Subject: Saltwater Dock
Date: Wed, 09 Apr 2003
I have a 7 year old saltwater dock of about 500 square feet. The surface had been treated with a clear stain type wood finish. The deck and rail wood is now cracked and splintering with some of the cracks about 1/4" wide. None of these cracks penetrate through the planks and the wood otherwise appears to be sound with minimal warpage. How would you recommend the deck be restored and protected from further damage?
What you are seeing is common with standard dock and deck planking. Here is
a reference on our website with a little info on it, including the cracking you
are referring to: http://www.rotdoctor.com/test/decktest/deck.html
This cracking generally goes only so far, and no farther. The wood has "adjusted"
to the local environmental conditions. It's an appearance problem, but not
a wood deterioration problem, except at the junctions of plank and joist and nails where water may become trapped. Rot can develop in these locations.
As you can see in the web reference above, we solved it with ELASTUFF 120, coated over with RHINO TOP to produce a non-skid surface. This waterproofs the deck and fills the cracks. Beyond this, the only other way you would have to treat the cracks would be with a mix of our Layup & Laminating Resin and sawdust, but this would be a fairly tedious chore. Standard wood fillers (including Bondo) would not remain in the cracks; Bondo is a polyester-based product and would pop out in a year or so.
Opaque coatings are the only real way to protect the wood, and a tough polyurethane to fill the cracks is about your only option there. You could paint the deck, but that would not really fill cracks, and it's a chore you would have to repeat about every 24 months.
Come on back if you have additional questions.