I have a partially rotted engineered wood beam 5 1/4" wide…

Can you please check your ' and " symbols. They aren't quite making sense everywhere. Any plan will necessarily NEED to extend beyond the bad section by some length (that will be determined by analysis). My proposed plan will minimize the field effort.

I'm not 100% certain until I run numbers, but my gut would have said 2'-6" on each side of the damage. I am confident I can get it to work with 2' on each side.

Thank you. I will submit the offer for you. If you accept, I will need until tomorrow evening to get through everything

This repair restores it to 100% capacity. I had to go 2'-9" on each side. 2' wouldn't work to restore the capacity to 100%. 2' would get it to about 90%.

If you view this sketch and you still feel the 2' dimension is critical (it may not be since we're going on the bottom instead of the side), then I will do an analysis of the beam to see if the full 100% strength is needed. It likely is not since LVL are often controlled by deflection and not strength.

https://www.mediafire.com/file/sz1b4c9arz42z0h/LVL_Repair.pdf/file

I see. I should have clarified that. Do you have access to the top where it's rotted?

Or to the side on both sides?

Hi Clay. I'm working on the solution with the new constraints discussed. I will have something to you today.

Given what you've described, I believe a plate on one side only can work. I'll crunch through those numbers and get you an updated sketch today.

Here is the updated repair detail.

https://www.mediafire.com/file/sz1b4c9arz42z0h/LVL_Repair.pdf/file

I thought you only had access to one side of the beam, that's why I went with lag screws. You will need access to both sides to use bolts.

I would use dimension lumber over an LVL (because they're not preservative treated and has the potential for the same issue)

I was keeping it to the 1' rotted dimension plus 2' on each side. Is the rotted section less than 1'?

That's only 16-3/4" on each side of the rotted section, correct? That's a 33% reduction on the 2'. That will be tougher to get to work. Can you get a plate on the other side that is only 4" high instead of the full height?

Ok. Let me work on the 45-1/2" plate on one side only.

Third time is a charm :-)

https://www.mediafire.com/file/sz1b4c9arz42z0h/LVL_Repair.pdf/file