LEED NC: Existing or New Building

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I have a unique situation where the architect is taking an existing building
and majorly renovating it (definition of major per LEED is HVAC, envelope
and interior spaces) and then building an addition which is roughly the same
size of the existing building, give or take a 1000 sqft.

Has anyone run into this before or have any insight that might help me
explain which avenue to take to my boss? I am currently thinking new
building, but if it was existing then that helps me even more.

--
Rob Hudson

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The baselines for the existing portion are what is there now.

The baselines for the new portion (addition) are ASHRAE definitions.

This should help considerably in your overall energy efficiency gains.

It all comes down to % new vs. % existing, on how much you can gain.

Jorge E. Torres Coto

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Yes, I agree that i should use the existing envelope for the existing
conditions of the existing building and the ASHRAE Min for the new building.
But it comes down to whether EA Credit 1 follows the new building % or the
existing building %. it is a 2 point difference that could effect
strategies for saving energy later in the design.

Rob

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You use the existing building criteria for % and points in LEED if your
existing portion is greater than half of the whole project sq.ft. (existing
+ addition).

Jorge E. Torres Coto

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The CaGBC allows using a pro-rated point scale based on the relative floor areas of new and existing. Not sure if this is the same for USGBC.

Kyle

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We have always used a pro-rated point scale based on floor areas as Kyle
describes for USGBC and it has never been disputed.

Thanks,

Matthew Larson, LEED AP BD+C

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We have a building that is going to be under renovation of interior and mechanical and lighting. The building has an new addition that was not certified as LEED building and not part of the project. Any ideas if we can do Commercial Interior without including the addition?

Thanks.

EXCELLENCE BEYOND EXPECTATIONS

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We have always used a pro-rated point scale based on floor areas as Kyle
describes for USGBC and it has never been disputed.

Thanks,

Matthew Larson, LEED AP BD+C

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We have always used a pro-rated point scale based on floor areas as Kyle
describes for USGBC and it has never been disputed.

Thanks,

Matthew Larson, LEED AP BD+C

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The current LEED template includes an entry for ?% new construction.?

If the template is as nifty as I would like to believe, it could scale the percentage thresh-holds to allocate points based on a pro-rated basis.

Anyone validate this?

Aaron Dahlstrom , PE, LEED? AP

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You are correct ? I just did a v2009 submission and the template did scale based on the percent renovated to addition. I have 7 points with 23.6% energy cost savings with 72% new, 28% renovation.

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Rob,
Its not a unique situation ? we run into this all the time. You should probably use LEED NC.

In the EAc1 template you can fill out percentages for new construction and for existing building (see below) and the calculation template prorates it.

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Vikram Sami, LEED AP BD+C

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