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What Kills Mold in a Crawl Space? (7 Easy Options)

What Kills Mold in a Crawl Space? (7 Easy Options)

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Are there signs of mold festering in your crawl space? If there are, you need to address this as soon as possible. Therefore, you may be asking yourself: what kills mold in a crawl space?

Several substances are effective in getting rid of mold. They include lime, vinegar, ammonia, hydrogen peroxide, baking soda, and borax. Bleach is also an effective mold-killer, but only on non-porous surfaces. Therefore, using it in a crawl space full of wood isn’t a good idea.

Read on to learn more about the substances you can use to get rid of mold in your crawl space. We’ve also outlined the main causes of mold and how to counteract them to prevent mold from developing in the first place.

How to Get Rid of Mold in a Crawl Space

Once you spot mold in your crawl space, you must address it immediately.

Here are some of the ways you can do so:

1 – Bleach

Traditionally, many homeowners and contractors have resorted to bleach as a solution for mold infestations.

This is fine as long as the surface you’re applying it on is a non-porous one. In such cases, bleach is highly effective in getting rid of mold.

The same cannot be said for porous surfaces. This is because bleach is a solution that primarily consists of water.

What ends up happening is that the chlorine in the solution kills the mold on the surface, but isn’t strong enough to seep through materials such as wood. It’s the water that goes through, and this gives the mold all the moisture it needs to fester even more.

Since your crawl space is likely to contain a lot of wood, bleach isn’t your best option when trying to address mold issues down there.

2 – Lime

Lime is a great alternative to bleach when trying to rid your crawl space of any mold. Not only is lime a more effective mold killer, but it’s also much safer for you and your family in terms of health risks.

Unlike bleach, lime doesn’t emit toxic fumes that can waft into your house and cause problems. Additionally, lime doesn’t make your house smell bad, whether from the mold or from the lime itself.

Lime kills mold by stripping it from the moisture it needs to thrive. This makes lime a great substance to prevent mold from developing in your crawl space from the get-go.

That being said, be noted that not all forms of lime are equally effective in killing mold. Your best bet is to use lime powder for this purpose.

One factor to consider is that you shouldn’t use lime near plants. However, since you’re unlikely to have plants in your crawl space, this shouldn’t be an issue.

3 – Vinegar

Another natural substance you can use to combat a mold infestation in your crawl space is vinegar, specifically white vinegar.

Although it’s not as potent a chemical as bleach, it’s also not as problematic. It may not kill mold as fast, but it’s not toxic and doesn’t pose as many health problems.

This is not to mention that vinegar is significantly cheaper than bleach.

Additionally, you can mix other chemicals such as baking soda with vinegar to boost its mold-killing power.

Just add the mixture to a spray bottle and apply it to a given surface. Then, soak the vinegar mix into the surface using a scouring brush or pad.

4 – Ammonia

If your mold situation is particularly dire, you should consider using ammonia to stem the tide.

Ammonia is a highly potent chemical that works excellently as a pesticide. Since you’ll be using it in your crawl space, the fact that it isn’t harmful to wood is a major perk.

All you need to do is spray a 2% ammonia solution onto the mold, leave it there for five minutes, scrub the area, and wash it with water.

The main concern with ammonia is its smell. This substance is notorious for its pungent odor, so make sure to not use too much.

Additionally, if you’re thinking of creating a mold-killing juggernaut by mixing ammonia and bleach, don’t. The resulting chloramine gas is highly toxic and damaging to your health.

5 – Hydrogen Peroxide

Not only is hydrogen peroxide excellent at snuffing out any mold, but it’s also a versatile sterilizing agent that kills bacteria and viruses instantly.

The way to use hydrogen peroxide as a mold killer is similar to that of ammonia. You’ll want to spray a 3% hydrogen peroxide solution on the mold-infested surface and let it rest for a few minutes. Then, use a brush to thoroughly scrub off the mold and wash the area well with water.

Make sure to have the necessary safety equipment on when using hydrogen peroxide. Gloves and a face mask are necessary if you want to avoid the harmful effects of this substance.

6 – Baking Soda

Baking soda is a substance you can use to get rid of mold in all sorts of places around the house. The crawl space is no exception.

Not only is it an excellent mold killer, but it’s also an effective cleaning agent.

All you’ll need to do is sprinkle some baking soda on the mold-infested areas of your crawl space and leave it there for 8 to 12 hours. Then, wash it off with water and wipe the area with a clean rag afterward.

7 – Borax

The final entry on our list is borax. This substance is often confused with baking soda, but they’re not the same.

Borax is sodium tetraborate, while baking soda is sodium bicarbonate.

What they do have in common is their effectiveness as mold killers.

Add one cup of borax to a gallon of warm water. Then, spray the solution onto the affected surfaces in your crawl space.

Use a clean rag to wipe off any visible mold spores. Finally, let the affected area dry while covered with the borax solution.

What Causes Mold in a Crawl Space?

There’s one main factor that allows mold to develop in your crawl space: moisture.

If you’re not careful in regulating the humidity of your crawl space, you’re likely to have persistent issues with mold.

This mold can have drastically damaging effects on the wood down there. In turn, it doesn’t bode well for your home’s structural integrity.

How to Prevent Mold in a Crawl Space

Your main consideration when trying to avoid mold in your crawl space is creating as dry an environment as possible.

There are several ways to do so.

First off, you can vent your crawl space. Venting improves airflow and allows you to expel the moist air in your crawl space to the outdoors. You can also bring the outside air into your crawl space through intake vents. However, this isn’t advised if you live in a humid area.

Additionally, you should make sure that any vents you install comply with International Residence Code (IRC) regulations.

Another way to lower your crawl space’s humidity is by hooking it up to your HVAC system.

If venting your crawl space isn’t an option for any reason, you should strongly consider putting a dehumidifier in it.

Final Thoughts

Your crawl space is right at the foundation of your house. Therefore, you need to maintain it properly. This often involves getting rid of mold that has developed down there.

So, what kills mold in a crawl space?

There are several answers to that, which include lime, vinegar, ammonia, hydrogen peroxide, baking soda, and borax.

If you use any of these highly effective mold killers, we assure you that the pesky mold plaguing your crawl space will be no match for them!

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