Dear Jane: Our company custom designs and pre-cuts a weathertight shell kit for post and beam homes, shipped to the site, to be constructed by a customer's builder on a prepared foundation. The timbers we use are dried #1 Douglas fir graded lumber (and not pictured in this photo, girders, ridge beams and purlins are southern yellow pine premium laminated beams). Our remaining material specifications can be found on our web site at http://www.postandbeam.com/package-includes. Our video is a great place to get an overview of how we work, from design to construction http://www.postandbeam.com/video-home.