The Spruce / Sanja Kostic
Learning how to waterproof wood will keep it beautiful, durable, and long-lasting.
you might easily waterproof wood with synthetic sealants, natural oils, or a stain/sealer.
Whichever method you choose, always work in a well-ventilated area or wear a NIOSH-approved respirator.
The Spruce / Sanja Kostic
Learn the ins and outs of how to waterproof wood using these three popular methods below.
Additional coats of sealant build the coating to the top, forming an impermeable barrier against water penetration.
Sheens range from satin to high-gloss.
The Spruce / Sanja Kostic
Oils maintain wood’s natural look and tactile quality, so you will not feel a coating.
Waterproofing oils need to be reapplied more frequently than synthetic sealantsup to twice a year.
Natural oils for waterproofing wood includelinseed oil and tung oiloil as well as Danish oil.
The Spruce / Sanja Kostic
Danish oil is a blend of tung oil and varnishes.
Oils can be brushed on or wiped on with a cloth.
They have a short re-coat time and are usually ready to be touched soon after.
The Spruce / Sanja Kostic
Stain/Sealer Combinations
Stain/sealers are exteriorwood stainsthat also contain wood sealers.
Stain/sealers can be brushed on or wiped on.
When to Waterproof Wood
All waterproofing products require the wood to be completely dry before system.
The Spruce / Sanja Kostic
Applying the coating over wet wood will trap the moisture in the wood, especially with sealants.
When waterproofing new wood, test the wood with a pin-bang out moisture meter.
Wait until the wood’s moisture content has reached 12 percent or less.
The Spruce / Sanja Kostic
Tip
Do not apply wood waterproofing products in direct sunlight.
The temperature should be between 55 to 90F, with a relative humidity level of less than 85 percent.
Mix the Sealant
Stir the sealant gently with a paint stirring stick in a separate container.
The Spruce / Sanja Kostic
Do not shake or slosh as this will create bubbles.
The re-coat waiting period for water-based polyurethane is two hours or more.
For oil-based polyurethane sealant, the re-coat time is four hours or more.
The Spruce / Sanja Kostic
Assist drying times by keeping the room warm and well-ventilated but dust-free.
Wipe clean with a tack cloth.
Apply Additional Coats and Dry
Apply two or three more coats of sealant.
The sealant should form a build on the wood, with none of the wood grain exposed.
Wait up to three days for the wood to completely dry and be ready for use.
With water-based sealant, clean tools with warm water and soap.
With oil-based sealant, clean with mineral spirits or paint thinner.
Keep the room clean and dust-free during the entire oil software process.
Dust will cling to the oil before it has fully hardened.
Sealant is the best option if you are looking to permanently waterproof wood surfaces.
Three to four coats of polyurethane are needed to waterproof wood.
Water-based polyurethane will require several more coats than oil-based polyurethane.
