How to seal hardwood floors

Two people sat on hardwood floors sealing it with paintbrushes.
(Image credit: Getty)

To ensure wooden flooring remains looking its best for years to come, it’s important to know how to seal hardwood floors. From spills and furniture scrapes, to heavy foot traffic and humid conditions, everyday life can take its toll on a wood floor, and knowing how to clean hardwood floors (opens in new tab) won’t be enough to undo this wear and tear. Instead, make sure to seal the wooden boards to protect against damage. 

Other types of flooring can be kept in good condition using the best steam mops, (opens in new tab) but when it comes to hardwood, sealing is the best way to maintain the floor’s quality and appearance. 

Why you should seal hardwood floors 

Sealing hardwood floors gives the flooring surface a protective barrier that can withstand damage from daily use. This cuts down on maintenance and will help wooden flooring last for longer.

What the expert says...

 Goodell David, Founder of WoodWorking Clarity (opens in new tab), says
“Sealing will protect your floors from water, cleaning chemicals, falling objects, and UV light.”

Older hardwood floors are often unfinished, so if you live in a period property and want to check if your floor is sealed, try placing a small drop of water onto one of the boards. If the droplet remains on the surface, the floor has been sealed. However, if the water is absorbed, the flooring is either unsealed or the sealant has worn away – and it’s time to learn how to seal hardwood floors.

How to seal hardwood floors with oil 

According to Goodell David, Founder of WoodWorking Clarity (opens in new tab), “The average lifespan of hardwood floors is about 100 years, but it won’t last that long without a sealant.” 

To seal a hardwood floor with oil;

1. Start with sanding

Sand the floor to remove any traces of other products. Use a damp cloth to remove any sanding dust or other debris.

2. Begin oiling

Starting in the corner farthest from the doorway, pour the oil onto the floor and use a rag to wipe it in the direction of the floorboards. Remove any excess with a clean cloth.

3. Re-apply and leave to dry

Apply at least two coats of oil, leaving 24 to 48 hours between application to allow for the first coat to dry.

How to seal hardwood floors with polyurethane 

When practicing how to seal hardwood floors with polyurethane, open a window to keep the room well-ventilated.

To seal hardwood floors with polyurethane;

1.  Pour the polyurethane

Decant a line of polyurethane along the wall farthest from the door, then drag a flooring applicator through the sealant and across the floor, moving from one wall to the other. Repeat to cover the entire surface, keeping the applicator on the floor to prevent bubbles.

2. Leave to dry

Allow the sealer to dry – two hours for water-based polyurethane, and 10 to 24 hours for oil-based polyurethane.

3. Re-apply if necessary

Apply up to three additional coats. Goodell David explains,  “If you notice imperfections after the first coat, you should sand then clean as usual. However, not all brands require sanding between coats.” 

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Hayley Francis

Hayley Francis is a freelance writer based in the UK with an interest in travel, culture, and the great outdoors. When not busy writing for a variety of clients, she can be found planning her next trip or hiking a new trail.

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