Residential Green Roof

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Whenever you hear the sound of rain falling on your roof during a storm in the summer, you may also be hearing the sound of a missed opportunity to put your roof to better use. Many homeowners are discovering the immense importance of green roofing for their houses or simply covering the flat sections of their roofs with small plants that grow a few inches on engineered soil.

Besides reducing heating and cooling costs and increasing the longevity of your roof, there are several reasons why you should install a green roof if you have the chance. Read on to find out the benefits that will come your way by having a green roof residential system installed in your home.

Understanding the Green Roof

There is much more that goes into the design of a green roof than what the eye sees. What you see is patches of small vegetation growing on pebble dotted sections or some other growing medium, yet the real action takes place between the layers of the green surface and the roof.

A green roof is usually placed like a rug on the surface of a roof where there isn’t much foot traffic. A special membrane is used to cover the roof itself, and it is on this membrane that the plants will be grown. The special membrane is composed of either a cold applied layer of synthetic rubber or hot applied rubberized asphalt. When these are combined with roof repellant materials, they are able to block moisture and roots from causing any serious damage to the roof.

Pebbles or other geo-composite materials are used to form a drainage layer at the very top of the membrane. Most residential green roofs feature crops of hardy, low lying plants such as chives, sedum, delosperma and talinum. These plants are excellent in providing a natural sponge for water and protecting the roofing material, thus adding to its longevity.

It will interest you to note that a well-designed residential green roof requires very low maintenance. Drought-resistant plants perform well most of the time and only require supplemental water in very extreme conditions. You will also have to weed them either once or twice a year with no other care and maintenance activity required.

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The Real Benefits of Having a Residential Green Roof

As alluded to earlier, there are a number of benefits to installing green roof systems. These benefits are not just to the homeowners but also to the general public and the environment as well. Some of the benefits are given below.

Benefits to the Homeowner

Residential green roofs benefit the homeowners in the following ways:

  • Enhances energy efficiency– Green roofs are great at offering excellent insulation, thus helping in temperature regulation during hot and the cold months. The result of this is reduced energy bills to the homeowner.
  • Roofing membrane durability– One way of increasing the roofing membrane durability is to install a residential green roof. The roof will reduce the exposure of the roof membrane to large temperature variations as well as the ultraviolet rays of the sun which might cause micro tearing, leading to a shorter roof lifespan.
  • Green roofs for noise reduction– Green roofs are effective when it comes to noise attenuation. An intensive green roof can reduce noise by up to 50 decibels while an extensive green roof can reduce external noise by up to 40 decibels.
  • Fire retardation– Since green roofs have a low burning load, they can slow down the effects in the unfortunate instance of a fire breakout.
  • Marketability of the home– Residential green roofs have more value and enhance the building’s marketability. Such buildings can be easily identified as symbols of the green building movement and they can act as incentives for buyers or investors.

Public Benefits of Green Roofs

The beauty of green roofs is that they don’t just benefit the homeowner, but they also have a special appeal to the general public. This is due to the points given below.

Aesthetic improvement – Residential green roofs have a special aesthetic appeal to the general public since they are easy to maintain and effective in making the built environment beautiful and enhancing investment opportunities.

Waste diversion – Green roof systems can contribute to waste diversion in a number of ways, including:

  • Increasing the longevity of the waterproofing membranes.
  • Using recycled materials as the growing medium.
  • Prolonging the lifespan of HVAC systems due to reduced loads on the systems.

Storm water management – When residential green roofs are in place, storm water management is enhanced in the following ways:

  • It stores water in the roofing substrate. The water will be used later by the plants before being released back into the atmosphere through transpiration.
  • Green roofs retain and modify the temperature of the rain water, thus acting as natural filters to any flow that results in runoff.
  • Green roofs reduce the amount of storm water and also delay the time at which run off happens, thus leading to reduced stress on the sewer systems during heavy flow.

Improved air quality – The plants present on a green roof act like air purifiers that filter in noxious gases and release fresh oxygen into the environment. They also capture airborne pollutants and other atmospheric accumulations to make the air fresh and clean for breathing.


Types of Residential Green Roof Systems

There are basically three different types of residential green roof systems. They are:

  • Extensive green roofs – These roofs are designed for environmental solutions and are ideal for low sloped retrofits and residential roofs. They can be used for growing desert grasses and they won’t require any watering after the first year.
  • Intensive green roofs – These roofs are also known as rooftop gardens. They can serve a number of purposes such as vegetable gardens, playgrounds, or walkways. They can also accommodate diverse plants and trees and require regular care and maintenance.
  • Semi-intensive green roofs – These green roofs feature a combination of both the intensive and extensive green roof designs. It is a blend seeking to benefit from both the environmental gains as well as the diverse gardening opportunities offered by green roofs.