Sealing will create a transparent top coat on the wood’s surface with a transparent or clean look where staining will add color or pigment.

Typically, a one-gallon container can cover between 200 and 300 square feet. This all depends on how thick the coat is, so it will probably take   about two gallons to cover a deck that is 500 square feet. Most deck sealers and deck stains are usually bought in 1-gallon containers.

Usually, it only takes about 48 hours for the wood sealer to dry assuming that the deck is in direct sunlight. Always check to make sure the   surface is totally dry before you walk on it.

Usually, you want to renew your outdoor wood sealer every year. If you used a UV-rated sealer, you will need to seal it twice a year. To see if you   need to reseal your deck, simply drop some water on the deck’s surface and see if it beads up. If it doesn’t, you need to reseal.

Giving you great protection, wood sealers have several factors that need to be considered before you buy one. Make sure it can give you the most protection against UV rays, water, and mildew. And, if you prefer natural wood products, make sure that it has the ingredients to keep your yard and loved ones protected.

There are two main types of sealers:

– Oil or solvent-based sealers

Wood treated with this type of sealer will have to be cleaned with a solvent such as thinners or mineral turpentine which gives off a very strong     odor that can take several hours to clear. Depending on the weather it will take a few days to dry or cure. Two or three coats are needed if a non-   tint sealer is used and the finished result may have slight discoloration.

– Water or acrylic-based sealers

Water-based sealers are more environmentally friendly as they have fewer VOCs (Volatile Organic Compounds). Wood treated with this type of     low VOC sealer can be washed with soap and water and it has a much quicker drying time, even when several coats are applied. A non-tint base sealer will sometimes need up to four coats for maximum protection but there will be little discoloration of the wood.

Preparation is important and depends on the existing surface of the wood. Sanding is an important preparation step as it will open the pores of   the  wood to ensure that the sealing product will penetrate and adhere to the wood. 

     – New Wood: Sanding new wood will remove any irregularities such as rough edges and splinters and ensure that the surface of the wood is   clean and smooth. Start with a rough grit of 80 – 100 progressing to a finer grit between 120 – 220. Steel wool can be used for a blemish-free   clean finish. Any crevices or nail holes will need to be filled with a wood filler and left to dry completely before sanding. Using long strokes sand the   wood  back and forth along the wood grain. To avoid scratching the surface of the wood, apply pressure lightly. If sanding by hand, use a sanding block   to ensure even distribution of pressure across the surface. Remove any trace of dust from the surface and wipe it clean before applying the sealer.

   – Previously Sealed Wood: If there are no signs of cracking or discoloration, simply remove any grime or dirt with a lint-free cloth dipped in   mineral turpentine. If there is discoloration or the treatment has worn away in sections the finish will have to be removed by deep sanding it to   reveal the raw wood underneath. 

   – Painted Wood: Remove the old paint with paint remover following the manufacturer’s instructions. Sand the surface to remove any leftover   paint and remove any sawdust with a dry cloth. Allow the surface to dry thoroughly before applying the sealer.

To ensure a successful application choose the right brush size and type. Make sure the brush is of good quality with long haired bristles that are flexible and completely dry before starting. The size of the brush will depend on the project. Window frames will typically require a 25mm brush size while doors and gates may need 50mm – 75mm. For larger areas like garage doors use a 75mm brush size or larger.

Avoid runs and spills by dipping the bristles no more than one third of the way into the sealer. As little as 2mm is enough for small or delicate work.Apply the sealer with long, even strokes along the wood grain all the way to the end of the surface to prevent runs.

Apply the sealer in thin coats, waiting until it is touch-dry before applying the next coat. Some professionals recommend a light sanding in between applications to ensure the sealer adheres properly to the previous coat. Choose a warm, dry day and avoid applying a sealer in humid, wet conditions.