I don't know how anyone could tell you without a framing plan the specification for the LVL's.

What does the plan that your structural engineer designed for your alterations say about the needed support? What did the local codes office say about the plan when you filed the permit?

It's precisely this by the seat of the pants no professional involvement that gives DIYers a bad name. And it's why buyers want to see copies of the closed out permits for work done on the house during inspections. It's to keep them from buying something that will fall down around them because someone did structural work that they were unqualified to do.

For a little more info, this isn't by the seat of the pants. The structural engineer that designed these trusses and LVL's is the same one that designed the originals for the house, so they had all the existing loads, roof positions, etc.
When he added the room to the software, it almost passed with the existing two-ply 18" LVL's, without adding another LVL. Because the wall was built on the existing two LVL's, it sits higher than the floor. I am only wanting to cut two inches off to make it 16" instead of 18". I was only asking to see if someone could say, "yes, if fit barely failed and you're only removing two inches, your only reducing the load by "x", and your on 16 O.C. so your load was better distributed, etc". I should have included that it almost passed without adding the extra LVL to begin with. I'm not a typical DIYer. I ask questions, I over-engineer, and I adhere to codes. This is why I haven't proceeded.

IMHO, the only one that can (or should) answer the question is the engineer that designed it to begin with. On one hand, it sounds like he designed it to be the same depth as the existing framing; on the other, it might need to be every bit of 18". If I was the vendor for that LVL, I would void any warrantee if any modification was made AT ALL. I noticed with my engineered floor joist system that they allow a significant number of holes in the joists, and big ones, too, but that there are very tight limits on the LVL that is carrying the joists.

You know more about the situation and obviously believe removing 2 " is OK. Since we don't have any information that would allow us to contradict or support your conclusion why ask our opinion?

You need your original engineer--not us.

Good luck on your project.

Thanks, for the responses, and the input.
The engineer was kind enough to go in to work to run a few things on the software again, and even came by the house to look things over. He said cutting those LVL's either to shorten or trim, does not affect the integrity, or the warranty as long as the software approved of the specs, just a pain in the ass to rip.
Long story short is, since there were two existing 18"s and the needed 16" couldn't be run through together, he ran the numbers on 3 - 16"s and it was more than enough support with deflection being over 500+
I will be trimming the LVL down to 16, and mounting it in place tomorrow. I simply was asking whether or not it could be cut, (so i knew whether or not I would need to buy another one), and whether it drastically changes the integrity of the beam. I wasn't looking for approval, just insight. Got neither.None of you even asked questions relating to any of the project, just parenting. I involve professionals and I ask plenty of questions. Sounds like some of you answer questions with negativity by the "seats of your pants". This is probably what would make most novice DIY'ers stray away from asking questions, and just doing things. I've built many things, that are apparently still standing, and have gone behind many "Professional Contractors" to clean up their negligence and half-assness.
Sorry for the rant, but if you read all of the responses, most were just negative responses, without much insight.
For those of you that gave any insight - thanks.

Glad you did the right thing. If you go on a forum and ask a bunch of strangers (and amateurs) an engineering question, it's still your responsibility if the answer is wrong. The answer you got here was 'No', at least with the information supplied. We had no way of knowing your experience level, and it really sounded like a typical DIY 'seat-of-the-pants' solution, Sorry you were offended. In designing my own house, I learned that if there was engineering involved, I had to go to a pro, as the answers i got on various forums were all over the place. You get what you pay for.

LVL's can absolutely be ripped, much preferable to use a tablesaw; we rip them all the time to match them to existing old-house framing sizes, with the engineer's blessing of course.
The material is very hard on saw blades. I would get a thin-kerf 8 1/4" blade for your table saw and not use your good 10" blade.
Casey

@MushCreek. No worries, I was still going to get an engineer's blessing. Being the weekend, and having to wait, and wonder, really would have eaten at me. It was more of a sense of relief I was looking for. I like to learn as much as I can. Needless to say, beam is up and trusses are in place. Thanks again.

@sombreuil_mongrel Thanks. I have a Makita with a Diablo blade, and was impressed that it went through smooth. A little slow, but never stopped and didn't burn the wood. Took two inches off so that it sits lower than the existing 18's. now the floor will be even all the way to the catwalk.For anyone that comes across this, do get blessing from the engineer that sold you the beam before cutting, but know that you can cut it if they approve.

Amateurish questions are OK here. But the first rule of group problem solving is to define the problem so others can participate in the solution. When you were asked for a framing plan and specification you did not respond.

If the engineer had all of that information but put it into a computer program to give you an answer don't you think you were expecting too much from free advice on an internet forum?

I found your rant ungrateful, smug and quite annoying.