yes, they were built on site! We wanted a clean crisp look, not the rustic look of old beams.

What type of wood was used

Mahogany. We built the beams out of solid stock - 1x8's cut to be exactly 1x7 (the distance between the doors). The beams could have been made from mahogany plywood since the edges are mitered. We used the 1" strips left over as a border in the dining room floor. It looked really nice.