The wood was simply 3.5" Fir Glue-Laminated beams sanded smooth. We sealed it with a local product used mainly on log cabins, www.timberprocoatings.com. As for the connection to the wall, It was a bit more time intensive to create the seamless look. When pouring the concrete we placed 3" steel fins in the wall where the bench was placed and dadoed the beams to allow the fins to set flush on the bottom.

Feel free to look at the time-laps of the project.
http://s1310.photobucket.com/user/ericdru22/media/LinkedIn/Video/Large_zps14da846b.mp4.html?sort=3&o=0