Selecting Planking and Framing Lumber

[Charlie43]

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[MarkR]

Couple of thoughts:  

1.)  Beware of Oregon White Oak.  It is heavier, weaker and less rot resistant than Eastern White Oak.
2.)  Meranti ply may be as light as Okume as an individual panel, but usually is considerably heavier.  A 6mm Meranti panel will come in at an average weight of about 32#(28-36# by my charts).  Meranti is quite a bit more dense than Okume, but is not nearly as predictable for density.  Much cheaper, though and has superior rot resistance.  Okume is at it's best when slathered in epoxy.

[Charlie43]

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[MarkR]

Sorry for the delay in response - but I wasn't here.  I agree with most of what you said above.  

Usually, Oregon White Oak will be identified as such.  Lucky for us.  But it can never hurt to ask.

The point that I would like to make is that a glass over S&G or glass over strip construction is inherently a different structural system than traditional construction.  What these systems do is use the plywood or strips as a spacing core for a fiberglass composite structure.  It's a totally different structural system.

Something to think about:  I try not to use okoume or meranti ply without sealing.  One of the properties of this versatile wood is that the end grain wicks liquids very efficiently.  The best sealing of those end grains is epoxy resin.  If using only varnish to seal these woods, the owner must stay on top of the maintenance or the result is a temporary boat.  The first penetration of the finish will introduce water and the water will result in rot.

I have become a big fan of penetrating epoxy as a method of sealing okoume.  It uses the wicking action to draw epoxy into the wood structure to preserve it.

[Charlie43]

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[MarkR]

Well said!