Weird lighting on static mesh wall

So I’m a little new to UE4, and am using the starter content to build a little room. Specifically, I’m using the 400x400 wall found in the Architecture folder of the StarterContent. I’ve created a 2x5 room with these meshes, some with windows, put a floor/ceiling in, built the lighting and this is what I get.

The lighting is very off as you can see - you can see the outline of every part of the wall where the meshes are seperate. Each wall clearly has a different brightness, and it looks very jarring. The lighting settings for the wall mesh are in the details panel. The lighting itself is kind’ve odd, because the floor and ceiling seem extremely bright, even though theres only like 4 windows. It shouldn’t be that bright.

The ceiling and floor have this issue as well, although it’s much less noticeable with the material on it. You can see it on the floor in the lower-left of the viewport, the straight line on the floor.

Do I have to build every wall out of one big mesh? Or is the startercontent wall mesh just not detailed enough to have good lighting? Or maybe, should I just stretch the mesh to fit whatever size I need? Or maybe it’s just the material used on the wall?

I’m not very good at modeling yet, so I was hoping to build some decent prototypes with the starter content meshes but ran into this issue with the lighting. I don’t want to use BSP, because I’m trying to make a level with mostly meshes as I’ve heard it’s much easier to render and will give a better framerate/loading times etc.

I figured it out myself! Just in case there are any other newbies who are having lighting issues, my solution was found in this topic on the forums:

There are many good suggestions, but the verrrry last post offered a very simple explanation and solution. Just add a skylight!