The standard roof pitch for the Charleston is a 3/12 pitch.
The typical design load allows for:
12 pounds per square foot dead load
30 pounds per square foot live load
20 pounds per square foot wind load. (Equates to 100 MPH)
There are variables that affect the design sizes of the members,
specifically the columns and the curved beams, and those variables
generally include live load conditions which are usually location
specific. Building Codes usually dictate the applicable loads to be
applied in the member size designs.
PRESSURE PRESERVATIVE TREATMENT
As noted in the component list above, if wood columns are specified,
the wood columns are fabricated with lumber pressure treated (prior
to gluing) with Penta-WR type “C” (.6 pcf [6 tenths of a pound of
preservative per cubic foot of wood] retention for “ground
contact”). For applications where the treated member is not in
ground contact, the treatment retention is .3 pcf. For the
Charleston shelter, the exterior curved beams and the fascia boards
are treated with pentachlorophenol, and the .3 pcf retention is
EnWood utilizes the pentachlorophenol treatment because of its
premier qualities and the treatment does not discolor the wood and
can be stained or painted.