Retrofit of existing structure to accommodate a green roof.
Intensive green roof weight and structure.
Green roofs may come in an endless variety of shapes and sizes from high rise public parks and lush rooftop gardens to tranquil urban spaces but there is one critical factor that has a major impact on them all weight.
Green roof weight can range from hundreds of tons for an intensive green roof such as a small urban park or garden to just a couple of hundred kilos for a lightweight extensive green roof system like urbanscape featuring a lush mix of sedum vegetation.
Intensive green roofs are essentially roof gardens and may also need to allow for the additional weight of paving and terracing furniture and even trees.
A feasibility study should be conducted on an existing structure to determine the capacity of a building to accept the weight of a green roof.
An interesting example of an intensive green roof is manaton the award winning private house on dartmoor that uses local meadow grass to blend the family home into the landscape.
Once the plants are installed and the soil is moist these rooftop green spaces can weigh as much as 150 pounds per square foot.
Therefore different drainage and filtration build up are required for increased drainage capacity and load bearing.
The venny green roof has shallow substrates on two types of roof the first roof is on shipping containers and is designed for a dead load of 250kg m 2 and live load of 100kg m 2.
Other than the overall weight of the system dictating the construction of the supporting structure there s a huge scope for the design of a roof garden.
Photo by andrew wutke.
A roof may have enough structural capacity built in to support a green roof of a given depth or reinforcement may be needed.
Intensive green roofs and roof gardens.
However it is important to establish the landscape finish you are looking to achieve which will then have a direct impact on the system and.
You can compare an intensive roof to a normal garden and this is why an intensive green roof is also known as a roof garden or garden roof.
The second trussed roof is designed for a dead load of 160kg m 2 and a live load of 40kg m 2.
Intensive green roofs weigh from 35 pounds to beyond 100 pounds per square foot when dry it is all a matter of the soil depth which is affected by the amount of mounding that is used.
The depth of an intensive green roof ranges from 15 cm to as much as 150 cm and can easily weigh as much 300 to more than 1500 kg m2.
The planting medium in intensive green roofs starts at 6 inches although you will see some wiggle room in various definitions and really elaborate designs may exceed a couple feed.
To bear this weight an expensive custom support structure is required.
Intensive green roofs are far more complex than the sedum roofs.
Unlike conventional earth covered structures garden roof assemblies are lightweight and can be installed on a wide variety of new and existing structures.
Garden roof assembly hydrotech s garden roof assemblies combine the proven performance of our monolithic membrane 6125 roofing waterproofing with proven green technology.
