Exterior Mold Removal: Prepping For Painting

Painting over mold is a temporary solution that does not address the underlying issue. Mold is a fungus that thrives in moist environments and can cause severe respiratory issues for humans and animals. Before painting, it is crucial to remove mold from the exterior of your home to ensure the paint adheres properly and lasts longer. This process involves surface preparation, which includes sanding, paint removal, and mold remediation. There are various methods for removing mold, including pressure washing and chemical treatments, but it is important to wear protective gear and choose the appropriate products to effectively eliminate mold and prevent its recurrence.

Wear safety gear, such as goggles and gloves, to protect yourself from chemicals

When removing mould from the exterior of your home, it is important to wear safety gear to protect yourself from the chemicals used in the cleaning solutions. Goggles and gloves are a must, but you may also want to consider a respirator mask.

The chemicals used to remove mould can be harsh and may cause skin and eye irritation, or more serious issues if they come into contact with your eyes or are ingested. Bleach, for example, is a common ingredient in mould removal solutions, and its corrosive properties can damage the skin and eyes. Trisodium phosphate (TSP) is another chemical that can be used, and this can also be an irritant.

Goggles will protect your eyes from any splashes of chemical solution. It is important to choose safety goggles that fit well and are resistant to chemicals. They should also have good ventilation to prevent fogging. Gloves will shield your skin from the mould removal products. Choose gloves that are thick and durable, made from materials such as rubber, nitrile, or vinyl, which will resist the chemicals.

In addition to goggles and gloves, a respirator mask is recommended when working with mould. Mould spores can be harmful if inhaled, and the mask will filter the air you breathe, reducing the risk of respiratory issues.

By taking these precautions and wearing the appropriate safety gear, you can effectively protect yourself from the chemicals used to remove mould and ensure a safe working environment.

Mix a solution of water, bleach, and trisodium phosphate (TSP) or a commercial cleaner

To remove exterior mould, you'll need to mix a solution of water, bleach, and trisodium phosphate (TSP) or a commercial cleaner. This solution will be sprayed onto the mouldy areas and scrubbed away with a brush.

Prepare the Cleaning Solution:

First, put on safety goggles and gloves to protect yourself from the chemicals. Then, in a large bucket or container, mix one gallon of warm water with one cup of bleach and 1/4 cup of trisodium phosphate (TSP). Trisodium phosphate is a chemical compound that boosts the cleaning power of the solution. If you don't have TSP, you can substitute it with a commercial cleaner or detergent.

Apply the Solution:

Pour the cleaning solution into a spray bottle. It is recommended to use a new bottle or one that has only contained plain water to prevent any chemical reactions with leftover residues.

Spray the solution generously onto the mould-affected areas. Use a stiff-bristled brush to scrub the solution into the surface, focusing on areas with visible mould. Allow the solution to sit for a few minutes to penetrate the surface and kill the mould.

Rinse and Repeat:

Rinse the cleaned area with warm water to remove the chemical residue. If there is still mould present, repeat the process as needed until the surface is free of mould.

Alternative Commercial Cleaners:

If you prefer to use a commercial cleaner, there are many disinfectant products available for scrubbing or spraying. Look for products containing bleach, but ensure they are suitable for the type of surface you are treating (e.g., porous vs. non-porous).

By following these steps and using a solution of water, bleach, and TSP or a commercial cleaner, you can effectively remove exterior mould and prepare the surface for painting.

Apply the solution to the affected area and scrub with a brush

To remove exterior mould, you'll need to apply your chosen cleaning solution to the affected area and scrub it with a brush.

First, put on safety goggles and gloves to protect your eyes and skin from the chemicals used to remove the mould.

If you're using the traditional bucket method, fill your bucket with a gallon of warm water, a cup of bleach, and a quarter-cup of trisodium phosphate (TSP). Soak your brush in this solution and begin scrubbing the affected area. If only a small portion of your home is affected by mildew, it may be more convenient to put the solution in a spray bottle and spot-clean the trouble spots.

If you're using the HYDE PivotPro™ Outdoor Cleaning Water Wand, fill its built-in mixing reservoir with an all-purpose mould and mildew cleaning solution. Adjust the dial to regulate the water-to-cleaner ratio according to the cleanser's instructions. Spray away mildew starting at the top of an exterior wall and work your way down. If you encounter stubborn mildew, use the stiff adjustable brush on the end of the wand to scrub away the mildew while dispensing the cleaning solution.

Once you've finished scrubbing, rinse the surface with a garden hose and allow it to dry.

Rinse the area with water and repeat if necessary

Rinsing the area with water is the final step in removing surface mould. It is important to use warm water for this step. The rinsing process will remove any remaining mould, as well as the cleaning solution that was used to treat the mould.

If the mould is particularly stubborn, you may need to repeat the entire mould removal process. This will involve reapplying safety goggles and gloves, mixing and applying the cleaning solution, scrubbing the area, and then rinsing the area with warm water again.

It is important to ensure that all mould is removed before painting. Mould can cause paint to bubble and peel, and it can also be a health risk for humans and animals. Inhaling mould spores can cause serious respiratory issues, such as a stuffy nose, sore throat, skin rash, wheezing, coughing, and burning eyes. Therefore, it is crucial to take the time to properly remove all mould and rinse the area thoroughly before painting.

Use a penetrating disinfectant solution like borax and vinegar to prevent mold from returning

Before painting the exterior of your home, it's important to remove any mold and mildew to ensure that the paint adheres properly and looks its best. While it's possible to simply paint over mold, this is not a long-term solution as the mold will continue to grow and reappear, causing the paint to bubble and peel.

To effectively remove mold and prevent its return, you can use a penetrating disinfectant solution like borax and vinegar. Borax is a naturally occurring mineral that not only kills mold but also stays on the surface to block its return. To make this solution, mix one cup of borax with a gallon of water, and use it to scrub the surface. You can then let it dry without rinsing. To increase the potency of the solution, you can add a cup of vinegar, which also has mold-killing properties.

By using this penetrating disinfectant solution, you can ensure that the mold is not just covered up but actually eliminated, preventing future regrowth that could spoil your paint finish. This approach is particularly useful for porous surfaces, as the solution can penetrate deeper and provide a more thorough clean.

After removing the mold, it's important to apply a primer before painting. Make sure the surface is completely dry before applying the primer, as any remaining moisture can reactivate the spores. Choose a primer that contains mildewcide and apply it liberally to provide better protection against mold.

In addition to these measures, you can also take preventative steps to inhibit mold growth. This includes cleaning your gutters regularly, as clogged gutters can cause water to run down your home's siding, promoting the growth of mold and mildew. Using an exterior paint with an anti-mildew formula can also help to prevent future mold issues.

Frequently asked questions