Hello everyone!
I am pretty new at LEED, and I am working on a building in urban areas that will earn SS credit 2. Credit Requirements specifies that "pedestrian-oriented hardscape areas can contribute to credit compliance. For such projects, a minimum of 25% of the open space counted must be vegetated." while LEEDUser Bird's eye view states that "25% of the required open space must be vegetated". It's not exactly the same thing for me. For example, let's say that I have a site area of 5 000 m2. I need to provide 20% of open space, so 1 000 m2. If the building site actually provide 2 000 m2 of open space, what is the actual area of vegetated space required? Is it 25% of the required 1 000 m2 or 25% or the counted 2 000 m2? It's not very clear for me, so thanks for your help!
Tristan Roberts
RepresentativeVermont House of Representatives
LEEDuser Expert
11477 thumbs up
February 25, 2011 - 9:22 am
Valentin, you bring up a good point, and I am going to edit LEEDuser's language accordingly. I think from the LEED Reference Guide (pages 85 and 87) it is clear that the 25% should be counted against the total open space (2,000 m2), not just the minimum required.
Valentin Grimaud
Thermal EngineerTERAO Green Building Engineering
43 thumbs up
February 25, 2011 - 10:06 am
Thanks Tristan for your quick answer.
Just a further clarification, using the same example as above. I'm not sure if I am properly doing my calculation. I have 2 000 m2 of hardscape plus a garden roof. Do I need to add the surface of the garden roof to the surface of the hardscape, and then calculate if 25% of the total is actually vegetated, or do I need to check if the surface of the garden roof is equal to 25% of the surface of the hardscape?
Tristan Roberts
RepresentativeVermont House of Representatives
LEEDuser Expert
11477 thumbs up
February 25, 2011 - 10:11 am
I think the first method is correct—take the total open space being claimed, and multiply by 0.25.
Valentin Grimaud
Thermal EngineerTERAO Green Building Engineering
43 thumbs up
February 27, 2011 - 8:24 am
Tristan, what do you think of this interpretation of the vegetated space requirement: in case of SSc2, you can take into account hardscape, but in order to do this, the hardscape must be at least 25% vegetated. I think it's more consistent with the idea of the credit, which intent to reintroduce nature into urban area. In this idea, it's not the sum of hardscape + vegetated roof that need to have a 25:75 ration of vegetated area, but only the hardscape, and the vegetated roof come as a plus. What do you think of this interpretation?
Tristan Roberts
RepresentativeVermont House of Representatives
LEEDuser Expert
11477 thumbs up
February 27, 2011 - 3:28 pm
Valentin, I think what you are describing is a more stringent path than the one required by LEED. If you want to interpret it that way, I would encourage it, but I wouldn't consider it necessary.