The best place to find this type of data is typically through public agency or semi-public agencies like universities or other organizations. But if you can’t find data specific to the 2-year 24-hour storm, there is an alternative compliance path published by USGBC in the ACP Documentation Guidance for Projects Outside the U.S.

If the manufacturer publishes or can provide the runoff coefficient for your system, use that. For other surfaces where the data is not available, chose the closest surface type from the credit form and go with that.

This is mostly a judgment call and if you’re concerned about questions during the review process, a great way to make your case is with photos or with a narrative describing your methodology to determine the slope.

NOAA provides a great resource for finding information on the 2-year 24-hour storm. For some locations in the U.S., the site allows you to navigate to a specific locale and generates a table of rainfall intensities, including for the 2-year 24-hour design storm. For the other states, it lets you download isopluvial maps.

No, the policy only has to cover purchasing performed by the building and site management. You don’t need to impose purchasing requirements on your tenants. Be sure to state the scope of your policy clearly to avoid confusion (in this case, purchases under the building management’s control). Remember that you do have to account for tenant purchases if you attempt any of the credits (with the exception that you can exempt up to 10% of the building’s floor area).

You do not need to attempt or achieve any purchasing credits to earn the prerequisite. Achievement of this prerequisite is based only on whether you create a compliant policy; no purchasing activity or documentation of compliance with the credits is required.

You can submit an existing policy with an amendment or attachment that addresses the missing requirements, as long as all new sections are officially adopted along with your existing policy. You may want to consider highlighting the required elements that are covered in your existing policy so that the LEED review team can easily confirm that you’ve addressed everything.

Yes, all lamps in the project building and site need to be included, unless they meet the exception criteria. This credit may be challenging to achieve on this type of project.

Reference Guide correction ID# 100002036 (released 10/1/2015) removes the requirement to purchase lamps during the performance period. Based on the correction language, it appears that teams can simply confirm that no lamps were needed. However, it is unclear whether teams should also confirm that existing installed lamps meet the credit threshold when pursuing this option. You may want to provide a lamp inventory (e.g., the “lamp purchasing plan” from EBOM 2009) to demonstrate that the overall building average is 70 picograms of mercury per lumen-hour or less.

Screw-based, integral self-ballasted compact fluorescent lamps can be excluded if they meet the voluntary guidelines for maximum mercury content published by NEMA. The guidelines are such that:

Lamps with input wattage of 0 ≤ 25 watts must have 4mg total mercury or lessLamps with input wattage of 25 ≤ 40 watts must have 5mg total mercury or less

If the manufacturer documentation confirms the mercury content is below these maximum mercury content values, than the lamps may be excluded.