Sagging garage ceiling joist

[LanceWill]

Hello all,
I'm very new. I have no construction experience, and no engineering experience.

I have a 2 car garage with inside dimensions of around 22'Wx22'D. The ceiling joists run parallel to the garage door, and the roof rafters run perpendicular. My problem is that one of my ceiling joists(2x10 or 2x12, I think) is sagging by about 1 1/2". What I see is: because the supports for the roof are all tied into one joist with no blocking, all of the weight of one side of the roof is on one joist which is causing the sag. I don't really know if that's the reason or not, it's what I'm inferring.

My plan is to jack up the joist with jack posts, and then sister in new boards along both sides of the sagging joist with bolts and construction adhesive. Since I'll be working mostly by myself, or at least with very little help, I was hoping to be able to use shorter boards (8' or 10') and just stagger the seams by 4' or so.

A) Will this work?
B) When I go to sell my house, is some inspector going to ding me for it?

Thanks,
Lance

[pushkins]

Hi Lance and welcome to the forum,

A = probably not
B = Yes.
What would be ideal is a photo of the issue, the old adage is a picture is worth a 1000 words.
The roof wouldn't be supported on any one ceiling joist or any for that matter, the roof is ultimately supported by the walls, so if you can post a picture or two it would make the job much easier.