OK, so getting ready to start the second floor on the new workshop.

I have all the floor joists here (16″ deep wood I … 360 TJI)

I am leaving a hole in the floor to haul things up and a hole for the stair case (obviously).

On the hole, I am putting a double trimmer. According to the Weyerhaeuser software, not needed but I was going to use a double trimmer since I will use the edges to support some kind of lift (don’t want to use the roof trusses .. might pull the roof down).

Now my question … the stairs are against the wall … run parallel with the floor joists … so just leave a couple out … small landing at the top.

I again ran the software … 16″ LVL (even with a point load where the top landing ties in) …. easily handles the load … even at max conditions (100 lbs per sq ft) I am only loading it to less than 50% it’s capacity.

Then I started looking at my framing books and online.

Everyone always uses a double trimmer on the side of the steps …. why?

I can double it up if there is a good reason but don’t want spend an extra $300 if I don’t need to.

I just don’t see a reason to double it up but then I am not a builder … maybe there is a good reason?

Thanks …. Mike

PS …My wife just put up video #11 of the build …. https://www.youtube.com/watch?v=8THvQNlIycQ