Homemade Concrete Sealer

Concrete is a hard-wearing and versatile flooring material that is as functional as it is aesthetically pleasing, When it is untreated and unsealed, it can be susceptible to damage or staining.

Modern interior of a living room in a house
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Concrete is a hard-wearing and versatile flooring material that is as functional as it is aesthetically pleasing.

Creating a homemade concrete sealer is fairly inexpensive to make, and is beneficial to the appearance and durability of the floor or outdoor surface.

Benefits of Sealing Concrete

There are many benefits to sealing concrete indoors or out. It improves the appearance of the floor, reduces cracking in the concrete, and makes the flooring resistant to mold and mildew. It also protects against spills from food, appliances, and vehicles. Not to mention, sealing concrete adds value to the home, as sealing driveways increases curb appeal.

Cleaning the Concrete Before Sealing

Before putting on the concrete floor sealer, you need to ensure the floor is thoroughly cleaned. It should be free of tiny dust particles, grease, oil stains or any other impurities that will cause the sealant to bubble or peel.

Mix one gallon of water and a tablespoon of mild dish soap to remove dust and dirt. For more difficult stains, a scrub sponge and degreaser can clean the area well.

Repairing Concrete Floors

After cleaning the concrete floor, inspect it for any imperfections. No matter what size the repair, make sure that the floor is smooth and even.

For small cracks, a cement caulking mix can be spread over or squeezed into the damaged area. Use a putty knife to smooth the caulk so that it is level with the floor. Allow it to dry thoroughly before applying the sealant.

Larger holes or divots require more care. Chip out the sides and bottom until they are smooth, then wipe the area clean. Brush on a concrete bonding liquid and apply freshly mixed concrete to the area.

How Homemade Concrete Sealer Works

One of the more durable and traditional concrete sealer recipes is made from linseed oil. A combination of linseed oil and paint thinner or kerosene can keep moisture at bay. It is a slow-drying liquid and was used as a masonry preservative before the advent of modern chemical sealers.

When additives such as paint thinner are added to the boiled linseed oil, it speeds up the drying time. The linseed oil isn't actually boiled. It is treated with solvents to speed up how long it takes the solution to dry.

DIY Concrete Sealer Recipe

A quality homemade sealant can be made with linseed oil and paint thinner, turpentine, mineral spirits or kerosene.

Mix the linseed oil and thinner of your choice in a 1:1 ratio in a deep bucket. Stir it gently so that you don't create bubbles. Roll it on with a paint roller or brush it on small areas. The thicker you apply the linseed oil concrete sealer, the darker the concrete will look.

Tips on Sealing Concrete

Before you roll on the homemade concrete sealer, there are a few things to know to ensure all your hard work pays off.

Work from one side of the room to an entrance. Start in a corner and roll the sealant on in small batches, overlapping as you work across the floor. Always make sure that the concrete has had enough time to thoroughly dry before adding any sealant.

If working with outdoor concrete flooring, look for a weather window of no rain or low moisture days. The concrete should have at least 48 hours to dry before the sealant can be applied. Ventilate the area where you are working well before you begin. Homemade concrete sealer can be strong and overwhelm you or anyone in the area when the fumes build in an enclosed room or outdoor area.


Kimberley McGee

Kimberley McGee

Kimberley McGee is an award-winning journalist with 20+ years of experience writing for a variety of clients, including The New York Times, Las Vegas Review-Journal Home section and other national publications. As a professional writer she has researched, interviewed sources and written about home improvement, interior design and related business trends. She earned a B.A. in Journalism from the University of Nevada, Las Vegas. Her full bio and clips can be viewed at www.vegaswriter.com.