IS THERE A RULE OF THUMB, FOR THE SIZE OF TIMBERS USED IN TIMBER FRAME TRUSSES OR EVEN RAFTERS. I KNOW THERE ARE SEVERAL VARIBLES INVOLVE. IS THEIR A STRUCTUAL DESIGN ENGINEER AVIABLE THAT I CAN BE REFERED TOO. SAMPLE QUESTION:WHAT IS A SUITABLE MOISTURE LEVEL IN CYPRESS TIMBER FOR TIMBER TRUSSES? IS CYPRESS A SUITABLE MATERIAL FOR TIMBER TRUSSES? THESE ARE JUST A FEW. THANKS FOR ANY RESPONSE.

Sizing of timbers is based on lots of information.
You'll need to collect this information and have it ready when you contact a timber frame engineer.
An experienced timber frame engineer can do this, to find one, use the resource guide, select the icon on the guild home page, and follow the links to the search page, do a search and get a list of engineers for your area. They should be familiar with the requirements you'll have to meet.

Good luck,

Jim Rogers

From an engineering standpoint, cypress is a stronger wood then eastern white pine, and, I know of at least several cypress timberframes. So it seems suited well enough, depending on the size and span requirements.

Joe

im no expert in the field of timber frame engineering but i did build a 10'x12' post & beam with cypress timber from a mill in Tampa. my reason for using cypress was that it was native to SW Florida. It cut and chisled like a dream. due to the small size i think the 6"x8" were sufficient to carry the load. I would post a pic but i cant figure how.

try this
http://www.flickr.com/photos/titmas/306222803/
and this
http://www.flickr.com/photos/titmas/306222814/

here we go,