The Basics of Preparing to Paint a Floor for the General User

In this blog-post, Rawlins Paints will look at how to paint a concrete floor, as well as how to prepare wooden and metal floors for a new paint coating. As with most projects, especially involving paints, cleaners and primers, preparation is key.

The best performance from any floor paint is only achieved if the surface to be painted is correctly prepared. Always thoroughly stir any coating prior to use (i.e. 1 to 3 mins). Always apply the product to the recommended thickness using the coverage guide. Failure to do this will result in the drying time being extended and the performance of the product may be affected. The full hardness of most floor coatings is achieved over 5 – 7 days.

How To Paint A Concrete Floor

New Unpainted: Leave to cure and dry fully, normally about three months (or 1 month per inch of screed) or check moisture content is below 14%. Thoroughly remove any scale or salts (Acid Etch Solution is a good way to do this and is essential on power floated or exceptionally smooth surfaces to provide a key). Once clean, ensure surface is dry then apply the selected Floor Coating according to directions. In most instances a coat of floor primer will enhance performance.

Old Unpainted: Thoroughly clean and remove any grease or oil. This can be done with an Industrial Floor Cleaner/Degreaser. An Acid Etch solution may then be used to remove any residual scale or salts. It may be necessary to clean and roughen the surface with an industrial abrading machine where the surface has become “polished” by long term use or is smooth or granolithic. Apply the selected Floor Coating according to directions having removed all the residue of the cleaning process. Specific Floor Primers or a thinned first coat can be used to assist adhesion of most Floor Coatings to the surface in extreme cases.

Old Previously Painted: Thoroughly clean and remove any loose flaking material. Seal/Etch prime any exposed areas as appropriate and ensure the previous paint is compatible with the selected Floor Coating. The new paint must “key” to the old. This can be done by roughening the smooth surfaces or a High Performance Primer can be used as a barrier coat between old and new coatings to prevent interaction and to prime the surface. Proceed as directed on the selected Floor Coating.

How To Paint A Metal Floor

Unpainted: Thoroughly degrease and clean the surface. Prime with an appropriate metal primer ensuring compatibility with the selected Floor Coating, which should then be applied when the primer is dry.

Previously Painted: Thoroughly degrease and clean the surface, then apply a compatible primer. Test the existing paint for compatibility with the selected Floor Coating. If there is incompatibility (e.g. reaction such as blistering of the old paint etc.) then either coat with a suitable barrier coat or preferably remove all the old paint. Re-paint as with “unpainted” metal surfaces. Proceed as shown in the directions.

How To Paint A Wooden Floor

Unpainted: Thoroughly clean the surface and coat with a wood primer which is compatible with the selected Floor Coating. Proceed as shown in the directions.

Previously Painted: Thoroughly clean the surface and spot prime any exposed wood with a compatible primer for wood. Test the existing paint for compatibility with the selected Floor Coating. If there is incompatibility (e.g. reaction such as blistering of the old paint etc.) then either coat with a suitable barrier coat or preferably remove all the old paint. Take care with raised wood grain which is prone to resist wear and form hollows.

Note

Ensure good ventilation and brush or roller out to the correct film thickness. Take exceptional care to achieve this, especially on uneven surfaces to avoid ‘pooling’. Failure to do this will effect drying time and performance of the product Check the first coat is dry before applying a second. Brush-out any unavoidable ‘pools’ which have formed.

Special points to note when using 2-pack products

1. Materials used must be mixed according to instructions using a slow speed mechanical drill or special paint stirrer for at least 2 minutes. Ensure that the full perimeter and depth of the container is covered by the mixing action. This will eliminate any “soft spots” which will be caused by unmixed resins and ensure a uniform mix.
2. Primer and Topcoat coverage will vary depending on the porosity/roughness of the surface.
3. Topcoats should be brushed/rollered out to achieve the specified coverage at the correct dried film thickness. For this information consult the technical data sheets. Failure to do this will result in an inconsistent or ‘patchy” finish.
4. Ensure overcoat times specified are followed. Failure to do this may result in a subsequent system failure.
5. Temperature and humidity are critical factors when applying two pack products (water based especially). The usual temperature during application should be above 10°C and below 30°C. Excess humidity and extreme temperatures will affect the finish and can cause colour variation even in containers filled from the same batch product.
6. We recommend the same batch of a product to be used on a large area, this helps ensure a uniform finish and colour throughout.
7. Apply the product within the specified pot life.
8. Always read in full health, safety and technical information before using a product.
9. Two pack systems are chemically reactive and care should be taken when using.