How to Waterproof a Second-Floor Balcony and Deck: Expert Insights from Rock Solid Waterproofing

Feb 5, 2025 | Waterproofing

Water damage is a silent threat that can compromise the integrity of outdoor living spaces, especially on elevated structures such as second-floor balconies and decks. Whether you’re a homeowner in Portland, OR, Vancouver, WA, or anywhere with frequent rainfall, protecting these areas is crucial for maintaining long-term structural soundness and aesthetic appeal. In this post, we’ll explore tried-and-true methods of waterproofing second-floor balconies, evaluate the longevity of rubber deck coatings, and discuss whether staining or waterproofing is the best choice for your deck. Drawing on insights from Ken VahnDijk—owner of Rock Solid Waterproofing—this guide offers practical knowledge to help you make informed decisions about safeguarding your home.

Table of Contents

  1. Understanding the Importance of Waterproofing
  2. The Second-Floor Balcony Challenge
  3. Effective Waterproofing Systems: A Look at Westcoat
  4. How Long Will Rubber Deck Waterproofing Last?
  5. Is It Better to Stain or Waterproof a Deck?
  6. Preparing for a Waterproofing Project
  7. Maintenance Tips for Longevity
  8. The Value of Professional Expertise
  9. Frequently Asked Questions
  10. Conclusion

1. Understanding the Importance of Waterproofing

Waterproofing is more than just a cosmetic choice—it’s a vital aspect of home maintenance that protects structural integrity. When moisture penetrates the surface of a balcony or deck, it can travel into wooden support beams, weaken metal connectors, and encourage mold or mildew growth. Over time, these issues lead to costly repairs or even structural failure. In the rainy Pacific Northwest, where mold and humidity are common culprits, the risk is even higher.

1.1 The Risks of Ignoring Waterproofing

  • Rot and Decay: Wood is highly susceptible to rot if exposed to prolonged moisture. Even treated or sealed wood can eventually degrade without proper protection.
  • Mold and Mildew: Damp environments foster the growth of mold spores, which can negatively impact both the appearance of your deck and the air quality in surrounding living spaces.
  • Structural Weakenings: Metal connectors, nails, and screws can rust or corrode when exposed to water. This compromises the overall stability of the deck or balcony.
  • Costly Repairs: Addressing advanced water damage typically requires partial demolition, replacement of structural elements, and more comprehensive waterproofing—leading to higher expenditures.

2. The Second-Floor Balcony Challenge

Second-floor balconies bring an elevated sense of style and functionality to a home. Yet, their height and exposure make them especially vulnerable to water damage. According to Ken VahnDijk, “The waterproofing system by Westcoat—the multi-layered acrylic cement method—is by far the most effective and beautiful” for second-floor balconies. Let’s see why second-floor balconies need an extra level of care.

2.1 Exposure to Elements

Unlike ground-level patios or decks, second-floor balconies often endure harsher wind, rain, and temperature fluctuations. The barrier system must be robust enough to handle these stressors.

2.2 Risk of Leaks into Living Spaces

Water penetrating through a second-floor balcony can cause damage not just to the structure itself but also to the rooms below. Ceiling stains, compromised electrical systems, and mold growth in the joists are all potential risks.

2.3 Drainage Complexity

Elevated balconies typically incorporate gutters or scuppers that direct water away from the building. If these drainage elements fail or clog, water can accumulate and seep into the structure. A consistent slope of at least one-quarter inch per foot is usually recommended for effective drainage.


3. Effective Waterproofing Systems: A Look at Westcoat

If you’re looking to waterproof a second-floor balcony (or any elevated outdoor space), one of the premier methods recommended by Ken is Westcoat. This system uses multi-layer acrylic cement that can protect against moisture while delivering a visually appealing finish.

3.1 Why Acrylic Cement?

Acrylic cement stands out for its flexibility. Homes expand and contract due to temperature changes, seismic activity, and basic settling. Rigid coatings are more likely to crack over time, allowing moisture to seep in. The acrylic layers in Westcoat offer durability and slight flexibility, significantly reducing the risk of cracks.

3.2 Multi-Layer Application

The Westcoat system involves several stages:

  1. Surface Preparation: Cleaning, repairing, and ensuring the plywood substrate or existing concrete is stable.
  2. Base Layer: An initial coating that adheres to the surface and sets a foundation.
  3. Reinforcing Fabric: In some installations, a mesh or fabric is used to strengthen high-stress areas (corners, seams).
  4. Acrylic Cement Layers: Multiple coats that form a durable, waterproof shield.
  5. Topcoat or Sealer: A final coat for aesthetics and additional protection against foot traffic, UV rays, and mild chemical exposure.

3.3 Aesthetics and Customization

One of the bonuses of the Westcoat system is its customizable finish. You can choose different textures, colors, and patterns to blend with your home’s existing architectural theme. The resulting appearance can be both practical and visually striking.


4. How Long Will Rubber Deck Waterproofing Last?

Rubber coatings, also known as rubberized deck membranes, are another popular choice for some homeowners. They can effectively seal surfaces and are often easy to apply. However, there are some drawbacks.

4.1 Typical Lifespan

Ken notes that rubber waterproofing “will last a good number of years.” Under normal conditions, many rubber coatings can last between 5 to 10 years with proper maintenance. However, durability can vary based on quality of installation, climate, and specific product formulations.

4.2 Susceptibility to Damage

According to Ken, rubber coatings “are very susceptible to chemical harm, barbecues, hot coals—things like that.” Even small incidents, such as grease spills from a grill, can degrade the coating. Damaged areas can allow water infiltration if not repaired promptly.

4.3 Comparison to Acrylic Systems

  • Flexibility: Rubber membranes are generally flexible, but some can degrade faster in extreme temperatures or if exposed to harsh chemicals.
  • Aesthetics: Rubber coatings often have limited color and texture options compared to acrylic cements like Westcoat.
  • Maintenance: Rubber coatings may require more frequent reapplication or patching, especially if exposed to heavy foot traffic or harsh conditions.

5. Is It Better to Stain or Waterproof a Deck?

This question arises often, and Ken’s answer clarifies some misconceptions: “Staining would be only applicable to wood decks of some type of wood. Waterproofing a deck would typically be done over plywood.”

5.1 Staining Wood Decks

  • Function: Stain penetrates the wood, preserving its natural appearance while offering mild protection against moisture and UV rays.
  • Aesthetics: Stains come in various tints and transparencies, allowing the natural grain to show through.
  • Maintenance: Stained decks need reapplication every couple of years, depending on exposure and quality of the stain.

5.2 Waterproofing Over Plywood

  • Function: True waterproofing systems, such as multi-layer acrylic cement, create a sealed, impenetrable surface.
  • Aesthetics: While you can choose decorative finishes, the look is generally more contemporary than a wood grain finish.
  • Longevity: When properly installed, waterproofing systems tend to last longer than stain alone. They also provide more robust moisture protection.

5.3 Which One Is Right for You?

  • Wood Lovers: If you’re drawn to a natural wood aesthetic and your deck is indeed built with hardwood or pressure-treated wood, staining is a valid choice. You’ll still need to keep up with regular maintenance.
  • Maximum Moisture Protection: If your deck is made of plywood or you need ultimate defense against water, a waterproofing system is the way to go. This is especially true if the deck is elevated and located over living space.

6. Preparing for a Waterproofing Project

Whether you opt for rubber coatings, acrylic systems, or a stain, some preparatory steps are universal:

6.1 Assess Structural Integrity

  • Inspections: Hire a professional to look for hidden damage or areas needing reinforcement.
  • Repair and Replace: Address any rotted wood, corroded metal, or cracked concrete before applying a new waterproofing layer.

6.2 Ensure Proper Slope

Water must have a path to drain away from the balcony or deck. If the slope is inadequate or uneven, pooling will accelerate wear and tear on your waterproofing layer.

6.3 Consider Climate

In rainy or snowy climates, you may need additional or specialized coatings that can handle standing water or freeze-thaw cycles.

6.4 Understand Building Codes

Second-floor balconies, in particular, might be subject to stricter regulations regarding load capacity and waterproofing methods. Always check local building codes and permit requirements.


7. Maintenance Tips for Longevity

Once you’ve invested in a high-quality system, preserve its integrity through regular upkeep:

7.1 Clean Regularly

Remove debris such as leaves, dirt, and standing water. Organic matter can trap moisture, accelerating mold growth and compromising the surface.

7.2 Inspect Seams and Edges

Cracks often form at seams or edges where different materials meet. Address small fissures immediately with patch kits or professional repair to prevent larger issues.

7.3 Monitor Furniture Placement

Heavy furniture, planters, or grills can dent or wear down waterproof surfaces over time. Use protective pads or distribute weight evenly to reduce stress points.

7.4 Reapply Topcoats as Needed

Both acrylic and rubber systems can benefit from periodic recoating. Follow manufacturer guidelines or consult your contractor on recommended maintenance schedules.


8. The Value of Professional Expertise

While do-it-yourself approaches are tempting, especially for smaller repairs, second-floor balconies and decks demand precision and experience. Rock Solid Waterproofing, led by Ken VahnDijk, offers in-depth knowledge of the materials, local climate, and best practices. A professional inspection and installation can save you money long term by minimizing the likelihood of waterproofing failures.

8.1 Common DIY Pitfalls

  • Inadequate Prep: Skipping thorough cleaning or necessary repairs undermines even the best waterproofing product.
  • Wrong Product Choice: Not all coatings are created equal, and using the wrong one for your specific climate or substrate can lead to quick failures.
  • Insufficient Dry Times: Rushing the process between layers often results in subpar bonding and compromised durability.

8.2 Benefits of Hiring Experts

  • Accurate Diagnosis: Professionals can identify hidden structural issues before they become bigger problems.
  • Quality Materials: Contractors typically have access to premium products and specialized membranes.
  • Warranty and Peace of Mind: You’ll often receive a warranty covering labor and materials, ensuring that any future issues are addressed promptly.

9. Frequently Asked Questions

9.1 How Do I Choose the Right Coating for My Climate?

Research local weather conditions—rainfall, freeze-thaw cycles, intense sunlight. Speak with a reputable contractor who can recommend solutions like Westcoat or rubber membranes tailored to your specific environment.

9.2 Do I Need Permits for a Balcony Waterproofing Project?

In many jurisdictions, adding or significantly modifying a balcony can require permits. Always check local building codes and consult with professionals familiar with your region’s regulations.

9.3 How Often Should I Schedule Maintenance?

A yearly inspection is a good rule of thumb. Professionals can catch early signs of wear, allowing you to address them before water penetrates deeper layers.

9.4 Are There Eco-Friendly Waterproofing Options?

Some companies offer low-VOC (volatile organic compound) formulas. Speak with your contractor about green options that meet performance standards while reducing environmental impact.


10. Conclusion

Waterproofing your second-floor balcony or deck is a key investment in the longevity and safety of your home. Systems like Westcoat deliver long-lasting protection and aesthetic versatility, making them ideal for high-exposure areas. Rubber deck membranes can also be effective but may require greater caution around chemicals, heat, or heavy wear. If you have a wooden deck, staining is a valid choice—just remember that it offers less robust moisture protection than a full waterproofing system. Whichever method you choose, proper planning, expert installation, and routine maintenance are crucial for keeping moisture out and ensuring your outdoor living space remains a source of enjoyment rather than headaches. If you’re unsure about the best approach, consult a professional like Ken VahnDijk at Rock Solid Waterproofing, serving Portland, OR, Vancouver, WA, and the surrounding areas. An expert opinion can help you navigate local regulations, select appropriate materials, and achieve a waterproofing solution that stands the test of time.