Red Seal Carpenter Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

Varnish or polyurethane is commonly applied to protect wooden surfaces due to its ability to create a durable, water-resistant finish that safeguards the wood from moisture, wear, and other damaging elements. These finishes form a hard, protective layer on the surface of the wood, enhancing its durability while also allowing the natural beauty of the wood grain to show through.

Varnish and polyurethane are formulated to provide a long-lasting protective barrier that can withstand scratches, dents, and chemicals, making them ideal for high-traffic areas and surfaces that are frequently exposed to the elements. Moreover, they offer a variety of sheens—from matte to high gloss—allowing for customization in appearance.

While other finishes like paint, stain, and shellac have their uses, they do not provide the same level of protection against moisture and wear as varnish or polyurethane do. Paint serves more as a color coating for aesthetics, stain enhances the wood's natural color but works to penetrate rather than protect, and shellac provides a temporary finish that may not hold up as well in harsh conditions.