Opening a load bearing wall

[sundoy]

I am planning on opening an exterior load bearing wall to join a new addition to my existing kitchen. The current wall is 2x6 24 OC framing and currently has a window and door in it (which will be removed). The new opening will span about 15 feet (from the outside of the existing window to the outside of the existing door). I plan to have a post support at each end and one in the middle. I have a few LVLs available to me and would like to know the minimum size sufficient to carry the load. There is a second floor and roof load to consider (no walk up attic). I am located in Central Massachusetts so snow loads are also a consideration. I plan to have the new beam sit under the top plate of the wall an thus carry the above floor joist from underneath.

Assume I am using 2 LVLs what is the minimum size (each) that can be used?

[Doug Aleshire]

sundoy.

I'd recommend use 3 - 1/3/4" x 14" CLEAR SPAN. Using 2 - 1 3/4 x 11 1/4" would be WITH CENTER POST or 3- 1 3/4" x 9 1/4" WITH CENTER POST. Ensure that you have a load bearing point below the center post.

Hope this helps!