The green roof is becoming more prevalent today, showing up in more and more areas. It's one of the most blatant eco-friendly forms of construction, and they are built for several reasons beyond looking environmentally friendly.
What is green roofing?
A green roof is made of actual plant life. This involves placing soil and then planting plants, grass, or other "green" elements into the roof. To prevent leakage of water into the building the roof is built on there is a waterproof layer of some kind underneath the soil. In some cases, extra construction is done to help adjust for irrigation or to manage drainage of the roof.
Why use green roofs?
There are several benefits to green roofs. Here are some of the major ones:
- They act as insulation, reducing the amount of heating or cooling the environment normally affects the building with
- Helps insulation for sound
- The durability of the roof is increased by having a naturally long lifespan
- Cut back on rain drainage (as it's absorbed by the roof)
- Acts as a natural filter for rainwater
- Acts as a natural filter for certain types of gases, including carbon dioxide
- Ability to grow food, such as fruits and vegetables
- Ability to grow flowers for various purposes
How do you build a green roof?
There are three levels of green roofs. These are:
An "intensive" green roof requires the most work. These have a defect level level and are meant to host larger plants or full lawns. These mimic parks, only placed on top of a building roof. Some may even contain walkways and benches to allow friendly access to the plant life.
To do green roofing with minimal work and labor, an "extensive" green roof would be the best choice. These are built to support themselves and do not require as much maintenance. In many cases, only annual maintenance is required for these types of roofs. They often contain only a very thin layer of soil and have robust plant life, such as moss or plants with higher levels of hardiness than others.
The major disadvantage to a green roof is the initial cost. Sometimes the structural integrity of the building needs to be adjusted to help support the roof. Root barriers are often needed to be installed to prevent the plant life from breaking through the building structure. However, this disadvantage is often disregarded as the cost savings for other elements (insulation, energy costs) is reduced heavily and can recuperate all costs in a relatively short amount of time.
Green roofing is something that is becoming more prominent, and with an increase in the "green-friendly" attitude, these rooftops may begin surfacing in more cities around the world.