Katz - Master Your Craft

Installation designs that guarantee a lasting reputation

Some LBM journal readers may be wondering why they're seeing a series of articles on installing durable exterior trim in a magazine devoted to the lumber and building material sales industry. Yes, most industry journals focus on new product information and sales strategies. But there's no better sales strategy than studying what your customer needs to know, and that applies to better building practices, too. With all the advances and changes in building material technology, dealers have become an important link in the educational chain; as building product professionals, whether your company has an installed sales program or not, the best sales strategy is knowing what your customers need to know before they need to know it themselves, so that you can support the successful growth of their businesses. And one lesson that building product professionals are perfectly positioned to teach their customers is this: We can no longer rely on tradition for training.

For instance, twenty years ago, exterior trim installation depended on old growth lumber and old-growth techniques—building methods that were passed down from one generation of carpenters to the next; The Five D's weren't even a distant concern then. But today, if a contractor installs trim without incorporating a Design that includes Deflection, Drainage, Diffusion, and a Durable Exterior Trim product, their business won't succeed.

We started this four-part series discussing and detailing how to install Waterproof Windows and Doors; next we covered Why Miters Move; afterward we advanced to Caulk-Free Columns. Now, in this article, I'll illustrate how to incorporate the Five D's into window and door trim, corner boards, and water table trim.

Non-continuous backing blocks provide air circulation behind exterior trim. Air circulation promotes diffusion, the means by which moisture vapor and liquid water are encouraged to dry. As I stated in my previous article, according to building scientists, a minimum 4 mm (3/16-in.) space is required to break the surface tension of moisture caught between cladding and drainage plane materials. Using 3/8 in. spacers, pictured here, creates an even larger ventilated rainscreen wall, a code requirement in some areas of Canada and smart construction in many areas high-rainfall areas of the U.S., especially behind any 'reservoir' cladding or finish material, like Windsor's all-wood boards and trim, and behind composite wood products or cementious siding and trim. PVC trim, like Kleer Lumber, is not a reservoir cladding and doesn't require this degree of protection.

All Exterior trim products, except for pvc, must be primed with at least two coats. Providing a primer kit for all installers is essential and easy. All that's required is a plastic container with a lid and a throw-away brush. To prevent accidental tip-over, fill the container only 1/3 of the way with primer. Cut a hole in the lid for the brush. The lid will protect fastidiously clean carpenters complaining about paint on their fingers or hands. Getting primer into every kerf, pocket-screw hole, and crevice, will ensure long-lasting reputable work.

Historic architectural building styles are gaining popularity, but installation methods lag far behind. Each detail or step in a built-up door or window cap must be designed to deflect moisture. Here, rather than installing a flat architrave molding as would occur on the interior of a home, the bead molding separating the frieze from the casing is milled with a steep slope, which diverts water quickly away from the wall trim below. Exterior trim designs executed in pvc should also include similar deflection.

Pre-assembling exterior trim packages is another way to ensure tight and long-lasting joinery. Exterior grade glues, like Titebond III (a waterproof pva adhesive) require clamping pressure in order to reach full strength. Pocket screws provide that pressure without sacrificing installation efficiency. PVC trim products can be joined with PVC cement, which creates a nearly unbreakable molecular bond—but adequate clamping pressure is still required.

Every break in the wall cladding, even sloped surfaced like this Victorian style window cap, must be properly flashed. Copper makes a beautiful flashing material. York Manufacturing will soon release a new flashing product made from a sandwich of copper and aluminum, which will cut the cost of copper flashing by more than half.

After installing cap flashing, be sure to cover it with a self-adhesive self-healing membrane, like Typar's Window Flashing. That way, all the nails driven through the siding above the trim—many of which will penetrate the up-bent flashing leg--will not defeat the value of the flashing.

Installing flashing at the top of every horizontal surface doesn't require special planning or forethought. Go ahead and install the trim right on top of the housewrap, Afterwards, cut through the housewrap along the top of the trim. Lift the housewrap and insert the flashing. Once the flashing is in place, cover it with a self-adhesive self-healing membrane.

Almost all of the techniques illustrated in this article are new to construction, just as the materials we're using today are new to construction. But one thing isn't new: low pricing doesn't build relationships; low pricing has never been the key to a successful sales program, whether you're representing building material products or installation. Only through craftsmanship and customer care can we develop real customer relationships and ensure long-term customer loyalty. Both craftsmanship and customer care begin by knowing what your customer needs and how they should be using the products you sell. And that's why you're reading how-to articles in the LBM Journal: Installation education is as important to your sales team as it is to your customers.