How to Keep Your Basement Dry Without a Dehumidifier

By: Evan Scoboria, Last updated: June 28, 2023

A damp basement can lead to many problems, including mold, mildew, and structural damage. While dehumidifiers are a popular solution for controlling basement moisture, they are not the only option. In this extensive guide, we'll explore alternative methods for keeping your basement dry without needing a dehumidifier that we use in our home and client homes.

Flower on Basement Floor

Addressing Water Issues:

Several factors can cause water intrusion, and identifying and addressing these issues is the first step toward a dry basement.

  1. Gutters and Downspouts: Gutters and downspouts help direct rainwater away from your home's foundation. If they are blocked or not functioning correctly, water can overflow and pool near your home, potentially seepage into your basement. Regularly clean your gutters and downspouts, especially in autumn when leaves can cause blockages. Also, could you ensure downspouts are aimed to direct water away from your home, ideally 5-10 feet away from the foundation? Downspout extenders can be used to achieve this distance if necessary.
  2. Grading: Grading refers to the slope of the ground around your home. Proper grading directs rainwater away from your home, preventing it from pooling around your foundation and possibly seeping into your basement. The ground should slope away from your house at least 6 inches over the first 10 feet. If your yard's slope directs water towards your home, you may need to regrade your lawn or install a French drain system to divert the water away.
  3. Foundation Cracks: Over time, it's common for a house's foundation to develop cracks. These can be entry points for water, leading to a damp basement. Please check your foundation regularly for cracks. If you find any, you can use hydraulic cement or masonry caulk to seal them. However, if gaps are significant or continue to expand, seeking professional help is essential, as this could indicate serious structural issues.
  4. Window Wells: If your basement has below-grade windows, window wells can help keep soil away from the window and provide drainage for rainwater. However, if they're not correctly installed or blocked, window wells can fill with water during heavy rain, leading to leaks into your basement. Regularly clear out debris from window wells, and consider installing window well covers to remove rainwater. If water accumulates in the wells, check the drainage system, clear any blockages, or install additional drainage if necessary.

Proper Ventilation:

Proper ventilation is an essential component of maintaining a dry and healthy basement. Here's a deeper look into various strategies for improving air circulation in your basement:

  1. Install Exhaust Fans: Exhaust fans can benefit basements with bathrooms or kitchens, where humidity levels are typically higher due to activities like cooking or showering. The fan pulls moisture-laden air out of the basement and expels it outdoors. This process helps reduce the humidity levels in the basement, preventing dampness and the growth of mold and mildew.
  2. Open Windows: If the outdoor weather permits, opening basement windows can help circulate air and reduce moisture. This method is most effective on dry, sunny days when the outdoor humidity level is lower than indoors. Fresh air can replace the humid indoor air, and the increased ventilation can help evaporate any existing moisture.
  3. Use Fans or Air Movers: Standalone fans or air movers can be placed strategically around the basement to improve airflow, especially in areas prone to dampness or with limited ventilation. They can help disperse moisture in the air, speeding up the evaporation process. Remember that fans can help with humidity but do not remove it from the basement. Therefore, using them in combination with other moisture-reducing methods is essential.

These strategies aim to maintain constant air movement in the basement, preventing the buildup of moist, stagnant air pockets that can contribute to dampness and mold growth.

Insulation and Vapor Barriers:

Vapor Barrier in Crawl Space

Insulation and vapor barriers serve as strategies to create a dry basement environment, with their functions extending beyond merely controlling temperature—they actively combat condensation and dampness. For example, basement walls and ceiling insulation can assist in sustaining a uniform basement temperature, thereby decreasing the probability of condensation that transpires when warmer, moisture-laden air interacts with the cooler surfaces in your basement.

Insulation solutions, specifically designed for basements like rigid foam board or spray foam insulation, offer moisture resistance—an attribute missing in conventional fiberglass insulation—ensuring they maintain their insulative properties even when damp. Research by the National Research Council Canada confirms the efficiency of these insulation types in managing moisture and enhancing thermal comfort in basements.

Adding to the insulative measures, a vapor barrier—an element impeding water vapor migration—can be fixed on the interior side of the basement walls and beneath its floor. This arrangement prevents moisture from permeating through the concrete and entering the basement, significantly reducing mold and mildew risks. While vapor barriers often come as plastic or foil sheets, certain specialized paints perform this function. However, it's critical to seal any potential leakage points like seams or gaps in the vapor barrier to ensure complete protection.

In numerous instances, merging insulation and a vapor barrier can offer the optimal shield against heat loss and moisture intrusion. Despite the significant reduction in moisture penetration through insulation and vapor barriers, they don't solve the water intrusion problem entirely. Significant leaks or flooding must be addressed immediately to maintain a dry and healthy basement environment.

Moisture-Resistant Building Materials:

Moisture-resistant building materials are designed to withstand damp and humid conditions, making them ideal for basements. Here's a deeper look at these materials:

  1. Moisture-Resistant Drywall: This type of drywall, also known as a greenboard or cement board, is designed to resist moisture absorption. It's often used in kitchens and bathrooms with higher humidity levels. When finishing your basement, moisture-resistant drywall can help mitigate the risk of moisture damage, as it can withstand higher humidity levels than standard drywall.

  2. Waterproof Flooring: Choosing the correct type of flooring is also crucial in a basement. Carpet, for example, can absorb moisture and become a breeding ground for mold and mildew. On the other hand, waterproof flooring options can resist water damage and are easier to dry out if water gets into the basement. Options include vinyl plank flooring, tile, and epoxy-coated concrete.

  3. Water-Resistant Paints: These paints are specially formulated to resist water and dampness, making them a good choice for basement walls. They can help prevent water seepage through the walls and resist mold and mildew growth.

  4. Pressure-Treated Wood: If you're using wood in your basement, opt for pressure-treated varieties. These woods have been treated with chemicals to resist moisture, decay, and insect damage.

  5. Mold-Resistant Insulation: Certain types of insulation, like rigid or closed-cell spray foam, are moisture-resistant and will not lose their insulative properties when wet. This can be a good option for insulating basement walls and ceilings.

Using these moisture-resistant building materials in your basement can help protect against water damage, reduce the risk of mold and mildew growth, and contribute to a healthier and more comfortable living environment. However, remember that these materials are part of a comprehensive moisture control strategy that should include proper grading, adequate drainage, and regular maintenance.

Absorbent Materials:

Desiccants or absorbent materials, such as silica gel and calcium chloride, can effectively manage humidity levels within small, enclosed spaces in your basement. For instance, silica gel—a silicon dioxide variant—excels in moisture absorption, making it an ideal solution for moisture extraction in the air. Containers of silica gel dispersed in the basement can help curtail excess moisture. A mesh cover for the containers can keep them inaccessible to pets and children, as safety is paramount.

Calcium chloride is another potent desiccant widely employed in moisture absorption products like DampRid. You can conveniently place these products, available in hanging bags or buckets, around your basement. Calcium chloride absorbs the moisture and safely transforms it into a brine within the product, preventing any spillage or leaking.

However, it's crucial to remember that these desiccants are not a panacea for severe moisture issues in a basement. They are ineffective against significant water intrusion from a faulty foundation or malfunctioning sump pump. Instead, they are effective components in a holistic moisture management approach and should not be solely relied upon.

Regular Maintenance and Monitoring:

Regular maintenance and monitoring are crucial to preventing and identifying basement moisture problems. Here's an elaboration on these concepts:

  1. Use a hygrometer: A hygrometer is an instrument that measures the amount of humidity present in the air. Regularly monitoring humidity levels with a hygrometer ensures they stay within the recommended 30-50% range. If the humidity level starts to creep up, you can take steps to reduce it before it becomes a problem.

  2. Inspect regularly: Regular inspections can help you catch signs of moisture problems early before they lead to significant damage. Look for signs of mold or mildew growth, which often appears as a fuzzy or slimy patch of black or green on walls, floors, or items stored in the basement. Also, look for water stains or discolorations on walls, floors, and ceilings, which could indicate a leak or condensation problem. Musty odors can also signal a moisture problem.

  3. Address issues promptly: If you find signs of a moisture problem during your inspections, it's essential to address them promptly. This might involve repairing a leak, improving ventilation, or using a dehumidifier or absorbent materials to reduce humidity levels. Ignoring moisture problems can lead to more significant issues, including structural damage and health problems due to mold growth.

  4. Routine maintenance: Regularly clean and maintain any appliances or systems that could contribute to moisture problems in the basement. For example, check sump pumps to ensure they are working correctly and clean gutters and downspouts regularly to prevent water from pooling near your foundation.

Maintaining and monitoring your basement regularly can prevent many moisture problems before they start, saving you time, money, and potential health issues in the long run.


While dehumidifiers are a popular solution for controlling basement moisture, several alternative methods exist for keeping your basement dry. By addressing water issues, improving ventilation, insulating and installing vapor barriers, using moisture-resistant materials, employing absorbent materials, and regularly monitoring and maintaining your basement, you can create a dry and healthy living space without relying on a dehumidifier.