Most garages tend to be poorly lit, with no air conditioning, and less aerated than the rest of the house. They also have less insulation and sometimes inferior damp proofing. This gives them the perfect conditions for mold to thrive in.

Moreover, the garage door is very big and rarely forms a perfect seal when closed tight. That is an extra avenue through which mold spores can get into the garage and take root.

Couple this with wet or snow-covered car tires and the fact that people rarely clean their shoes and boots when entering the garage as they do when going into the house, and you have a room with increased chances of creating the right environment for all kinds of mold and mildew.

Signs of Mold in the Garage

Finding out if your garage has a mold infestation should be simple. Different types of mold have a wide range of signs and symptoms that are hard to miss. Here are the most popular ones

• Black, red, gray, or fuzzy white spots on the wall or ceiling. Note that mold will not grow on inorganic concrete surfaces
• The garage has a damp, musty, or dirty socks smell
• Your garage flooded recently, has a hole in the wall or a leaky roof
• Your paint seems to be peeling, is discolored, and has a powdery look

ProTip: Working in a moldy garage for hours could lead to mold exposure symptoms. The intensity varies depending on how well-aerated the garage is and the extent of the mold infestation.

Why I’m I Getting Mold in My Garage?

Before thinking of mold remediation, you should first find out why you keep getting mold in your garage.

Many homeowners have garages without mold. Here are the most notable reasons.

• Summer heat and rainy weather increase ambient humidity
• Cardboard, paper, and other moisture-wicking items are stored in the garage
• Leaking plumbing
• Wet car tires, undercarriage, and body dripping water in the garage
• Muddy or wet workboots, shoes, and other tools in the garage
• Garage doors or windows with bad weatherproofing
• Poorly built walls, especially in detached garages
• Bad drainage around the garage makes water seeps into the building.

Luckily, there’s a solution for every problem above. This will ensure that dealing with mold won’t be an annoying routine.

Note that some mold problems need professional remediation. For instance, you should call in experts if:

• You have mold patches bigger than 4 square feet
• There’s mold deep into your wood framing or drywall
• You suspect you have black mold
• You have respiratory problems and suspect cleaning the mold will exacerbate them.
• The affected surface is hard to reach

Before you jump into treating the mold, ensure that you put on some protective gear. Mold spores have harmful toxins. You want PPE gear to reduce inhalation and contact with your skin. Some of the things you should consider putting on are:

• Disposable work clothes or coveralls
• OSHA compliant respiratory face mask
• Disposable gloves and shoe covers
• Snug-fit wrap-around goggles for your eyes

The General Approach: Cleaning With Bleach

The only sure way to get rid of mold is scrubbing it off surfaces and using bleach to kill any remaining parts of the mold. 

Mix 1 cup of bleach for each gallon of water you use in the cleaning process. You can use this mix to soak non-porous surfaces. Porous surfaces are harder to treat since the mold will grow in the pores.

Let the bleach mix sit for around five minutes before you start scrubbing. You can scrub non-porous surfaces with a stiff brush using a bucket of bleach and water in the above ratios. 

Wipe the surface with a clean rag before rinsing it off again with bleach and water. Repeat until you can’t see any mold and residue stuck on the wall.

Since you can’t scrub most porous surfaces without ruining them, exercise some restraint and go for spot cleaning or scrubbing of the mold. Spray the bleach and water mix generously, letting it sit for a while before drying it off.

Dry Everything Thoroughly

After cleaning, consider setting up a couple of fans or leaving the place open for proper air circulation to dry the surfaces. Mold thrives in damp places. Keeping your walls and floors as dry as possible will kill it and prevent it from growing in the future.

Declutter and Get Rid of Mold Friendly Surfaces

It would help if you also considered decluttering your garage and getting rid of or storing mold-friendly surfaces better.

These include wood pieces, books, cardboard boxes, leather, cotton clothes, etc. Pick them off the floor and store them in well-aerated dry places within the garage.

If you don’t need others, give them away, throw them away or consider holding a garage sale. Decluttering will give you more usable space in the garage and contribute to aerating the places and reducing mold prevalence.

Deal With the Leaks and Dampness

After a thorough cleaning and decluttering, inspect the entire garage looking for sources of water that made the surfaces favorable for mold and mildew.

These could include leaking plumbing, a leaky roof, or poorly insulated walls. Find a way to keep the moisture off your garage, and you won’t have to worry about mold anymore. This stage could be technical, and hiring a building contractor could be the right way.

How to Get Rid of Mold on Concrete Floors

Cleaning mold on your concrete floor or surfaces is easy. You will need the same water and bleach blend we used before.

• Start by clearing the floor of any debris and appliances or storage you wouldn’t want wet.
• Use a power washer to clean away loose dirt, debris, and mold
• Apply the water and bleach blend and scrub away with a hard-bristle brush
• Use a pressure washer to rinse off the surface
• Open up doors and windows to air dry the place

How to Remove Mold from the Garage Ceiling

The ceiling is delicate and can’t take rough scrubbing like other concrete or drywall surfaces. You will have to spray it with an anti-fungal cleaner and let it sit for around ten minutes.

Spray it for a second time and use a soft piece of cloth to clean and dry it up. Finish it with an anti-fungal spray before leaving the garage aerated to dry up everything.

How to Prevent Mold Infestation in the Garage

After cleaning up, go the extra step to prevent your garage from getting moldy again. Here are a couple of tricks you could use to make a huge difference

• Install weatherproofing seals on the garage doors 
• Ensure you have gutters around the house and downspouts that steer water far away from the garage walls
• Deal with standing water around the house
• Install some ventilation fans to keep air moving and reduce dampness
• Store items off the floor. Install some shelves to create neat storage sections that encourage aeration
• Please get rid of cardboard boxes and replace them with plastic milk crates or plastic tubs
• Keep checking your walls for dampness or water damage and fix the problem soon
• If your ceiling is damp, chances are your roof is leaking. Have it looked into by a contractor

If the damage is too much, and you have to remodel, consider decisions that transform the garage from the traditional dingy prodigal room into a lively and likable place.

For instance, consider additional windows, some fan-driven vents, metal framing, mold-resistant building material instead of drywall, and finally, mold-resistant paint to seal everything up.

Is Mold in the Garage Dangerous?

Yes. Mold is never welcome anywhere in the house. It could cause mild to serious toxin poisoning. It will also make breathing a problem for people with respiratory issues like asthma and other allergic reactions.

What Can I Spray in the Garage for Mold?

Apart from using bleach, you could go for specific mold or anti-fungal solutions to kill and discourage mold in the garage.

Here are some products to dry out:

• Concrobium Mold Control Spray
• Star Brite Professional Grade Mold and Mildew Stain Remover
• Wet & Forget Moss, Mold, Mildew & Algae Stain Remover

Bottom Line

Frequent cleaning and decluttering of your garage can be enough to deal with mild mold. However, you will have to do more and plug in the water source if your garage walls, ceiling, or floor are visibly damp and you can’t find or fix the source.

Knowing when to DIY and when to hire a professional for thorough mold removal and damp proofing will prevent you from doing frequent and annoying cleaning that gives cosmetic satisfaction as your house rots in the background.