I have a single story ranch and am doing a reno by myself as a long-term project.
Originally, the home was a small cabin and later it was expanded with addition.
The wall that I need to remove supports roof trusses which were originally part of the original cabin's roof. Left and right walls sit on the concrete perimeter foundation wall.
The span is 19ft and I am thinking about using 3×12" LVLs for this purpose (http://www.menards.com/main/storeitem.html?iid=1444438525506). I would love if someone could help me to determine if this is sufficient and I am interested in math, not in advice to hire an engineer.
Best Answer
Nope, a 2 ply 1-3/4" x 11-7/8" LVL can't span that long with this much roof on it. With a 19' span (and completely guessing on the roof span and live loading for your area) you're looking at at least a 2 ply 24" LVL or a steel beam that would be impossible to install at this point.
The best solution to open this up is to run a 3 ply 11-7/8" LVL full length but with an intermediate support in the middle making two 9.5' spans with 1 beam. The intermediate bearing post will have 18,000+ pounds on it, so you'll need a PSL or steel column.
You'll also need a new column the same size directly below it in the basement. Your existing strip footing won't be able to handle a point load that large, so you'll probably need to pour a new pad with a bunch of rebar there, and that size changes based on your soil type and conditions.
So like the other answer said, get a contractor or an engineer to help you. I'm making educated guesses on everything based on one photo and knowing you want a 19' clear span, so take that for what it's worth.