a subdivision so, the family and I are moving back home to family owned property. I'm building this pole barn house as time and money permits. I will start a build thread soon and post some pics. I've got a lot of plans and ideas based off this site! Thanks to all you guys that have shared your builds!

 

[punkin25]

Oh yeah, l'm located in NW Alabama. Roll Tide!

 

[Nowater]

Walls that run parallel to the beams need a beam under them or else the flooring will sag under the weight of the wall.

Often, a live load of 40 pounds per square foot is used along with a dead load value. Take all the square feet supported by the beam and multiply by the loads. Where it applies, the outside walls hold half of the weight. That is what your beam needs to hold up. Twenty eight feet is a long span to hold up large loads.

The load bearing ability of beams increases geometrically with their depth.

Other people would try to span the 28' direction with trusses and not use a central beam. Your 16' recycled trusses may not be worth using, sorry to say. A problem with long spans can be the deflection from live loads. It makes people feel uneasy walking on the floor. There are three commonly used deflection formulas, use the most restrictive one!

Have you looked into the wood I beams? You may be able to span the 28' distance with a lighter weight beam that would conserve headroom.

 

[kbs2244]

Sell the 16 footers and buy the right ones.

 

[punkin25]

Nevermind guys. I figured out my mistake in running the numbers. It's a W12x45. 747 bucks after tax locally for a 28ft stick. Well worth not having the post in the center of my garage.