Have you ever been sitting on your roof, wishing it wasn’t so boring? Ok, maybe you’re not sitting on your roof, but perhaps you’re looking for more opportunities to build a more sustainable future. Here’s a few reasons why you should consider installing a green roof on your residence.
Ok, but what is a green roof? A green roof is a vegetated roofing system that is integrated into a standard roof. They consist of a waterproof layer, root barrier, drainage layer, irrigation system, soil, and vegetation; not just some dirt and plants thrown on a roof. Adding a green roof to your home would provide environmental, economic, and aesthetic benefits.
Green roofs improve stormwater management, controlling stormwater runoff and retention. On standard roofs, precipitation picks up any dirt, contaminants, and excess nutrients and runs off into the storm drains. The storm drains then carry the contaminated water to nearby bodies of water, polluting the local ecosystem. Excessive storm water runoff can lead to flooding, erosion, and poor water quality causing additional damage to these ecosystems.
According to a study conducted by the Center for Green Roof Research at Pennsylvania State University, standard roofs retain an average of 24% of rainfall, while green roofs retain an average of 80%. By retaining nearly four times the amount of rainfall, green roofs drastically reduce storm water runoff and prevent flooding.
Green roofs also reduce the urban heat island effect. The urban heat island effect occurs in more urbanized areas that have higher average temperatures due to dark roofing and asphalt absorbing and retaining heat energy. Green roofs cover the dark roofing with vegetation, which absorbs less heat energy reducing temperatures.
Green roofs will reduce energy costs over time, saving the home owner money. Unlike thin-layered standard roofs, green roofs are composed of multiple layers. This makes green roofs natural insulators, lowering the change in temperature of buildings causing less strain on HVAC systems.This ultimately leads to savings on energy costs.
Green roofs extend roof life by providing a layer of protection against direct UV radiation and extreme temperatures. Green roofs have an estimated lifespan of 40 years and a 2,000 sq ft green roof could save approximately $200,000 in maintenance and energy costs over its lifetime. This value is substantially greater than the cost of installation for a green roof of this size.
Thanks to their environmental benefits, many urban areas have rebate and incentive programs for choosing to install a green roof on your home. In the District of Columbia, the Department of Energy and Environment (DOEE) has a rebate program for voluntary properties that offers a $15 rebate per square foot. The only requirement for this program is to be located within a municipal storm sewer system. Programs like this can make green roof ownership surprisingly affordable.
Depending on vegetation planted, green roofs can be incredibly self-sustaining. Plants such as succulents and sedum require little maintenance, while grasses and flowering plants may require more care. Typically, a green roof only needs to be maintenanced 2-3 times per year.
Many plants common for green roofs attract pollinators, creating rooftop butterfly gardens. They increase biodiversity by providing habitats to local flora and fauna, such as various bird species. Due to the inherent elevation of green roofs, you do not have to worry about potential garden pests such as deer and rabbits eating your garden.
If you’re interested in pursuing a green roof installation, contact us or fill out our request for a quote form on our website. Take the next step to a more sustainable and beautiful world.
