Sorry for the delay. I have been traveling the last two days.
I’d like to point out that a Professional Engineer’s standard of care typically includes a site visit to assess field conditions and get an overall understanding of the structure. This can obviously not be accomplished through the internet. The information provided here is meant for planning purposes only (general sizing and budgeting) and is based on the information provided by you. All loading cases considered are for vertical loads only, no lateral analysis has been completed. The information should be verified by a professional engineer who can visit the site to ensure that potentially important information has not been overlooked or omitted.
I can give you a couple engineered wood options for your 16’ span beam:
3-1/2” x 14” Versa-Lam 1.7 2650 SP
5-1/4” x 11-7/8” Versa-Lam 1.7 2650 SP
These are Boise Cascade products and you can go to the following link to find distributors in your area. http://www.bc.com/locations/#!/building-materials-distribution
You will need to have a local engineer detail your connections, size your support columns, determine foundation requirements, and check your structure’s lateral stability due to the fact that you are removing a large portion of wall.
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