Before jumping into a major TF project, I want to build a tool/garden shed, approx. 10'x10' and was considering using western red cedar for a few reasons: it's cheap, and it's light enough to handle myself. Since I can't really find any references to this species in any structural engineering references or in any TF books, I thought it was either because it wasn't suitable for the typically larger timber frames, or that it wasn't suitable at all for any timber frames. I have quite a few 6x6 rough sawn cedar timbers that finished nicely to 5.5x5.5 when I ran them through my planer. My goal is to have an aestetically pleasing garden shed that looks like it fits in the Japanese landsaping rather than the cheap shed kits from Home Depot that'll probably cost me the same.

Western red cedar design values can be found in the WWPA grading rules handbook, and they are listed in the Guild Timber Frame Joinery & Design Workbook (available through this web site). The wood is just over half the strength of Doug Fir and is not suitable for tension joinery or significant bending loads.

We have worked with western red on several outdoor projects. It's weak, hard to work and damages very easily when handled rough. Maybe it's cheap for a reason?

The other problem you will have is attempting to work with 6x6's for posts. Not much room for joinery. You would be best to move up to 6x8 at least for those members.

Good luck and do your homework.