Green roofs, which are roofs that have been planted with grasses, flowers, or other vegetation, are gaining popularity among homeowners wishing to make eco-friendly choices and decrease their carbon footprint. While there are some benefits to these roofs, they are not the right choice for every homeowner. Read on to learn more about the benefits and challenges of green roofs so you can make a more informed decision as to whether a green roof is right for you.
Benefits of Green Roofs
They eat up carbon dioxide and release oxygen.
By choosing a green roof, you are doing your part to protect the planet. Carbon dioxide is one of the most prevalent greenhouse gasses. The plants on your green roof will utilize some carbon dioxide, which will help fight global warming. The carbon dioxide reduction achieved by a single green roof is pretty small, but every little bit helps. Plants also release oxygen, which is important since humans and animals need oxygen to survive -- and levels of atmospheric oxygen have been declining.
They provide an added layer of insulation.
You, as well as the environment, will benefit from green roofing in terms of energy conservation. The soil and plants add an extra layer of insulation, reducing heat transfer through your roof. This leads to lower heating and air conditioning bills, as well as a more comfortable home and a reduced need for supplemental fiberglass or cotton insulation.
They reduce the urban heat island effect.
The urban heat island effect is a phenomenon in which the temperature in highly populated areas rises a few degrees above that of the surrounding, less-populated areas. This temperature increase occurs because all of the dark roofs and pavements absorb heat from the sun. The urban heat island effect leads to an increase in cooling costs, and it also makes being outside less comfortable in the summer. Green roofs help fight the urban heat island effect because they absorb less heat than black roofs. If you live in a populated area, this is a good reason to consider a green roof.
Challenges of Green Roofs
Green roofs can be tough to maintain.
When there is enough rain, green roofs don't require so much maintenance, but as soon as a drought arrives, you'll find yourself spending a lot of time watering your roof to keep it green. You will also have to periodically re-plant the roof or hire someone to do this for you. Other maintenance tasks will include removing sticks and leaves from the roof, deadheading any flowers, and making sure the gutters remain clear of debris. If you don't like the idea of putting time into your roof, a green roof might not be the best choice for you.
The up-front cost is high.
A green roof may save you money in the long run by reducing energy costs, but they can be quite expensive up-front. Expect to pay between $15 and $20 per square foot for green roofing. For comparison, a standard asphalt roof costs around $1 - $4 per square foot, and corrosion-resistant steel roofing costs around $7 - $10 per square foot.
Not all homes are built to support the weight of a green roof.
Green roofs are notably more heavy than metal, asphalt, or cedar roofs. If you're having a new home built, this is not a big concern, since your architect can design the home to support this additional weight. However, if you're considering retrofitting your existing home with a green roof, you will need to have a structural engineer evaluate it and make sure it's strong enough to support a green roof first. Many older homes are not.
To learn more about green roofing, speak with a roofing contractor in your area.