Archives for August 2012

Who really pays for LEED certification?

Obtaining LEED certification costs a lot of time and money.  The resources required are not limitless and are generally diverted from other uses, though that seems impolite to discuss when pursuing sustainability.

But LEED certification does not, of course, add to a property’s sustainability.  Rather it confirms, or certifies, that objective sustainable criteria have been met.   If anything, the high costs of LEED certification divert funds that may be otherwise be spent on sustainable materials or systems.

In the end, the high cost of LEED ultimately comes from somewhere….or someone. 

[Read more…]

The Greenest Building is the one that is already built

This elegant phrase by architect Carl Elefante is bolstered by an important new study, The Greenest Building:  Quantifying the Environmental Value of Building Reuse.

National Real Estate Investor opines that the study, commissioned by the National Trust for Historic Preservation’s Preservation Green Lab, empirically shows, “It is unequivocally greener to retrofit an old building than construct a new building, no matter how many high-tech bells and whistles are in the new construction.”

[Read more…]

Convective Heat Loss, a sneaky villian

Strategies to increase building energy efficiency typically focus on increased efficiency of the HVAC system and increased thermal resistance of the envelope and fenestration. An oft- overlooked, but vital, path to efficiency is reduction of air-leakage.

Heat transfer in buildings occurs in three forms: conduction, convection and radiation. Of these, conduction and convection transfer most of the heat. Conduction occurs when one body transfers its heat to another with which it is in contact–in this case, the transfer between interior and exterior air. Convection occurs when a heated body physically transports itself to another location. In this case air physically moving through leaks in the wall. Thermal insulation prevents conduction but does little to prevent convective heat losses.

[Read more…]