Roof felt, also known as roofing felt or tar paper, is a thin material made from a combination of fiberglass, tar, and asphalt. It is commonly used as an underlayment on roofs to provide an extra layer of protection against leaks and moisture. Many homeowners wonder if it is possible to apply sealant over roof felt to further enhance its waterproofing properties. In this article, we will explore this question and discuss the potential benefits and drawbacks of applying sealant to roof felt.
Understanding the Purpose of Roof Felt
Before delving into the topic, it is essential to understand the purpose of roof felt and why it is widely used in roofing projects. Roof felt acts as a moisture barrier that helps to prevent water from seeping into the underlying layers of a roof. It can also provide additional insulation and protect against wind-driven rain or ice dams.
Benefits of Applying Sealant Over Roof Felt
- Enhanced Waterproofing: One of the primary reasons homeowners consider applying sealant over roof felt is to further enhance its waterproofing capabilities. Roof felt alone is designed to be water-resistant, but it may not offer complete protection against heavy rain or extreme weather conditions. Applying a layer of sealant can create an additional barrier, reducing the chances of water penetration.
- Increased Durability: Roof felt can be vulnerable to damage from UV rays, moisture, and general wear and tear. By adding a layer of sealant, you can enhance the durability of the roof felt, making it more resistant to the elements and extending its lifespan.
- Improved Energy Efficiency: Sealant can also act as an extra layer of insulation, helping to improve the energy efficiency of a building. By reducing heat transfer, sealant can help maintain a more comfortable indoor temperature and potentially lower energy consumption.
Potential Drawbacks of Applying Sealant Over Roof Felt
- Reduced Breathability: Roof felt is typically designed to allow for some level of breathability, allowing any moisture that may accumulate to evaporate. Applying a thick layer of sealant over roof felt can hinder this natural process and potentially trap moisture between the layers, leading to rot, mildew, or mold growth.
- Difficulty in Detection and Repairing Underlying Issues: Applying sealant over roof felt can make it challenging to identify and address any underlying issues within the roofing system. If leaks or damage occur, the sealant can make it difficult to locate the source, making repairs more complicated and time-consuming.
- Increased Weight on the Roof: The application of sealant over roof felt adds additional weight to the roofing system. While the increase may seem minimal, it is important to consider the long-term impact, especially in regions with heavy snowfall. The added weight may put stress on the roof structure and potentially lead to structural issues over time.
Considerations and Recommendations
Before deciding to apply sealant over roof felt, it is crucial to consider the specific circumstances and consult with a professional roofer. They can evaluate the condition of the existing roof felt, identify any underlying issues, and provide advice on the best course of action. In some cases, they may recommend alternative solutions such as roof coatings specifically designed for roof felt, which offer the benefits of enhanced waterproofing and durability without compromising breathability.
While it may be possible to apply sealant over roof felt, it is essential to carefully weigh the potential benefits and drawbacks before proceeding. Enhanced waterproofing and increased roof durability may be appealing, but one must also consider factors such as reduced breathability and added weight. Seeking professional guidance is crucial to ensure the best decision is made for the specific roofing system and circumstances.