Open space 30% requirement at Ground Level only?

Hi Susan, for projects that achieve a density of 1.5 floor-area ratio (FAR), and are physically accessible, extensive or intensive vegetated roofs can be used toward the minimum 25% vegetation requirement, and qualifying roof-based physically accessible paving areas can be used toward credit compliance.

How is "accessible" defined relative to a green roof - our green roof is adjacent-accessible, but it is not designed to be walked on or played on. The paver areas adjacent to the roof is accessible, does that comply? Or does the green roof need to be robust enough to support people walking on it?

Hey Jonathan,

We had a similar question which prompted some research, and our understanding is that all green roofs (extensive or intensive) can count towards the vegetation requirement, but in order to count as open space, they do actually need to be accessible (i.e. able to be walked on/played on). Accessibly pavers at roof level would comply assuming the FAR requirements Karin references is met.

If anyone has a different understanding I'd love to discuss!

Jake

The green roof should not basically be "able to be walked on/ played on". Reference guide states: the open space can include "a garden space with a diversity of vegetation types and species that provide opportunities for year-round visual interest." This supports the credit intent to encourage interaction with the environment. 

Hi everyone! I would like to know it the project can achieve 30% of open space ONLY with green roofs. Since our project is zero lot line and has a FAR of 1.5. Could this be an option to achieve this credit?

Hi Victoria,

I don't see why your project wouldn't be able to achieve it as a zero lot line project as long as they're accessible and meet the open space criteria.

Hi Victoria, Yes I agree with Emily. You can even go for credit substitution using v4.1 which eliminates the FAR requirement. Check this out: https://www.usgbc.org/articles/substitute-any-leed-v4-credit-leed-v41