2) Determine the height of your bench.
We wanted to achieve an overall bench height of 18″ (matching the height of our kitchen chairs). Since we are adding a 3″cushion, we reduced that amount from the height of the bench, which gave us a total of 15″ for the height of the frame.
Before you secure the back side of the frame, use a level and make sure everything is straight. The goal is to make the top portion of the frame as level as possible. If your floor is uneven, you may have to play around with the height of the vertical 2″ x 4″ to compensate for the unevenness. When screwing everything into place, we made sure we secured the frame into the joists in the wall. We located them by using a stud finder.