Strength of Cypress
Name: Michael T. S.
Date: September 2002
I am a carpentry teacher at a prison in Texas. I was
recently at a saw mill picking up some hardwoods and was talking to the
owner. He said that their primary lumber that they milled was
Cypress. My question is, is cypress a good lumber for
construction? Does it have the strength like Fir or is it more the
rength of cedar? I guess what I am try to ask is it a good structural
lumber or should it be used for trim work?
To quote the Forest Service's Wood Handbook, cypress is, "moderately heavy,
moderately strong, and moderately hard." Shrinkage is "moderately low",
being higher than cedar but lower than Southern Pine. Its strength
properties appear to be lower than Douglas-fir, but substantially better
than most species of cedar, although lower than Port-Orford and Yellow
Cedar. Port-Orford Cedar is virtually as strong as Douglas-fir.
Cypress's traditional claim to fame is its resistance to decay, which made
it popular for caskets, tanks, doors, boat-building, and other applications
that expose the wood to cycles of wetting and drying. However, old-growth
cypress is no longer widely available except as salvage; cypress is now only
second-growth. The second-growth cypress is not as moisture resistant as
the old-growth wood, but is still used in millwork, siding, and shingles.
It is also used for interior paneling.
I assume that you are referring to Baldcypress, which is grown in the US.
Mexican cypress is somewhat more commonly used for general construction but
is not considered to be as durable as Baldcypress. I do not work with wood
much in my practice, and when I do it's mostly Southern Pine, but I would
expect that the predominant problem with using Baldcypress for structural
framing and general construction would be economic rather than engineering.
Other, stronger, less expensive lumber such as Southern Pine is widely
available and would make for more economical construction. But, if someone
will give it to you for free or at a reduced price, cypress should make a
satisfactory, though not outstanding, structural lumber.
For more detail, visit the Forest Service's Forest Products Laboratory
website at www.fpl.fs.fed.us. This site has most of their publications,
including the Wood Handbook, online.
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Update: June 2012