Varnish has been a popular choice for waterproofing outdoor wood furniture for thousands of years.
The best finish for wood in a humid, damp environment is a high-quality polyurethane or a marine-grade varnish. These finishes provide a durable, water-resistant layer that helps prevent moisture from penetrating the wood. Regular maintenance and reapplication may be necessary to maintain protection.
Ideal for woodwork including external doors, door frames, timber windows and gates, varnish provides high-performance protection against UV light and water penetration. A great choice for previously stained or treated wood, exterior varnish resists the cracking, peeling and blistering that is common to weathering.
There's a reason you've bought that front door, because you like how it looks, so why let the weather turn it grey? Our Outdoor Varnish won't change the natural colour of the wood, or yellow over time, and, because it's a varnish, it protects from whatever the weather can throw at it.
Yes, our acrylic-based varnishes are waterproof. To waterproof your project, we recommend you use two coats, waiting for the first to dry before applying the second. This is because your surface may absorb some of the varnish in the first coat and the second will ensure it is completely covered.
The most affordable way to waterproof wood is by starting with a natural wood oil and following with a coat or two of outdoor paint. Though more budget friendly in the short term, you will need to redo this method more frequently, as it is not as long lasting as, say, a pricier, high-quality sealant.
Varnish has been a popular choice for waterproofing outdoor wood furniture for thousands of years. The first mentions of varnishes described a mix of solvent and resin and were applied with a brush. Ancient cultures in Greece and Egypt used natural resins and oils to protect and beautify wood surfaces.
Massaging a generous layer of oil into the surface of your wood furniture enhances its waterproofing abilities. Wood oil can only be applied to wood furniture that has not already been sealed. It can yellow over time so it is best used for darker wood grains.
Polyurethane works better on wooden surfaces that are indoors. While varnish is durable and inexpensive, it's best suited for softer woods. Polyurethane dries quicker and requires fewer coats but won't hold up in the outdoors. You'll need to use personal protective equipment when applying both products.
Varnish. Varnishing plywood is a great way to waterproof the face and seal edges of plywood. It gives a hard, fully moisture resistant coating which has a shiny finish. Exterior wood varnishes are usually designed to expand and contract in different weather conditions, to reduce peeling and cracking.
What is the best treatment for wood outside? Roxil Coloured Wood Preserver and Roxil Wood Protection Cream is a comprehensive 2-part wood treatment that protects against wood rot, woodworm, rain and weather damage.
Polyvine Heavy Duty Extreme Varnish
For use on interior and exterior surfaces requiring an ultra-tough waterproof finish with UV protection. Polyvine Heavy Duty Varnish water-based crosslinked polyurethane with advanced resin technology brings the highest protection single pack ever developed.
Untreated Wood
You can either use a wax enriched preservative for an all-round coating or alternatively use a wax-free preserver if you want to then use a stain or a paint on top.
Polyurethane is the most durable option for indoor woodworking projects. It's highly effective at protecting cabinets, doors, furniture, and floors from scratches and abrasive damage. Polyurethane is also water-resistant and is intended to enhance the natural appearance of the wood with a satin or mid-gloss finish.
Sealant. Sealant is a popular choice for waterproofing wood, offering long-lasting protection by forming a waterproof barrier on the wood's surface. Sealant is one of the closest options for how to permanently waterproof wood. Unlike oil, sealants provide both strength and protection.
The best way to prevent rot is with proper ventilation. Condensation can gather around windows and cause rot when droplets pool and sit on the wood for a long time. Regularly open windows when cooking or use a dehumidifier to help improve air circulation and reduce condensation.
Is Polyurethane Waterproof? This finish protects your floors, but polyurethane is not waterproof. It will make your floors water-resistant, though — the coating repels water and helps prevent water absorption.
Unlike oil finishes, varnishes provide a protective film over the wood. This allows them to offer a very high level of protection and durability.
Oil-based varnish tops the durability charts in terms of water-resistance. The secret lies in its synthetic resins which have been bonded to drying oils and mixed with a thinner. (Faster to cure, varnishes that use urethane for their resin—often labeled polyurethane—dominate the modern market and are easier to find.)
Protection Against Weathering
There are two basic types of finishes used to protect wood surfaces from weathering – those that form a film or coating on the wood and those that penetrate the wood surface and leave no distinct layer. Film-forming materials include paints and varnishes.
A quality varnish can also be used to grant a tough, waterproof seal. Without such protection, moisture will absorb into the cells of the wood, causing them to swell and expand.
There are two basic product categories for waterproofing: stains and sealants. Stains are used on wood to enhance color and make them weather resistant. Sealants protect concrete and wood from moisture but do not stop water movement through the concrete from the outside. For masonry, the sealants are the go-to product.
Give the varnish a really good stir before you start. Brush it on in the direction of the wood grain, to get the best finish you'll need 2-3 coats. Make sure you leave 1 hour between each coat. Before the final coat give the wood a quick sand down.