How To Apply Varnish To Hardwood Floors

Follow these basic steps and learn how to apply a varnish finish coat to your hardwood floor. List of tools and materials needed included.

Floor varnish is a clear finish coat that is used to protect hardwood floors. Unlike stain, varnish does not penetrate the wood's surface; instead it forms a seal on top of the wood. An oil-based varnish is typically used for finishing hardwood floors even though water-based varnishes are gaining in popularity because of their ability to dry faster.

Varnished floors are durable and easy to clean. With normal wear and tear, varnish is resistant to moisture and wears well, but it does scratch easily and darken with age. Other drawbacks are that it is difficult to re-varnish worn spots without it being noticeable. For this reason, applying varnish to the entire floor is recommended.

Buy a good quality varnish made specifically for floors. Over time, cheap varnishes may turn odd shades of yellow or orange, instead of an amber color that complements the wood.

Applying floor varnish is a relatively easy do it yourself project. Follow these basic steps and learn how to apply a varnish finish coat to your hardwood floor.

Tools and Materials

1. Wood Filler

2. Vacuum

3. Mop

4. Tack cloth

5. Clean cotton socks

6. Clean cotton rags

7. Rubber or latex gloves

8. Oil-based Varnish - high gloss or satin finish

9. Paint thinner

10. Varnish brush (badger hair or china bristle) or Sponge pad brush

11. Extra fine sandpaper

12. #0000 Steel wool


The most important part of the varnish application process is preparing the floor properly. After removing all furniture from the room, the floor should be sanded down to the bare wood to remove all traces of old varnish. Any holes or cracks in the wood should be repaired with wood filler.

It is critical that all dust be removed from the floor and in the entire room. Vacuum the floor, walls, ceilings, lentils above doorways, tops of moldings around windows and baseboards. Next, mop the floor with a damp mop. Do not use a wet mop or the floor will need to dry out for several days.

The final step is to use a tack-cloth and wipe the entire floor, including corners and under radiators (if present) to remove all traces of dust. During this time, wear a pair of clean cotton socks when working in the room. Refrain from wearing shoes on the floor to avoid tracking in dirt or dust from other rooms.


Always read the manufacturer's instructions. Apply varnish with a badger hair paintbrush, china bristle paintbrush, or a sponge pad brush. A badger hair paintbrush will give the varnish the smoothest finish, while a sponge brush is easiest to use.

Varnish should be applied in a thin layer in the direction of the wood grain. Work in a small area, applying varnish to a few floorboards at a time. Varnish will be dry to the touch in about 12 hours and ready for a second coat in about 24 hours. Depending on temperature and humidity, varnish may take several weeks to completely dry. Apply a minimum of two coats. Applying a third coat is recommended but not necessary.

Apply varnish when temperatures between 70 and 75 degrees Fahrenheit. If the temperature falls below 65 degrees or humidity levels are high, varnish will take longer to set. Try to work on days when there is no wind. Varnish dries slowly and is tacky to the touch. Pollen or dust can easily become stuck to the floor, disrupting the smooth glassy finish you are trying to achieve.

For a smooth glassy finish with lots of depth, wipe the floor with a tack cloth after the first coat dries. Sand the floor lightly with extra fine sandpaper, then rub lightly with the #0000 steel wool. Apply the second coat of varnish. If applying a third coat, repeat the sandpaper and steel wool steps in the process before applying the third coat.


1. Pregnant women, children, and pets should be kept away from the work area.

2.Use a mask with a filter specifically for volatile substances such as varnish, and keep the room well ventilated.

© High Speed Ventures 2011