Untreated wood is susceptible to natural degradation when exposed to the elements of Mother Nature. Like human skin, wood also ages when exposed to sunlight, while moisture aids in fungal growth. Whichever way you slice it, when wooden furniture exposed to these elements is left untreated, it will eventually become unusable.
So, how can this be avoided? The answer is to seal your furniture.
Sealing your favorite wooden furniture is pretty simple and there are various products to help you do it. Here are the most tried and tested waterproofing agents for outdoor wooden furniture:
- Stain and sealant
- Clear coats: polyurethane, lacquer, or varnish
- Oils: tung and linseed
This article will provide a basic overview of how to apply each product and discuss a few advantages and disadvantages. Keep reading below to learn how.
Methods of waterproofing wooden furniture
Stain and sealant
This all-in-one solution helps protect the wood from water and UV rays and can also be used to add rich color, enhancing the wood’s overall grain.
A huge advantage of all-in-one stains and sealers is that they do not darken or become yellowish over time like other products, such as polyurethane.
Instructions to apply stain and sealant
Whether your furniture is old or weathered, the process is the same. Here are the steps involved:
- Start by sanding your furniture properly to remove anything on the surface that may affect the application process. Brand new furniture will require very light sanding.
- Give the furniture a thorough wipe using wood or deck cleaner and allow it to dry completely.
- Use a high-quality natural paintbrush to apply a thin, even coat of stain and sealer to the furniture, ensuring that you do not miss any nooks and crannies.
- Leave the furniture to dry overnight.
- Apply a second coat 24 hours later.
- Do not use or place anything on the furniture for the following 24 hours.
Clear coats
Unlike oils and stains, clear coat sealers do not seep into the wood. Instead, they form a hard, shiny, protective layer on the surface, which protects against moisture and scuffs.
There are three main types of clear coat sealers:
Varnish – The most common of the clear coats, exterior varnish provides exceptional protection against water and UV rays.
The disadvantage of using varnish is that it’s extremely time-consuming compared to other products. Varnishing wood may require up to eight coats and will require to be set to dry after each coat.
Polyurethane – This is, in essence, a liquid plastic compound that creates a thin layer atop the wood, making it impervious to moisture penetration and scuffing.
The major advantage of polyurethane is that it only requires two coats compared to the eight required when using varnish. The one negative, though, is that polyurethane possesses significantly higher levels of volatile organic compounds (VOCs).
Lacquer – The main difference between lacquer and the other two clear coat products above is that it is much thinner in texture and is available in a sprayer application. However, a brush-on variety is preferred for outdoor furniture.
Lacquer provides an attractive high-gloss finish but tends to discolor over time and also possesses high VOC levels.
Instructions to apply clear coats
The application process of clear coats is very similar to stains and sealants:
- Sand your furniture thoroughly using 80 grit sandpaper.
- Give the furniture a thorough wipe using wood or deck cleaner and allow it to dry completely.
- Use a high-quality natural paint brush to apply even layers of varnish, polyurethane, or lacquer to the furniture, ensuring you don’t miss any nooks and crannies.
- Leave the furniture to dry overnight.
- Apply a second coat 24 hours later. Remember to repeat the process eight times for varnish or two to three times for lacquer or polyurethane.
- Do not use or place anything on the furniture for another 24 hours.
Oils
Natural oils such as tung and linseed oils are probably the easiest and least toxic methods of sealing wooden furniture. These natural products not only seal your wooden furniture but also penetrate it, keeping it healthier for longer.
The major drawback of natural oils is that since they do not contain large amounts of VOCs like synthetic sealers, they only provide moderate protection.
Linseed Oil
Linseed oil comes in three main variations:
Raw – Raw linseed oil provides the best look and protection after several coats, but each coat may take up to two weeks to dry completely.
Boiled – Boiled linseed oil possesses drying agents that reduce the time required between coats; however, they emit VOCs.
Polymerized – Polymerized linseed oil combines the variations above to deliver the best of both worlds. Polymerized linseed oil is made up of raw linseed oil that has been heated to allow it to thicken and, therefore, dry more quicker. This product requires just two to three days of drying between coats.
Tung Oil
Tung oil is a great option for maple and lighter woods because it does not take on a yellowish hue over time. It also creates a harder surface on the wood than linseed oil, requiring the same amount of time to dry as polymerized and boiled linseed oil.
Instructions to apply natural oils
- Sand your furniture thoroughly using 80 grit sandpaper.
- Give the furniture a thorough wipe using wood or deck cleaner and allow it to dry completely.
- Use a high-quality stiff-bristled paint brush to apply even oil distribution to the furniture, ensuring you do not miss any nooks and crannies.
- Once saturated, wipe the furniture with a clean cloth and remove excess oil.
- Leave the furniture to dry overnight.
- Apply a second or third coat if necessary, and allow each coat to dry for two to three hours.
- Do not use or place anything on the furniture for another 24 hours.
Tip: Once you are finished with your tools, such as the clothes and paintbrushes, ensure that they are cleaned in water and mineral spirits so they can be reused.
Conclusion
Providing protection from water and UV rays is essential to keeping your outdoor furniture looking great and lasting longer. This can be achieved easily using one of the common methods above and a little know-how.
Take a moment to consider your furniture’s exposure level to weather conditions and the time you have available for the application process beforehand. These answers will lead you to the most suitable option and enable you to have your furniture looking brand new all year round in no time.