Response to questions regarding Jim Pitts Trex deck system:
Track is Llagas Creek code 250 - nickel silver.
(to accommodate electric visitors!)
All five turnouts are number 10's.
Track center-to-center - is 7 1/2 inches
Deck width is 18 inches.
Each Trex plank is 5 1/2 inches.
Trim edge is 3 1/2 inches deep and 3/4 inches wide with outside edge
rounded.
Photographs of construction and opening day operations are posted at
http://www.southernsteamtrains.com/reference.htm
Then click link - "Elevated Track System Using Trex."
A laser level was used in construction, so track even after a year of
service and weather is flat and smooth. I prefer manual operation, so
height and level surface works well!