How to waterproof a basement and protect against damage

If you're a homeowner with a basement, water intrusion can be a persistent nightmare. Fortunately, in the world of home improvement, there's a silver lining: waterproofing your basement. Whether you're looking to protect your valuables, create more usable living space, or simply gain peace of mind during rainy seasons, this comprehensive guide will walk you through the essential steps to keep your basement dry and your worries at bay.

In this article, we'll discuss basement waterproofing, exploring the techniques and strategies that can safeguard your underground space from water infiltration and its associated woes.

What is basement waterproofing?

Basement waterproofing is the process of sealing and fortifying the walls and foundation of a basement to prevent water intrusion and moisture-related issues. It involves a combination of techniques and materials aimed at creating a barrier that keeps water out. Typically, this includes repairing cracks in the foundation, applying waterproof coatings to walls and floors, installing drainage systems and ensuring proper grading around the exterior of the home to divert water away from the foundation.

Why you should waterproof your basement

Basement waterproofing stands as a fundamental necessity for homeowners, with its significance reaching far beyond the surface. Consider these compelling reasons to underscore why basement waterproofing should be a top priority on your homeownership checklist, as it forms a robust defense against water damage:

• Preserve house structure: Waterproofing a basement safeguards the structural integrity of your home by preventing moisture infiltration, which can weaken the foundation, lead to cracks in the walls and contribute to soil erosion around the foundation. This protective barrier also prevents the potential for mold, rot and decay, ensuring that load-bearing elements and structural supports remain strong and unaffected by moisture-related damage.
• Improve indoor air quality: Improving indoor air quality is a compelling reason to waterproof a basement because it prevents moisture-related issues, such as mold and mildew growth, which can negatively affect the air you breathe. A dry and sealed basement promotes healthier indoor air, reducing allergens and potential respiratory problems for the entire household.
• Prevent mold growth: When your basement is damp and humid, mold spores can multiply rapidly. Mold spores can cause respiratory problems and other health complications. Waterproofing keeps your basement dry and promotes a healthier living environment.
• Enhancing energy efficiency: A waterproofed basement with proper insulation can improve your home's overall energy efficiency. It reduces drafts and heat loss, resulting in lower energy bills and a more comfortable living space.
• Increasing resale value: The resale value of your home can significantly increase if you waterproof your basement, making it more appealing to potential buyers in a competitive real estate market.

How to waterproof a basement from the inside

Identifying the root cause or source of a wet basement is crucial for halting the current problem and preventing future problems from occurring. Water can enter your basement through foundation cracks, even minuscule ones, and through leaky window seals or doors. Water can also pool around your foundation if your exterior drainage is inadequate or your yard slopes, increasing pressure and allowing water to infiltrate. Once you've identified the leak, you can take action to mitigate or eliminate the risk of future water damage.

1. Clean the basement walls and floor

Initiating the waterproofing process begins with a thorough cleaning of the walls and floors, eliminating dirt and dust through a soap and water wash. It's essential to apply basement waterproofing products to a pristine surface for optimal results. If your basement is finished and contains furniture or carpeting, it's advisable to remove these items. For any upholstered furniture or carpeting that has become damp, it's prudent to consider their disposal to prevent the introduction of mold and the associated problems it can bring.

2. Remove mold if necessary

If mold is already present, perform a thorough cleaning and disinfection, and if necessary, hire a professional to remove it. It is critical to wear proper protective gear when dealing with mold, such as gloves, eyewear and a mask, especially if there is significant mold growth present. For a mold-free and healthy basement, a proactive approach is essential to mold prevention and elimination.

3. Ensure the area is dry

To ensure a consistently dry environment during basement waterproofing, take a systematic approach. Start by addressing water infiltration sources, like foundation cracks, and invest in adequate ventilation and dehumidification to reduce moisture levels, discouraging mold growth. Apply waterproofing materials and maintain them regularly. Keep the basement well-organized to promote proper air circulation. These measures collectively support a consistently dry and protected basement space throughout the waterproofing process.

4. Plug and reseal openings

Resealing and plugging basement openings are crucial to prevent moisture infiltration. Begin with a thorough inspection of doors, windows and foundation gaps, removing any old sealant. Apply high-quality sealants like silicone or polyurethane, especially around door and window frames. For larger openings, use expanding foam insulation to ensure a tight seal. This process creates a watertight barrier, preventing water intrusion and improving energy efficiency and overall waterproofing effectiveness, maintaining a dry and secure basement, protected from leaks and moisture issues.

5. Apply waterproof coating

To apply basement waterproofing coating, start by preparing a clean, debris-free surface and patching any cracks. Choose an appropriate coating material, like cement or latex-based options. Apply even coats with a brush or roller, allowing for drying intervals between layers. Inspect for missed spots and ensure adequate ventilation during curing. Properly applied, the coating acts as a moisture barrier, protecting your basement from water damage. Always follow product instructions and seek professional help for complex projects.

How to waterproof a basement from the outside

Basement waterproofing extends beyond the interior of your home and also involves taking proactive measures outdoors to prevent moisture intrusion. Exterior initiatives complement the indoor waterproofing efforts, collectively creating a robust defense against unwanted moisture in your basement.

Install gutters

Installing and maintaining gutters will implement effective water diversion away from your home as a key measure to prevent water infiltration into your basement, ensuring a dry and protected living space.

Grade the yard

Grading your yard is essential for waterproofing your basement. It involves assessing the current slope, adjusting it to direct water away from your house and maintaining the area with grass or vegetation. Proper grading diverts rainwater from your foundation, reducing the risk of water infiltration, foundation damage and mold growth. Additionally, it helps control soil erosion, preserving your landscaping and home's structural integrity.

Seal exterior foundation wall

To seal the exterior foundation walls, start by cleaning and repairing any cracks or imperfections in the foundation. Apply a waterproofing membrane or coating evenly to create a moisture-resistant barrier, allowing it to dry and cure. This process effectively prevents water infiltration and safeguards your basement from potential moisture-related issues.

What causes a wet basement?

A wet basement can be a homeowner's nightmare, and there are several common reasons why it may occur. Taking preventative measures to understand and protect yourself from these common causes is essential for homeowners seeking to prevent and address basement moisture issues:

• Overflow of groundwater: Groundwater overflow refers to the rise of the water table around a property, leading to an increased risk of water infiltration into the basement through the foundation walls or floor. This can result in basement flooding and moisture-related issues.
• Cracked foundation walls: Cracked foundation walls can be a significant concern for homeowners, as they can allow water to infiltrate the basement, potentially leading to water damage, mold growth and other structural issues.
• Poorly sealed windows and doors: Poorly sealed windows and doors refer to gaps or openings around windows and doors that are not adequately sealed to prevent air or moisture infiltration. These gaps can result from improper installation, wear and tear, aging of the seals or weatherstripping.

Waterproofing tips for preventing a wet basement

Once you’ve waterproofed your basement and taken steps on your home’s exterior to keep water away, there are a few other factors to consider.

• Install a dehumidifier to pull moisture out of the air.
• Inspect your appliances, including washer and dryer hoses, any pipes and even a dehumidifier, to avoid standing water.
• Install a drainage system in the floor by diverting water outside with a sump pump.

How much does it cost to waterproof a basement?

The cost of basement waterproofing depends on a variety of factors, including the size of the basement, the extent of damage to the floors and walls, the sources of water infiltration, potential pipe leaks, the need for grading the surrounding terrain away from the home and the installation of drainage systems inside or outside the basement. Costs for waterproofing can vary, ranging between $2,000 – $7,000, typically averaging at about $3.50 – $8 per square foot. The total expense fluctuates based on the volume of water issues in the basement and the required labor for repairs.

The bottom line

Basement waterproofing is vital to safeguard your home from water-related damage. Common causes of wet basements include groundwater overflow, cracked foundation walls and poorly sealed windows and doors. To protect against these issues, assess your basement's condition, fix any cracks or leaks promptly and ensure proper grading and drainage systems. If you're concerned about the cost, consider a cash-out refinance on your home to help finance waterproofing, ensuring a dry and secure basement and preserving the value of your property.