The following paragraph is from TOH article on pro tips for painting exteriors. No one here in Hawaii hardware stores knows what this product is or called. Please provide brand name and product name and description so I can buy it ****** or locally. Thanks.
Hopefully, something that can be purchased at Home Depot or Lowes. Shipping is a killer here.
A Hidden Layer of Protection Makers of wooden windows and doors have a secret: Coating bare wood with a paintable water-repellent preservative keeps paint on longer. Now, Andrew D'Amato and a few other top-of-the-line painters are borrowing the trick, which is backed up by research at Purdue University and the U.S. government's Forest Products Laboratory in Madison, Wisconsin. It's important that a product's label make three claims: "water repellent," "preservative" and "paintable." The water repellent, often a wax, keeps the wood from shrinking or swelling as much when it rains, so the paint stretches less, stays intact and grips the wood longer. The preservative kills mildew, which could grow into the top paint layer and ruin its look, and fungi that cause wood to rot. There is a wide variation in formulas on the market, however. To find an effective preservative, follow the lead of the many window and door manufacturers who use products that contain 3-iodo-2-propynyl butylcarbamate, an iodine-based preservative often abbreviated IPBC.