Green Roof System 101: The Best Materials to Use & Benefits

a green roof with grass patches on a tall building

Ever since people built the first huts thousands of years ago, architecture has constantly been evolving. Today, there is a huge variety of architectural styles and techniques for constructing houses. Of course, this includes one of the most important parts of a house or building: the roof. Nowadays, roofs are not only meant to protect a home from exterior elements. There are many ways in which a person can take advantage of all the space a roof provides. Without a doubt, one of the best ways to achieve that is through a green roof system. The following guide will go over this important topic.

What Is a Green Roof System?

Succinctly defined, a green roof is a roof that uses a waterproofing membrane in order to allow vegetation of any kind to cover it partially or entirely. In many cases, green roof systems also use additional components such as root barriers, drainage systems, and irrigation systems. Ultimately, the goal of a green roof system it to make possible a balanced, sustainable and functional roof garden that utilizes vegetation to the advantage of the entire home. Although some people debate it, this does not include container gardens or plants that are kept in pots of any kind.

Apart from being aesthetically pleasant, green roof systems serve several purposes. To start with, they are capable of absorbing and utilizing rainwater, eliminating the possibility of roof damage that can lead to leaks and other problems. They also function as a form of insulation from potentially harmful external elements. Besides the architectural benefits they provide, green roofs are great for the environment. Not only do they create habitats for wildlife but also increase the production of oxygen. As if that was not enough, it has been proven that they help reduce stress.

How to Install a Green Roof System?

1. Prepare the Roof

Before doing anything else, it’s highly important to be sure that the roof is in perfect conditions. Not only that but it should not be too sloped. A flat roof works. However, if it’s at an angle, it shouldn’t be over 30 degrees. Of course, it’s highly important that the green roof gets a good amount of sunlight every day. With that in mind, you should remove any obstructions if it’s at all possible. If you can’t do it yourself, there are contractors who install green roof systems with residential applications.

2. Install Waterproofing Membrane

a worker installing a roof

It’s vitally important that there is at least one layer between the roof and the soil. A waterproofing membrane keeps the water from accumulating and seeping into your home. In the case of flat roofs, it may also provide a slight pitch to shed water towards the gutters.

3. Install Drainage Layer

a house's gutter system

In many cases, experts will install a drainage system that will take care of any surplus of water, eliminating the possibility of puddles being formed. This system is usually a combination of a draining layer and a gutter system.

4. Add Soil

After you completed the previous steps, it will be time to add the soil. Although regular soil can do the trick, there are specialized brands of green roof soil that offer a more apt product for this end. These special mixtures combine regular soil with organic and mineral additives such as peat, wood chips, humus, clay, and sand. This fantastic combination helps achieve better water retention, improved permeability, and added erosion control.

5. Begin Planting

Logically, the last step in the process is planting the vegetation. This can consist of any possible combination of garden plants as long as they are well-suited for the type of climate. Of course, an extensive green roof system will be able to sustain the life of bigger plants.

What Are the Best Materials for a Green Roof System?

As with anything, residential green roof systems benefit greatly from using high-quality materials. The membrane can be made of either asphalt roofing felt, a single-ply rubber membrane or a fluid-applied membrane. The drainage layer is usually comprised of plastic channels or a natural substrate.

4 Benefits of Installing a Green Roof System

a house with a green roof system

1. They Are Energy Efficient

A green roof system can help save an important amount of energy while generating fewer greenhouse gas emissions. They also give isolation, reducing the amount of heat that would be lost through a normal roof. This reduces the amount of energy necessary to heat up the house. Additionally, plants help trap dust from the air, cleaning it and cooling it down.

2. They Can Serve as a Habitat for Wildlife

Because they are attracted to peaceful places with a lot of vegetation, animals will often nest on green roofs. This is helpful for species that struggle for survival. Also, it is especially true for ground-nesting birds such as Killdeer.

3. They Last Longer

After becoming green, a roof’s lifespan becomes greatly extended. The main reason for this is that vegetation and soil protect the foundation of the roof from UV rays and extreme changes in temperature. Of course, this translates to big money savings in the long run.

4. They Provide Extra Space

If you stop to think about it, roofs don’t need to be unused areas. Green roofs are great for creating new spaces that can be enjoyed socially or recreationally. Without a doubt, houses and buildings that do not have gardens will be the most benefited from this new space.

To Conclude with

It’s clear that green roofs are not just an interesting accessory. In reality, they are improved versions of the classic, barren roof. Apart from beauty, they provide various benefits to the architecture of a home, increasing its value by a considerable amount. They also help conserve the environment and even provide a living space for beautiful animals. If there is an addition for your home that is all pros and no cons, this is definitely it.

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