The Benefits of Using Backer Rod and Sealant Over Great Foam for a Tighter Seal
When it comes to sealing gaps and joints in construction, selecting the right materials can make a significant difference in both energy efficiency and long-term durability. While expanding foam (commonly referred to as “Great Foam”) is a popular option, using a combination of backer rod and sealant often provides a superior seal, especially for air leakage control. Here’s why:
1. Improved Seal Performance
Backer rods are designed to create a proper joint profile, allowing the sealant to adhere effectively. Unlike expanding foam, which can be inconsistent in expansion and coverage, backer rods ensure a uniform depth for the sealant, reducing the risk of cracking and air leakage over time.
2. Flexibility and Movement Accommodation
Buildings naturally expand and contract due to temperature changes and settling. Backer rods provide a flexible backing that allows the sealant to move with the structure, preventing premature failure. Expanding foam, on the other hand, can become brittle and may not accommodate movement as effectively, leading to cracks and gaps forming.
3. Better Moisture Resistance
One of the key advantages of a backer rod and sealant system is its ability to resist water penetration. Expanding foam can absorb moisture over time, potentially leading to mold growth and material degradation. The proper use of a backer rod with a high-quality sealant creates a waterproof barrier that is more reliable in the long run.
4. Enhanced Energy Efficiency
Since backer rods help ensure a proper sealant depth, they contribute to a more airtight seal, reducing energy loss. This is particularly important in air sealing applications, such as around windows, doors, and building envelope penetrations. Expanding foam can sometimes leave small gaps or shrink over time, compromising its insulating properties. Additionally, expanding foam doesn’t always create a complete seal, potentially leaving tiny holes that allow air infiltration and energy loss.
5. Cleaner and More Professional Finish
Using backer rod and sealant results in a smoother, more aesthetically pleasing finish compared to the often rough and uneven surface left by expanding foam. This is especially important for visible areas where appearance matters, such as interior joints or exterior façade sealing.
6. Longer Lifespan and Reduced Maintenance
The combination of backer rod and sealant is designed for longevity. Unlike expanding foam, which can deteriorate with UV exposure and over time, a properly installed backer rod and sealant system provides a durable and low-maintenance solution that remains effective for years.
Conclusion
While expanding foam can be useful for certain insulation applications, it is not always the best choice for creating an airtight, long-lasting seal. Using backer rod and sealant ensures a more durable, flexible, and energy-efficient barrier that stands the test of time. For professional air sealing and energy efficiency solutions, consider investing in the right materials and techniques for a job well done.
At Alpine Energy Solutions, we proudly offer professional blower door testing and duct leakage testing services throughout Salida, CO, Buena Vista, CO, Poncha Springs, CO, Leadville, CO, and the surrounding areas of Chaffee County and Lake County. Whether you’re building a new home or improving an existing one, our testing services help ensure your property is energy efficient, code compliant, and comfortable year-round. Trust our team to help you identify air leaks, improve insulation performance, and achieve a tighter building envelope.