Thoroseal is a building product manufactured by BASF Construction Chemicals. It is a waterproof cement-based coating that is used to fill, seal and protect interior and exterior surfaces. It is resistant against weather erosion and can be used to protect concrete, brick, building blocks and other materials. The application of Thoroseal is carried out in a similar way to painting.
Things You'll Need
High-pressure water spray
Power mixer fitted with mixing paddle
Tampico fiber brush
Fill up the container of your high-pressure water spray with water. Use the spray to blast all the dirt, dust and other contaminants from the surface to which Thoroseal will be applied. Make sure the surface is completely clean before you apply Thoroseal.
Use a bucket and a power mixer fitted with a mixing paddle to mix the Thoroseal with water. Thoroseal can be mixed by hand, but using a power mixer is more effective. Mix the Thoroseal with water at a ratio of 6 to 8 quarts of water for a 50-lb. bag of Thoroseal.
Mix the Thoroseal with water until the consistency of the mixture is smooth and thick. Be sure to work any lumps out of the mixture.
Leave the Thoroseal mixture for at least ten minutes before you apply it to the desired surface. This allows the water to fully absorb into the powder.
Dampen the surface you want to apply Thoroseal to with water before application. This prevents drag when you apply the Thoroseal.
Use a tampico fiber brush to apply the Thoroseal to the desired surface. Thoroughly brush the Thoroseal over the entire surface and make sure the surface is covered evenly. Aim for 2 lbs. of Thoroseal mixture for every square yard of the surface.
Finish the coating with smooth horizontal strokes over the entire surface. Leave the coating for 24 hours to cure before applying the second coat.
Mix more Thoroseal and water as before, and apply it to the already covered surface. This coat should be half the thickness of the first coat. Try to apply 1 lb. of Thoroseal mixture for every square yard of the surface.
Use an acrylic, polymer emulsion additive when mixing the Thoroseal with water to improve the coating's effectiveness.
Do not apply Thoroseal to already painted surfaces.