The short answer is no, roofing felt should not be applied directly to a green roof. Green roofs require specific waterproofing measures to ensure the longevity and effectiveness of the system. Instead of using roofing felt, a separate waterproofing membrane designed for green roofs is typically utilized.
Why Roofing Felt is Not Suitable for Green Roofs
Although roofing felt offers benefits in traditional roofing systems, it is not suitable for green roofs due to several factors. First, roofing felt is not designed to withstand the constant exposure to moisture that a green roof experiences. Over time, the felt can degrade, leading to potential leaks and damage to the roof structure.
Second, roofing felt lacks the necessary root barrier properties needed to prevent plant roots from penetrating and damaging the roof. Green roofs utilize specific root barriers to ensure that plant roots do not compromise the waterproofing and structural integrity of the roof. Roofing felt does not provide this level of protection and can be easily breached by aggressive root systems.
Third, the use of roofing felt can interfere with the overall drainage system of a green roof. The layers in a green roof are carefully designed to allow for adequate water absorption, retention, and controlled drainage. The inclusion of roofing felt can disrupt this system, leading to poor water management and potential water damage to the roof.
Alternate Waterproofing for Green Roofs
To properly waterproof a green roof, specialized waterproofing membranes are used. These membranes are specifically designed for green roofs and can withstand the unique challenges posed by vegetation and moisture exposure. They offer comprehensive protection against water infiltration, root penetration, and ensure optimal drainage for the longevity of the green roof.
While roofing felt has its merits in traditional roofing construction, it is not suitable for use in green roofs. Applying roofing felt to a green roof can result in moisture issues, compromised structural integrity, and poor water management. Instead, specialized waterproofing membranes designed for green roofs should be used to ensure the success and longevity of this sustainable roofing solution. It is crucial to consult with a professional roofer experienced in green roof installations to ensure proper waterproofing techniques are employed for a successful green roof project.