How To Waterproof Wood Furniture For Outdoors

Is It Necessary To Protect Wood Outdoor Furniture From Water?

If you are wondering whether it is necessary to waterproof your wooden outdoor furniture or not then the answer is yes! Wooden furniture such as tables and chairs placed outdoors need to be protected from the bad elements to make them durable.

We will explain three methods you can do to protect your outdoor furniture and make them waterproof.

Use Varnish To Protect Your Wood Furniture Against Moisture

Varnish combines drying oil, resin, and solvent that create a hard finish that can resist scratches. Varnish is flexible, doesn’t turn yellow, and also doesn’t crack when it is put under stress.

To give protection from UV Rays and moisture, use Marine varnish.

The disadvantage of using varnish as a layer of protection is that it requires a longer time to dry than any other sealant’s clear coat.

How To Apply Varnish On Your Outdoor Wood Furniture?

Follow the instructions below to apply varnish on your wood surface effectively:

  • If your wood piece is old, you must first sand the furniture. Use 80 grit level of sandpaper along with an orbital sander. The recommended size is 6 inches, but a 5-inch size is also okay.
  • Scrub your furniture using a rough brush added with deck cleaner and a water mixture with a ratio of 1:4.
  • After that, wash the cleaning solution off your furniture. Then leave it to dry properly.
  • If your furniture is new or still hasn’t had a finish, you can apply a thin varnish layer by using a paintbrush with natural bristle. Make sure to coat between the wood slats and cover the wood crevices.
  • Allow your furniture to dry completely. You can leave it overnight.
  • The next day, proceed to apply another thin varnish coat and allow it to dry to its fullest extent before you begin to apply another layer. You can do up to 8 layers of coat.
  • After applying the final coat, allow your furniture to dry for at least 24 hours.

For your information, you still need to reapply for new varnish every two or three years, depending on the condition of your furniture. Here are some good tips to make sure you achieve excellent results:

  • It is recommended to apply varnish at normal room temperature so it can dry well and get good adhesion ability.
  • Don’t shake or stir the varnish aggressively before applying it to the surface to prevent air bubbles from forming on the coated surface. Bubbles will stay visible on the surface even after the varnish has dried.

How To Waterproof Wood Furniture Using Polyurethane

Polyurethane is like plastic but in the form of liquid. Once the poly dries, it will make the surface finish dent-resistant and scratch-resistant, that’s also waterproof.

Polyurethane solution comes in 2 types. They are oil-based and water-based poly. For outdoor furniture purposes, go with the oil-based type as it can protect outdoor furniture from elements.

Otherwise, it won’t create a long-lasting waterproof ability.

The oil-based polyurethane finish has an appearance that is similar to varnish. The difference is that it doesn’t require a long time to achieve the result as it only takes two coats, while varnish requires eight coats.

There are also some health risks when applying polyurethane since the ingredients contain volatile organic compounds or VOC that are dangerous for health.

You need to be more careful when working with polyurethane and wear protective gear.

How To Apply Polyurethane To Outdoor Furniture Effectively

Follow the instructions below to apply polyurethane efficiently:

  • If you have old wooden furniture or if your furniture has another finish, you can follow steps 1 to steps 3 in the previous varnish instructions, then do the steps below.

If your furniture is still new or has no finish, you can do step number 2 below immediately.

  • Now, apply polyurethane by making a thin layer with the help of a natural bristle paintbrush.
  • Ensure you coat between the furniture slats and cover any gaps or crevices.
  • Allow your furniture to dry totally. You can leave the project overnight.
  • After the furniture dries, apply another thin polyurethane coat and allow it to dry for at least 24 hours.

Polyurethane can stay for at least 5 to 8 years, and after that, you need to reapply the poly to keep protecting your outdoor wood furniture.

Tips To Get The Best Results When Using Polyurethane

Here are some tips you can do to achieve the best results:

  • Before applying poly, place your wooden furniture at room temperature.
  • Make sure the room for your project has an adequate ventilation system.
  • Don’t shake or stir polyurethane before you apply it to your furniture to prevent air bubbles from forming.

Use Lacquer To Waterproof Wood Furniture For Outdoors

Lacquer is a tree or synthetic resin that is fused with alcohol. It is thinner than polyurethane and varnish. Thus, it can penetrate the surface deeply and has a higher protection level.

Lacquer will make the wood finish scratch-resistant with its warm tint that looks good on wood, particularly the darker mixtures.

Moreover, lacquer can dry faster than any other type of sealant. So it doesn’t require much time to apply this lacquer.

Lacquer has varieties of sheen options; once it is applied to the surface, it can be quite durable. It can last for more than 11 to 15 years if used properly.

Besides the advantages listed above, lacquer also has some disadvantages. It has high levels of VOC or Volatile Organic Compounds that can be dangerous for humans.

How To Apply Lacquer On Outdoor Furniture Effectively

  • If your wooden piece has another finish or is in old condition, you can follow steps 1 to 3 above in the varnish application section.

After that, you can do the step below. If your furniture is still brand new or has no finish, you can move to the next step below immediately.

  • Apply lacquer using a thin layer with the help of a paintbrush with natural bristle. Ensure you coat between wood slats and cover any grooves or crevices.
  • Wait for the furniture to dry for at least 2 hours.
  • After that, apply another layer of lacquer and wait another 2 hours for the coat to dry.

Lacquer will last longer than polyurethane or varnish. Thus, it will take ten years before a reapplication is required. Here are a few tips to achieve the best outcomes when working with lacquer:

  • Before applying lacquer, make sure you put your furniture in place at room temperature.
  • Provide a good ventilation system.
  • Don’t shake or stir lacquer vigorously before application.
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