Hi Alysson,

LEED stepped it up a notch in 2009 by implementing the WE prerequisite 1: a mandatory 20% water use reduction – not including irrigation or process water reduction, which are separate credits.

This means a project must use strategies to reduce the buildings water consumption for all bathroom fixtures and kitchen sink faucets a minimum of 20% combined, just to be able to qualify for LEED certification.

Water Efficiency credit 3 (WEc 3) rewards projects that achieve a 30% water use reduction with 2 points, 40% will get 3 points and 50% earns 4 points for that credit. A 45% reduction will earn an Innovation in Design (ID) point for Exemplary Performance.

In the previous version of LEED (NC 2.2 or equivalent) there was no WE prerequisite and a project could earn a point for achieving a 20% reduction. This is similar the Energy and Atmosphere credit 1 (EAC 1), when, after June 26, 2007 projects must achieve a minimum of 2 points to qualify for certification. The difference being a prerequisite earns no points.

The prerequisite and credit deals with potable water specifically for: water closets (toilets), urinals, lavatory faucets (public and private), showers and kitchen faucets. Not included in the credit are: commercial steam cookers, commercial dishwashers, commercial ice makers, clothes washers (commercial and residential) and dishwashers.

I hope this helps.

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