What Should I Put On Outdoor Wood Furniture

What Should I Put On Outdoor Wood Furniture? Protecting Your Investment

Outdoor wood furniture brings a touch of natural beauty and comfort to patios, decks, and gardens. However, exposure to the elements – sun, rain, humidity, and temperature fluctuations – can quickly degrade the wood, leading to cracking, warping, fading, and rot. Therefore, selecting the appropriate finish is crucial for prolonging the lifespan of the furniture and maintaining its aesthetic appeal. The ideal product will offer protection against moisture, ultraviolet (UV) radiation, and fungal growth, while also complementing the wood's natural grain and color.

Choosing the appropriate finish requires consideration of several factors, including the type of wood, the desired aesthetic, the level of protection required, and the ease of application and maintenance. Different wood species possess varying levels of natural resistance to decay. For example, hardwoods like teak, redwood, and cedar contain natural oils and tannins that offer inherent protection, while softwoods like pine and fir are more susceptible to damage. The chosen finish should enhance the natural properties of the wood and provide additional protection tailored to its specific vulnerabilities.

This article explores the various options available for finishing outdoor wood furniture, examining the pros and cons of each to assist in making an informed decision. We'll delve into the different types of finishes, from penetrating oils to film-forming coatings, and discuss their suitability for different wood types and environmental conditions.

Understanding the Different Types of Wood Finishes

Wood finishes can be broadly categorized into two main types: penetrating finishes and film-forming finishes. Penetrating finishes, such as oils and stains, soak into the wood fibers, nourishing and protecting from within. They typically enhance the wood's natural grain and provide a soft, matte appearance. Film-forming finishes, such as varnishes and paints, create a protective layer on the surface of the wood, shielding it from the elements. They offer a wider range of aesthetic options, from glossy to satin, and can provide a more durable and longer-lasting barrier against moisture and UV radiation.

Penetrating Oils: These finishes penetrate the wood's surface, providing protection from the inside out. They are relatively easy to apply and maintain, often requiring only periodic reapplication to maintain their protective qualities. Common types of penetrating oils include:

Teak Oil: Formulated specifically for teak and other oily hardwoods, teak oil replenishes the wood's natural oils, preventing it from drying out and cracking. It provides a warm, natural look and enhances the wood's grain.
Linseed Oil: A traditional wood finish derived from flax seeds, linseed oil penetrates deeply into the wood, providing a natural, low-luster finish. Boiled linseed oil (BLO) is preferred for outdoor use as it dries faster than raw linseed oil. However, it requires regular reapplication and offers limited UV protection.
Tung Oil: Sourced from the tung tree, tung oil creates a durable, water-resistant finish that enhances the wood's natural color. It provides good protection against moisture and is often used on fine furniture. However, it can be more time-consuming to apply, requiring multiple coats and long drying times.
Decking Oils: These are formulated for exterior use, containing UV inhibitors and mildewcides. They provide good water repellency and protect the wood from sun damage. They are usually tinted which does provide additional UV protection.

Stains: Stains are designed to add color to the wood while allowing the grain to remain visible. They typically contain pigments or dyes dissolved in a solvent, such as oil or water. Stains offer limited protection on their own and should be followed by a topcoat of a clear finish to provide additional durability and weather resistance. There are two basic types of stains:

Oil-Based Stains: penetrate the wood and generally provide better water resistance and durability. They are often preferred for outdoor furniture.
Water-Based Stains: are easier to clean up and have lower VOCs (volatile organic compounds). They dry faster than oil-based stains but may require more coats to achieve the desired color.

Film-Forming Finishes: These finishes create a protective layer on the surface of the wood. They provide a barrier against moisture, UV radiation, and abrasion. They are often more durable than penetrating finishes but can be more difficult to apply and maintain. If the film is scratched or chipped, moisture can penetrate underneath, leading to blistering and peeling. Common types of film-forming finishes include:

Varnishes: offer excellent durability and water resistance. They are available in a range of sheens, from glossy to matte. Exterior varnishes typically contain UV inhibitors to protect the wood from sun damage. Spar varnish, originally developed for marine applications, is particularly well-suited for outdoor furniture due to its flexibility and resistance to cracking.
Polyurethane: A synthetic resin that forms a tough, durable film. Polyurethane is resistant to abrasion, chemicals, and water. It is available in both oil-based and water-based formulations. Oil-based polyurethanes provide better durability but have higher VOCs. Water-based polyurethanes are easier to clean up and have lower VOCs but may require more coats.
Paints: provide the most opaque finish, completely covering the wood grain. They are available in a wide range of colors and can offer excellent protection against the elements. Exterior paints are formulated to withstand sun, rain, and extreme temperatures. However, paint can be prone to chipping and peeling, especially on surfaces that expand and contract with temperature changes.
Epoxy: provides a very hard and durable finish. It’s usually used as a base layer and then covered with a spar urethane. Epoxy is nearly waterproof and prevents moisture from penetrating the wood.

Factors to Consider When Choosing a Finish

Selecting the appropriate finish for outdoor wood furniture involves considering several factors to ensure optimal protection and longevity. These factors include the type of wood, the climate, the desired aesthetic, and the level of maintenance required.

Wood Type: The type of wood is a primary consideration. Hardwoods like teak, redwood, and cedar contain natural oils and tannins that offer inherent resistance to decay. These woods benefit from penetrating oils that replenish their natural oils and enhance their grain. Softwoods like pine and fir are more susceptible to damage and require more robust protection, such as film-forming finishes or pressure treating. Pressure treating infuses the wood with chemicals that are harmful to insects and rot. It is one of the best ways to protect wood from the elements.

Climate: The climate plays a significant role in determining the appropriate finish. In areas with high humidity and rainfall, finishes that provide excellent water resistance are essential. In sunny climates, finishes with UV inhibitors are crucial to prevent fading and cracking. Coastal areas may require finishes that are resistant to salt spray. Areas with extreme temperature fluctuations demand flexible finishes that can expand and contract with the wood without cracking or peeling.

Aesthetic Preferences: The desired aesthetic is another important consideration. Penetrating oils enhance the wood's natural grain and provide a soft, matte finish. Stains allow customization of the wood's color while still allowing the grain to be visible. Film-forming finishes offer a wider range of aesthetic options, from glossy to satin, and can completely cover the wood grain with paint. The choice of finish should complement the style of the furniture and the surrounding environment.

Maintenance Requirements: The level of maintenance required is also a factor to consider. Penetrating oils typically require periodic reapplication to maintain their protective qualities. Film-forming finishes may require less frequent maintenance but can be more difficult to repair if damaged. The maintenance schedule should be realistic and sustainable, given the time and resources available.

Budget: Different finishes have different price points. Consider the overall cost of the project, including the cost of the finish, application tools, and maintenance products. While some finishes may have a higher initial cost, they may offer better durability and require less frequent maintenance, resulting in long-term savings.

Application Techniques and Best Practices

Proper application is critical to achieving optimal results with any wood finish. Careful preparation, attention to detail, and adherence to the manufacturer's instructions are essential for ensuring a durable and aesthetically pleasing finish.

Surface Preparation: The first step is to prepare the wood surface properly. This typically involves cleaning the wood to remove any dirt, grime, and mildew. Sanding the wood to create a smooth, even surface is also important. For previously finished furniture, it may be necessary to remove the old finish using a chemical stripper or by sanding. Always wear appropriate safety gear, such as gloves and a respirator, when working with chemical strippers or sanding.

Application Methods: The application method depends on the type of finish being used. Penetrating oils can be applied with a brush, cloth, or sprayer. Apply the oil liberally and allow it to soak into the wood for the recommended amount of time. Then, wipe off any excess oil with a clean cloth. Stains can be applied with a brush, cloth, or sprayer. Apply the stain evenly and wipe off any excess to achieve the desired color intensity. Film-forming finishes, such as varnishes and polyurethanes, are typically applied with a brush or sprayer. Apply thin, even coats, allowing each coat to dry completely before applying the next. Lightly sand between coats to create a smooth surface.

Drying Times: Allow the finish to dry completely before using the furniture. Drying times vary depending on the type of finish, the temperature, and the humidity. Follow the manufacturer's instructions for recommended drying times. Avoid placing furniture in direct sunlight or extreme temperatures during the drying process.

Safety Precautions: Always follow the manufacturer's safety precautions when working with wood finishes. Wear appropriate safety gear, such as gloves, a respirator, and eye protection. Work in a well-ventilated area to avoid inhaling fumes. Dispose of used rags and applicators properly, as some finishes are flammable. Store finishes in a cool, dry place away from heat and open flames.

By carefully selecting the appropriate finish and following proper application techniques, homeowners can protect their outdoor wood furniture from the elements and enjoy its beauty and comfort for years to come. Regular maintenance, such as cleaning and reapplication of the finish, will further prolong the life of the furniture and maintain its aesthetic appeal.