Finished product. There was originally a wall there to make a small dining room behind it, but it was knocked down by the previous owner in the spirit of opening things up I presume. It left an awkwardly long living room though, and it was hard to find a good way to arrange the furniture. This solved that problem and actually makes the space feel bigger.
I bought the cheap $1.98 1x4s from Lowe's. I had to hand pick from the pile. The top choice was $5 a board but I wanted to save money. The cheap ones have rounded edges though, which wasn't the look I wanted, so I had to rip them down. Both edges, all 25 boards. I also ripped the edges off the 2x6s.
1x4s, one side with original edge, one side with ripped edge.
This is the frame made of ripped 2x6s. The ceiling joists run parallel to the new wall so I had to find one with a stud finder, and that determined the exact placement of the wall. I screwed the top one to the ceiling, then one to the floor (yes, straight into my hardwood floors), then the vertical pieces. I made the end piece go floor to ceiling because I didn't want the ends of the top and bottom pieces to show. That's probably a structural blunder but I don't think it matters here.
Because the ceiling joist determined the placement of the wall, I had to cover up an outlet, but needed one close by for the TV, so I took it out of the wall and installed it in the piece that's attached to the wall. I cut the hole a little large though. I might put a bigger outlet cover on there.
I wanted the top piece to be a full piece so I started at the top. My method was to clamp it in place from the middle, adjust the spacers, and then screw it in from the back. I moved the clamp to every place I screwed to keep it pressed tight. It was hard to hold it firmly in place otherwise.
Finished that night.