How Much Does A Green Roof Weigh

How much does a green roof cost.

How much does a green roof weigh.

Weight of standard sedum roof a standard sedum roof has a saturated weight of about 80 kg m. When saturated with water in the summertime when the plants are at their biggest and heaviest the mats weigh 40 45kg m2. Thus the saturated weight of a 3 inch deep system is about 20 pounds per square foot including a mature plant cover. On average an extensive green roof weighs between 10 30 lbs per square foot.

Biodiverse green roofs are low maintenance roofs designed to create or replace natural habitats. 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. Check that there are no areas of damp rotting wood. For example roofmeadow green roofs engineered to be both lightweight and efficient generally weigh about 6 75 pounds per square foot for each inch of media depth.

If necessary this weight can be reduced to approximately 40 kg m for roofs that can only bear a lightweight green roof system. So in dry state 50 m2 traditional green roof weighs around 5 tons while a similar sized urbanscape roof weighs just 1 ton scale this up and a 1 000 m2 traditional green roof space requires 100 tons of material to be brought on the roof and the urbanscape version only 20 tons and can be called a light weight green roof. A flat roof built using the enviromat green roof system will weigh the following. Holds up to 9 litres of water per square metre so saturated weight is 9kg m2.

The weight of biodiverse green roofs varies according to the needs of the plant species required. System depth dry weight saturated weight 5 25 media depth 17 22 lbs ft 2 29 34 lbs ft 2 6 media depth 19 25 lbs ft 2 33 39 lbs ft 2. As a guide prices can vary from 50 m for a sedum roof to 200 m for a fully planted intensive roof the cost of any reinforcement needed to the roof and or wall structures is additional to this. Let s crunch some numbers.

The cost will vary with the green roof system and the particular situation. A semi intensive green roof weighs between 30 50 lbs per square foot. They can be specified to meet local biodiversity action plans or to support specific flora and fauna including bats bees butterflies birds and so on.