Green roof waterproofing for living roof gardens

View of green roof on modern buildings and other residential buildings

Did you know that rooftop gardens became popular in the US in the 1890s and that is where Madison Square Garden got its name?

Roof gardens, also known as green roofs, are a popular commercial or strata building option, due to their environmental, aesthetic and wellbeing benefits.

Let’s unpack green roofs and green roof waterproofing with you.

Outdoor garden on rooftop

Roof garden requirements

Roof gardens would generally be classified as intensive gardens. They would need to hold soil up to 1m deep to be able to support vegetation or planter boxes, trees, as well as structural work like concrete seating areas, decking and paving.

The waterproof membrane required to support a flat roof garden would firstly need to support the weight per square metre and be durable enough to withstand any plant treatments and weather conditions. In larger commercial or strata type buildings, the membrane would also need to support any structural movement.

Plants on the roof of a building

Benefits of a green roof, roof garden or living roof

Green roofs or roof gardens are generally installed on flat roofs. Flat roofs are energy efficient, are more affordable (excluding the landscaping costs) and require less maintenance than sloped roofs. With the right maintenance plan in place for the roof design, the roof can last for decades.

Green roofs or living roofs are known to insulate a building, requiring less cooling or heating, resulting in less emissions.

They improve sound, generate oxygen and act as a filtration system for rainwater by capturing pollutants. Green roofs can also decelerate water runoff, which has been proven over recent months with the wet weather conditions we’ve been experiencing.

Man waterproofing a rooftop

Green roof membrane choices

As roof gardens will be home to various vegetation types, including trees and other diverse root systems, waterproofing technology becomes essential in selecting a suitable waterproofing membrane.

An option we have previously featured in one of our blogs is the Ardex Root Repell™ which is a root repellent membrane that discourages root growth without harming the plants.

Two men smiling at the camera while inside the office

It’s essential to get it right the first time

With all the great and versatile benefits of choosing a green roof, we must emphasise the importance of getting flat roof waterproofing right and selecting the correct flat roof waterproofing solution, membrane and maintenance plan. The alternative will become incredibly costly in the long run.

To find out more about waterproofing green roofs, contact us or take a look at other blogs.

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