How to Dehumidify a Basement

Struggling with a damp, musty basement? You’re not alone—it’s a frustrating problem many homeowners face. That lingering humidity can invite mould, ruin your belongings, and even weaken your home’s structure. To make matters worse, it comes back no matter how you try to dehumidify basement levels. 

Luckily, you can take control and reclaim your basement with professional help. In this blog, we’ll discuss what’s causing dampness in your home, the ideal humidity level, and how to get rid of dampness in the basement for good. Let’s begin.

What Should the Humidity Be in a Basement?

The best humidity level for a basement is between 40% and 60%. Keeping your basement within this range helps maintain a comfortable, breathable environment and prevents issues like mould growth and respiratory diseases. 

If the humidity drops below the ideal basement humidity level, the air becomes too dry. On the other hand, when levels rise above 60%, condensation can form on surfaces, leading to mould growth, musty odours, and potential damage to your home. 

Ideally, you should measure your basement’s humidity levels regularly with a hygrometer. This will help you catch minor changes and devise corrective measures early to protect your home.

What Causes High Humidity in a Basement?

To know how to get rid of moisture in basement levels, it’s important to understand the cause. Various factors, from structural issues to environmental conditions, can contribute to the moisture buildup. Identifying these causes will help you take the right steps toward a dry and comfortable basement. Here are the main reasons why basements are humid:

Structural Cracks

Your foundation walls may develop cracks due to extreme weather conditions, soil-related issues, poor construction practices, or other stresses. These cracks may allow water to seep in, increasing the humid air in your basement. The situation gets worse after heavy rainfall or during snowmelt, leading to damp walls, floors, and air.

Faulty Sump Pump

The sump pump keeps your basement dry by removing excess water that might accumulate. If the sump pit malfunctions, whether from wear and tear, clogs, or power failure, the water that should be pumped out may gather in your basement. This creates a damp environment that worsens the humidity levels.  

Defective or Missing Gutters 

Gutters might seem like an afterthought, but they are essential for managing rainwater. If your gutters have poor drainage and are clogged, broken, or missing, rainwater has nowhere to go except down the side of your house. The water might pool around the foundation and seep into your basement. This raises the humidity levels and can damage the structural integrity of your home.

Insufficient Ventilation

Without proper air circulation, moist air can’t escape from your basement. The air becomes stagnant, and humidity levels increase, creating a breeding ground for mould. Insufficient ventilation also means stale air is trapped, making the space feel stuffy and uncomfortable.

Leaky Pipes

A small plumbing leak may appear harmless at first, but it can quickly escalate into a serious issue. Over time, the water will accumulate at the base, creating a damp environment. It can also seep into the walls and floors. This will not only encourage the growth of mould and mildew but also cause structural damage.

Poor Insulation

If your basement isn’t properly insulated, temperature differences between the inside and outside can lead to moisture buildup. Warm air from outside mixes with cooler indoor air, causing condensation on cold surfaces like walls and floors. This moisture increases humidity, creating a damp and uncomfortable environment. 

By sealing gaps and improving insulation, you can significantly reduce condensation, lowering humidity levels and creating a more comfortable, dry basement.

How to Get Rid of Moisture in Basement Levels

Now that you know what causes moisture buildup, let’s dive into practical steps on how to get rid of dampness in basement floors and protect them from further damage:

Install or Repair Your Gutter

Gutters play a vital role in keeping your basement dry. Damaged or clogged gutters can overflow, directing water toward your foundation. Ensure gutters are functional and paired with downspouts to channel water at least 4–6 feet away. Proper drainage prevents moisture from seeping into your basement walls and floors.

Fix the Plumbing System

Moisture in your basement might stem from plumbing issues. Begin by inspecting all visible pipes for leaks, drips, or rust. Look around joints and along walls where pipes run. Thereafter, check the subsurface drainage system in hidden areas like behind walls or ceilings for signs of water damage. Address any issues promptly, whether it’s sealing a small leak or replacing damaged pipes to reduce humidity in basement levels.

Repair Cracks in the Foundation

Cracks are like open doors for moisture to enter your basement. Inspect the walls and floors for visible cracks, no matter how tiny they may seem. For smaller cracks, seal them with a waterproof epoxy or concrete patching compound to prevent water seepage. 

However, if you discover larger cracks, it’s best to consult a professional. They will evaluate the structural integrity of your foundation and may recommend a range of corrective measures to restore your basement. 

Waterproof the Floor and Walls

Waterproofing your basement’s floors and walls is a crucial step in keeping moisture at bay. It ensures your basement stays dry, even in humid conditions. Here’s how to do it:

1. First, clean the surfaces to remove dirt and debris. 
2. Next, apply a waterproof sealant or coating to both the walls and floors. These products create a protective barrier, preventing water from seeping through. 
3. For added protection, install a moisture-resistant barrier such as a vapour membrane on the walls or floors. 

By waterproofing, you ensure your basement stays dry, even in the most humid conditions.

Image source: Pexels 

Warm the Basement

When the air is heated, excess moisture evaporates, reducing dampness. This prevents condensation, which often leads to musty smells and mould growth. A heat pump offers an efficient way to warm your basement and manage humidity levels.

Read more: How Heat Pumps Work

Divert Water From Your Basement

Make sure the ground surrounding your home slopes away from the basement. A proper slope directs rainwater away, preventing it from pooling around your foundation and infiltrating the basement.  

If the slope is insufficient, consider installing a proper drainage system. Additionally, you may create barriers and add downspout extensions to direct rainwater away from the foundation.

Image source: Pexels 

Install a Dehumidifier

Despite sealing leaks and improving drainage, stubborn moisture can still linger in the air, creating perfect conditions for mildew and mold growth. This is where a dehumidifier steps in to save the day. 

It actively removes excess moisture from the air, maintaining safe and ideal basement humidity levels. Select the right dehumidifier for your basement’s size, place it in moisture-prone areas, and let it do the work. Moreover, consider connecting it to drain tile systems to ensure continuous water removal without your intervention.

Read more: How To Clean & Maintain Your Humidifier

Ensure the Sump Pump Works Perfectly

If your sump pump is not working properly, water can quickly accumulate in your basement and cause flooding. 

Test it regularly to check if the pump is draining water effectively, and ensure the pump and pit are clear of debris to prevent clogs. If your sump pump is outdated or malfunctioning, replace it with the latest model. 

Get Professional HVAC Help For Your Home

Knowing how to dehumidify a basement is only the start of ensuring a dry home. Don’t let humidity take over your home and create a damp, uncomfortable environment. LG Home Comfort has the perfect solution for homeowners in Ontario! We offer same-day or next-day service and 24/7 support for emergency service calls. 

Whether you want to repair, install, or maintain your dehumidifier or a furnace, you can count on us to deliver reliable services. Our licensed and fully equipped technicians use the latest technology to provide lasting solutions, ensuring your home stays dry, comfortable, and moisture-free. 

We run exclusive offers and deals to help you save while improving your home’s comfort. We also offer same or next-day services with licensed and fully equipped technicians. Call us today for a consultation!