Finishing Exterior balusters

I spent an awful lot of my adult years remodeling here in South Louisiana and can say with absolute certainty that one of the greatest challenges in exterior residential work is preventing rot and decay. This may not be an issue in the Southwest but it definitely an issue here. The poor practices of exterior construction kept me busy. If I were so inclined to pursue remodeling again, I would certainly not lack for work. The beautiful plantation homes prevalent in our area are a testament to solid construction practices used 200 years ago. Sadly, many of the construction practices used on those homes are absent in modern construction.

Exterior balustrades were quite prevalent in those days. They adorned “widow’s walks”, balconies and front and rear porches. They were designed to shed water. All surfaces that could hold water were sloped down instead.

Notice that my balustrade top rail is rounded to shed water and top of the bottom rail is angled to shed water as well. The bottom of the balusters is notched to fit the top of the bottom rail. Do you see how this design minimizes the susceptibility of moisture penetration?

You will do well to remember these simple design ideas in constructing your balustrade.

Secondly:

In my remodeling experience I noticed also that rot and decay were present in exterior balustrades and exterior trim work not only because of poor design but because of the workflow in modern construction. Typically a carpenter will gather his exterior trim pieces and install them. Then the painter will come around and prime and paint the installed trim. What is wrong with this you may ask? Not all sides of trim get primed. This is especially true with exterior balusters. The bottom of the baluster is fastened to the bottom rail and though it is not facing open air, water WILL get into the end grain and percolate upward. This is where rot and decay start –from the bottom upward. The best preventative measure is to prime the underside of the baluster before installation to inhibit this percolation effect.

Lastly:

Since I am mostly using Spanish Cedar for exterior work because its inherent durability, may I give a little advice on finishing it. Spanish Cedar has a tendency to “bleed” after time and so a good OIL primer is recommended under your exterior paint. Latex primer is not a good choice for inhibiting this bleeding effect. A latex top coat can be used over the oil primer.