Notice some weird discolouration on your sandstone? Yeah, that’s probably mould, mate! Dealing with mould on sandstone can be a pesky issue for many homeowners across Australia.
Not only does it spoil the natural beauty of your sandstone, but it can also pose a risk to your health if left untreated.
However, fear not, as we’ve got you covered with all the necessary information on how to safely clean mould off sandstone.
Key Points
There are 4 methods you can try to remove mould from your sandstone. These are:
With Chlorine Bleach:
- Prepare a mix of chlorine bleach and water, spray onto the mouldy sandstone, and let it sit for 10-15 minutes.
- Rinse the sandstone thoroughly with water, taking caution with dilution and gentle rinsing to avoid damage.
With Antimicrobial Spray:
- Spray the cleaner generously on mouldy areas and let it dry completely.
- Vigorously rub the entire area with an old rag soaked in the antimicrobial solution to remove the mould and prevent regrowth.
With Hydrogen Peroxide:
- Apply a 3% or 35% solution of hydrogen peroxide to a dry sandstone surface and gently scrub the affected area.
- Let the hydrogen peroxide sit for 10-15 minutes, then rinse with clean water to remove residue and remaining mould.
With Paper and Hot Water:
- Soak shredded white paper in hot water until soft, crush into a pulp-like consistency.
- Spread the paper pulp over mouldy areas, let it dry to absorb excess moisture and mould, then remove from the surface.
Why Is Mould Growing in My Sandstone?
Mould grows in sandstone because it provides a perfect environment for its growth. Sandstone is a porous material that allows moisture to seep in, creating a damp environment where mould thrives.
This moisture, combined with organic matter like leaves, dirt, or algae, acts as a food source for mould, allowing it to flourish.
Over time, mould can cause staining and damage to the sandstone, weakening its structure. To prevent mould growth on sandstone, it’s important to keep the surface clean and dry.
Regularly removing any organic matter and using a mould cleaner specifically designed for sandstone can help prevent mould from taking hold.
4 Methods You Can Try to Achieve Clean Sandstone
If you’re wondering how to get rid of mould on sandstone, here are a few options you can try.
Chlorine Bleach
If you’re dealing with mould on sandstone, pool chlorine bleach can be a solution worth trying. To use chlorine bleach effectively and safely, you’ll need to follow a few steps.
- First, prepare a mixture by combining equal parts chlorine bleach and water in a spray bottle. Make sure the solution is well-mixed.
- Next, generously spray the solution onto the affected area of the sandstone where mould has formed.
- Allow the chlorine bleach time to work, so let it sit for about 10–15 minutes. This gives it the opportunity to penetrate the mould and algae and kill them.
- After the designated time, spray the area again with the bleach solution. Then, thoroughly rinse the sandstone with water.
Because sandstone is a porous stone that is susceptible to damage from strong chemicals, it is crucial to exercise caution when using chlorine bleach on it. To prevent any harm, ensure that you properly dilute the bleach and use a gentle hose spray when rinsing.
Antimicrobial Spray
An antimicrobial spray is specifically designed to kill and prevent the growth of mould and other harmful microbes on natural stone surfaces like sandstone pavers or sandstone paving. You can easily find an antimicrobial spray at your local hardware store.
Here are some simple steps on how to use the antimicrobial spray,
- Spray the cleaner generously on the mouldy sections of your sandstone surface. If the affected area is large, you can even rent a fogger to ensure complete coverage.
- After applying the spray, allow it to dry completely.
- Once the spray has dried, take an old rag and vigorously rub the entire area to remove the mould. If you soak the rag in the same antimicrobial solution, it will help prevent any regrowth.
- Make sure to cover the entire affected area with the solution to ensure a thorough cleaning.
Hydrogen Peroxide
You can also consider using hydrogen peroxide as a solution to remove mould from your sandstone tiles and other surfaces.
A 3% hydrogen peroxide solution is suitable for general cleaning purposes. If the mould proves to be stubborn, you can try using a 35% solution instead.
To get started, follow these simple steps
- Put on gloves to protect your hands from the hydrogen peroxide.
- Make sure the affected sandstone is dry. If there is any standing water or excessive moisture on the surface, try to remove it with a towel or let it dry naturally.
- Pour a small amount of hydrogen peroxide onto a clean cloth or sponge. You can also use a spray bottle to apply the hydrogen peroxide, but be careful not to oversaturate the sandstone.
- Gently scrub the area affected by the mould with the hydrogen peroxide-soaked cloth or sponge. Apply slight pressure and make sure to cover the entire mould-infested area.
- Let the hydrogen peroxide sit on the sandstone for about 10-15 minutes to allow it to penetrate and kill the mould spores.
- Rinse the sandstone with clean water to remove any residue and remaining mould.
Hydrogen peroxide is a powerful oxidising agent that effectively kills mould and removes stains without causing damage to your sandstone.
However, it’s always important to follow safety precautions and test a small, inconspicuous area before cleaning larger surfaces.
Paper and hot water
You can also try using just paper and hot water to remove that pesky mould and have your sandstone looking as good as new.
Here’s how it works:
- Start by shredding some white paper into small pieces.
- Then, place the paper in a container filled with hot water and let it soak until it becomes soft. Once the paper is nice and soft, crush it to create a pulp-like consistency.
- Take this paper pulp and spread it over the mouldy areas on your sandstone. Make sure to cover all the affected spots. The moisture from the pulp will seep into the stone, helping to loosen the mould and make it easier to remove.
- As the paper dries, it will absorb the excess moisture from the sandstone and also the mould itself. This process may take some time, so be patient.
- Once the paper is completely dry, you can simply remove it, along with the mould, from the surface of your sandstone.
How To Keep Mould Off Your Sandstone Pavers and Other Sandstone Surfaces
If you want to prevent mould from returning to your sandstone, there are a few things you need to do in order to accomplish that:
Regular cleaning
Regular cleaning helps remove any dirt, debris, or organic matter that can promote mould growth. You can do routine cleaning on your sandstone surfaces with warm water and a mild detergent. Use a soft brush or broom to prevent damaging the sandstone.
Proper drainage
Ensure that your sandstone surfaces have proper drainage mechanisms in place. Good drainage prevents water from pooling or stagnating on the sandstone, thus reducing moisture levels and mould growth.
Seal the sandstone
Consider sealing your sandstone surfaces with a mould-resistant sealant. This can create a protective barrier, making it harder for mould to grow on the stone. Consult a professional for advice on suitable sealing products for your sandstone type.
Sun exposure
Expose your sandstone to sunlight whenever possible. Sunlight helps to dry out the stone and inhibit mould growth. Trim back any overhanging vegetation that may shade the sandstone and reduce sun exposure.
Adequate ventilation
Provide proper airflow and ventilation to the sandstone areas. Good air circulation can help prevent excess moisture buildup, which is conducive to mould growth. Use fans or open windows and doors to improve ventilation.
Control humidity
Maintaining optimum humidity levels is crucial in mould prevention. Use dehumidifiers in indoor areas to reduce moisture levels, especially in damp or humid environments such as basements or bathrooms.
Regular inspection
Monitor your sandstone surfaces regularly for any signs of mould growth or water damage. Early detection allows swift action and prevents mould from spreading further.
Promptly address water leaks
Address any leaks or water-related issues immediately. Fix leaky pipes, repair damaged roofing, and ensure proper waterproofing to avoid excess moisture exposure to your sandstone.
Avoid harsh chemicals
When cleaning sandstone, avoid using harsh chemicals, bleach, or acidic cleaners. These can damage the stone and strip away the protective sealant, making it more susceptible to mould growth.
How Stone Protection Can Help You Remove Mould Off Sandstone
If the mould on your sandstone just wouldn’t let go of its rent-free life, then perhaps it’s time to call the professionals to conduct the eviction.
Stone Protection is here to help you remove mould from your sandstone and keep it that way. Our team of professionals have the expertise and the tools to properly assess the state of your sandstone and conduct the best mould removal methods.
Frequently Asked Questions
Does pressure washing help in removing mould from sandstone?
Yes, pressure washing can effectively remove mould from sandstone surfaces.
How do you power wash sandstone?
When power washing sandstone, use low-pressure settings and a wide-angle nozzle to avoid causing damage. Keep the nozzle at a safe distance from the surface.
How do you clean sandstone without damaging it?
To clean sandstone without causing damage, use a soft brush or cloth with a mild detergent and water. Avoid using harsh chemicals or abrasive cleaners.
Does vinegar damage sandstone?
Vinegar can potentially damage sandstone, as its acidic properties may cause erosion and discolouration over time.
How do you get black stains out of sandstone?
Black stains on sandstone can be removed by using a mixture of water and bleach, or a specialised stone cleaner. Scrub gently and rinse thoroughly.
Why is my sandstone turning black?
Sandstone can turn black due to a variety of reasons, such as organic growth, pollution, or moisture accumulation. Proper cleaning and maintenance can help prevent this.
What damages sandstone?
Various factors can damage sandstone, including harsh weather conditions, acidic substances, improper cleaning methods, and lack of maintenance. It is important to handle sandstone with care to preserve its integrity.
