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Why Exterior Foundation Waterproofing is the Ultimate Home Investment

Updated on:
May 22, 2024
Why Exterior Foundation Waterproofing

Image Source: Canva

Exterior foundation waterproofing is sealing a home's foundation from the outside to prevent water intrusion and damage. Waterproofing protects against flooding, moisture, and leaks that can undermine the integrity of a foundation. This article will examine why exterior foundation waterproofing is a smart investment for homeowners looking to protect their home's most valuable asset.

We'll look at the key benefits waterproofing provides, how the process works, typical costs, optimal timing, and tips for choosing the right contractor. After reading, you'll understand why proactive exterior waterproofing is the best way for homeowners to defend their foundation and avoid expensive repairs. Investing in high-quality foundation waterproofing brings invaluable peace of mind.

Why Waterproof Your Foundation?

Waterproofing your home's foundation is one of the smartest investments a homeowner can make. There are several key reasons why exterior foundation waterproofing should be a top priority:

  • Prevent Water Damage: Water seeping into a basement or crawlspace can lead to serious moisture issues and water damage over time. Wet conditions provide the perfect breeding ground for mold, mildew, and decay. Waterproofing seals out water before it can enter your foundation.
  • Prevent Cracking and Structural Issues: When water saturates the soil around your foundation, it can cause the ground to expand and contract. This movement applies pressure on foundation walls and floors, leading to cracks and structural problems. Waterproofing relieves this pressure.
  • Create a Healthier Home Environment: Excess moisture enables mold growth, which can trigger allergies and respiratory issues. Waterproofing blocks moisture and improves indoor air quality. It also prevents musty odors.
  • Protect Home Value: Water damage, flooding, and foundation problems can seriously hurt your home's value. Waterproofing guards against expensive repairs down the road. It's an investment that pays off when selling.

Waterproofing protects against water damage, mold, cracking, and foundation structural issues. For any homeowner, it's a smart long-term investment that safeguards home value.

Benefits of Exterior Waterproofing

Exterior waterproofing is the longest-lasting method for keeping water out of a home's foundation. Unlike interior waterproofing solutions, which address symptoms like cracks and leaks from the inside, exterior waterproofing tackles the root cause of water infiltration by creating a barrier outside the foundation walls.

Some key benefits of exterior waterproofing include:

  • More Effective Protection - Since exterior waterproofing seals the outside of foundation walls, it stops water before it can enter and cause damage. This is more reliable than interior sealants, which may wear down over time.
  • Longer Lasting - High-quality exterior waterproofing systems come with 20+ year warranties. The materials are durable enough to withstand decades of weather and ground movement without fail.
  • Reduces Mold & Mildew - Keeping foundation walls dry from the outside prevents moisture accumulation inside that leads to mold growth. To further prevent mold, consider implementing strategies such as how to prevent mold on clothes in basement, ensuring a comprehensive approach to maintaining a healthier home environment.
  • Prevents Foundation Cracks - Water pressure buildup is a major cause of foundation cracks over time. Exterior waterproofing relieves this pressure and stabilizes the foundation.
  • Maintains Home Value - Water damage and foundation problems can significantly reduce a home's value. Exterior waterproofing keeps the foundation strong to maintain the home's structural integrity and value.
  • Peace of Mind - Homeowners can rest easy knowing their most valuable investment is protected from one of the biggest threats - water damage. Exterior waterproofing brings true peace of mind.

How Exterior Waterproofing Works

Exterior foundation waterproofing typically involves installing a waterproof membrane outside the foundation walls. There are several types of waterproofing membranes used:

  • Rubberized asphalt membranes - These are sheets of rubberized asphalt that adhere directly to the foundation walls. The sheets overlap each other and seal the walls from moisture.
  • HDPE (high-density polyethylene) membranes are durable plastic sheets mechanically fastened to the foundation walls with metal termination bars. The seams are sealed with mastic.
  • Bentonite clay mats - Bentonite is clay that expands when wet. The mats are unrolled along the foundation walls, where the clay can absorb moisture and expand to seal any cracks or gaps.

The process of installing exterior foundation waterproofing typically involves these steps:

  1. Excavate and expose the foundation walls. Dig out the soil 2-3 feet from the walls.
  2. Clean and prepare the foundation surface so the membrane can properly adhere.
  3. Install weeping tile and a drainage system at the base of the foundation to direct water away from the walls.
  4. Apply waterproofing primer if needed.
  5. Install the waterproofing membrane per manufacturer specifications, sealing seams, and overlaps.
  6. Secure the membrane's top edge with a termination bar.
  7. Apply a protection board over the membrane to prevent backfill damage.
  8. Backfill the excavated soil, sloping it away from the foundation.

A waterproof barrier outside the foundation walls prevents moisture from seeping into basements or crawlspaces. The drainage system redirects any collected water away from the foundation.

Image Source: Canva

Cost of Exterior Waterproofing

Exterior foundation waterproofing may seem like an expensive upfront investment, but it offers a homeowner an excellent return on investment (ROI). The average cost to waterproof a typical single-family home foundation is $3,000 to $7,000. The exact cost depends on several factors:

  • Size of foundation: Larger foundations cost more to waterproof.
  • Accessibility: Foundations with easier access drive lower costs. Difficult access adds complexity and expense.
  • Waterproofing method: Fluid-applied sealants tend to cost less than sheet membranes. Injection systems fall in the middle.
  • Additional repairs: Fixing cracks, grading, or drainage problems will increase costs.

While not cheap, proper waterproofing pays for itself over time through:

  • Prevented damage: Waterproofing stops moisture damage that ruins walls, floors, and contents. This avoids expensive repairs.
  • Higher home value: Water issues lower value. Stopping leaks raises value more than the waterproofing investment.
  • Energy savings: Preventing dampness improves insulation and reduces energy costs.
  • Healthier indoor air: Blocking moisture improves air quality and reduces mold risks.

For an average $5,000 project cost, homeowners can expect over $50,000 in avoided repairs, higher home value, energy savings, and health benefits over 20 years. That makes exterior waterproofing one of the best ROI home improvements available. The upfront cost leads to long-term savings and peace of mind.

When to Waterproof Your Foundation

Waterproofing your foundation during new construction is ideal, as you can fully protect your foundation before any damage occurs. However, existing homes can benefit greatly from exterior waterproofing, especially if you notice any water damage or leaks. Some signs that your existing foundation needs waterproofing include:

  • Cracks or openings in foundation walls
  • Mold or mildew on basement walls or floors
  • Stains on walls or floors from moisture
  • Musty smells coming from the basement
  • Leaks where walls meet floors
  • Buckling walls or floors

If you notice any warning signs, water is infiltrating your foundation and causing damage. Exterior waterproofing is highly recommended for existing homes showing signs of water damage before the problems worsen. The sooner you waterproof, the more protection you can provide for your home's structure and integrity.

While new construction is the optimal time, waterproofing an existing foundation showing damage can still provide excellent protection from further water infiltration. Consult with waterproofing contractors to inspect your foundation and recommend the best solution. Getting ahead of foundation problems as soon as possible is a smart investment in your home's health and longevity.

Choosing a Contractor

Choosing an experienced, licensed contractor you can trust is important when it comes to foundation waterproofing. Here are some tips for selecting the right company:

Check for proper licensing and insurance. Ensure the contractor is properly licensed in your state and carries liability insurance and workers' compensation. This protects you in case of any issues. Ask to see copies of their licenses and insurance certificates.

Look for expertise. Choose a company that specializes in exterior foundation waterproofing and has been in business for several years. They should be able to provide references from satisfied customers in the past. Ask how many similar waterproofing projects they complete each year.

Inquire about warranties. The contractor should offer a warranty of at least five years for materials and labor. A longer warranty (10-20 years) is even better. Make sure you understand exactly what is covered.

Choosing the right waterproofing company is crucial to getting the job done correctly. Do your research to find an experienced contractor with strong warranties and a proven track record with foundation waterproofing. This helps ensure your investment is protected in the long term.

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