Mold growth on siding is unsightly and can cause damage to your home’s exterior. Untreated mold can lead to health issues for those living in the house and surrounding areas. Fortunately, you can remove mold from siding with the right knowledge and tools. Here, we explain common causes of mold growth, effective removal techniques, and preventative measures to keep your siding mold-free in the future.
Effective Cleaning Solutions for Mold Removal
The right cleaning solution can help you successfully remove mold without damaging the siding.
Oxygen Bleach Solution
Oxygen bleach is an effective, eco-friendly option that won’t harm plants or discolor siding. Mix 1 cup of oxygen bleach powder with 1 gallon of water. Stir the mixture until the powder dissolves fully.
Vinegar and Water Solution
Mix equal parts white vinegar and water in a spray bottle for a natural alternative. You can add a bit of dish soap for extra cleaning power.
Commercial Mold Removers
Many companies specifically formulate siding mold removal products for home exteriors. Consider going with a store-bought product designed for your siding material and location. Follow the manufacturer’s instructions for the best results.
Step-by-Step Mold Removal Process
With preparations complete, it’s time to tackle the mold growth on the siding.
1. Inspect and Prepare the Area
Identify all areas of mold growth and cover nearby plants with plastic sheeting. Close windows and doors near the cleaning area.
2. Apply the Cleaning Solution
Apply the chosen cleaning solution to the affected areas using a garden sprayer. Allow the solution to penetrate the mold for 10-15 minutes.
3. Scrub and Rinse
Gently scrub the mold-covered areas with a soft-bristled brush. Then, rinse thoroughly with clean water from a garden hose. Start from the top and work downward to prevent streaking.
4. Repeat if Necessary
Repeat steps 2 and 3 for stubborn mold growth as many times as necessary to remove the mold completely.
Understanding Mold Growth on Siding
Mold thrives in damp, shaded areas with limited airflow. The following factors can contribute to significant mold growth on your siding:
Excessive moisture is the primary culprit behind mold growth on siding. Common sources of moisture on your exterior include:
- Gutter leaks or overflows
- Sprinkler systems that spray directly onto siding
- Poor drainage around the foundation
- High humidity levels
Areas of siding that receive little direct sunlight are more prone to mold growth. North-facing walls and sections shaded by trees or nearby structures are particularly vulnerable.
Accumulated dirt, pollen, and other organic debris on the siding provide food for mold spores to propagate in the presence of moisture. Clean mold off your gutters as well to prevent mold growth from spreading to your siding.
Preparing to Remove Mold from Siding
Before diving into the cleaning process, take proper precautions and gather the necessary supplies.
Working with mold can pose health risks, so the following protective gear is crucial:
- N95 respirator mask
- Rubber gloves
- Safety goggles
- Long-sleeved shirt and pants
Collect the following items for the mold removal process:
- Soft-bristled brush or sponge
- Garden sprayer or pump sprayer
- Cleaning solution
- Garden hose with spray nozzle
- Ladder, if necessary
Using Pressure Washers for Mold Removal
Pressure washers can efficiently remove mold from siding, but use caution to avoid damaging your home’s exterior.
Pros and Cons of Pressure Washing
Pressure washing lets you quickly clean large surfaces like the side of a house, making light work of what might otherwise be a labor-intensive task. The power behind pressure washing effectively addresses tough mold stains, often without further scrubbing.
Despite these advantages, pressure washing has significant downsides, especially if you do it incorrectly. The intense water jets can force water into tiny crevices in the siding, which can cause water damage or mold development within wall cavities. Some materials, such as wooden or older vinyl siding, are susceptible to warping or peeling if you do not use pressure washing carefully.
Proper Pressure Washer Techniques
Following the correct techniques can mitigate potential downsides if you decide to use a pressure washer. Use a wide-angle nozzle to carefully balance power and coverage for a broad and gentle spray that minimizes the risk of damage.
Keep the nozzle at least 12 inches from the siding surface to prevent too much direct pressure in one area, which could lead to denting or tearing. Aim the wand at a consistent angle, moving it in steady, overlapping strokes from the top of the siding downward.
Before you begin, test the spray on an inconspicuous area of your siding. That way, you can check that the settings are appropriate for your siding material without risking extensive siding damage.
Preventing Future Mold Growth
After successfully removing mold, you can take steps to prevent its return. Appropriate prevention strategies can sustain the appearance and integrity of your siding long-term, reducing the need for cleaning and repairs.
Improve Drainage and Ventilation
Improving the drainage and ventilation around your home can significantly minimize the risk of mold buildup. Clean your gutters regularly and check that they properly direct water away from the home. Inspect the surrounding area regularly for blockages, leaks, or misalignments.
Trim trees and shrubs around your home to increase airflow and sunlight. This helps reduce the shaded and damp environments where mold thrives. Consider installing additional soffit vents or upgrading your existing ones to improve airflow in and around the eaves of your home.
Regular Maintenance
Performing regular siding maintenance can pre-emptively address mold growth as well as other common issues. Schedule annual cleanings to remove dirt, grime, and organic debris from the surface.
Inspect the siding after storms or seasonal changes for cracks or other signs of wear that could allow moisture penetration. Apply a mold-resistant paint or coating to the siding to gain an extra layer of protection against future mold contamination.
Address Moisture Issues Promptly
Efficiently managing moisture both indoors and outdoors can help prevent siding mold growth. Immediately repair any leaks in your pipes, roofs, or gutter systems to avoid moisture accumulation near the siding.
Adjust your sprinkler systems so that they do not spray directly onto the house, potentially creating puddles that lead to mold growth. If necessary, install dehumidifiers in damp areas like basements and crawl spaces.
When to Seek Professional Help
While you can typically DIY mold removal for mild issues, some mold growth requires professional intervention. Extensive mold growth covering large areas of siding may be too challenging for a DIY approach. Serious mold growth often requires specialized equipment and professional-grade solutions.
You should also hire a professional to help with mold growth on upper levels or hard-to-reach areas that pose a safety risk.
Persistent mold issues that return despite DIY efforts may suggest underlying moisture problems requiring expert diagnosis and intervention. Trained mold removers have the expertise to thoroughly and efficiently address the mold at its source and recommend effective prevention methods.
