Green Roof Weight Load

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.

Green roof weight load. Multi layer extensive roof greening from 0 5 roof pitch medium layer height approx. Modern green roofs typically use lightweight engineered soils with very light drainage and insulation layers. 120 kg m drought compatible sedum plants grasses herbs approx. 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 traditional green roof can exert a load of up to 250 kg per m2 and that inevitably means a strong building is required to support the weight. Mid range 5 inch systems weigh approximately 34 pounds per square foot and are compatible with wood or steel decks. 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. 25 species medium maintenance 2 3 times per year.

Heavier intensive green roofs generally require a concrete supporting deck. Soil does not necessarily occupy the full depth of the assembly. Astm e2397 is the established standard procedure for determining the dead and live loads associated with green roof systems. Variations from the design weight can lead to structural failure.

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 first conservative assumption by structural engineers is to use the full saturated weight of 110 pcf for the full depth of the green roof assembly. In older buildings or new build this may require costly structural reinforcement which in some cases may prove prohibitively expensive. The second trussed roof is designed for a dead load of 160kg m 2 and a live load of 40kg m 2.