According to the National Research Council of Canada:
LEED buildings used 18-39% less energy per floor area than their conventional counterparts. However, 28-35% of LEED buildings used more energy than their conventional counterparts.
I am sure that LEED building standards are favored by the construction and contractor lobbies as such standards raisethe cost of construction. By the way, even if LEED buildings use 20% less energy than their conventional counterparts, that in no way decides whether it makes sense to build them. If instead I told this to you:
“Wintercow produced buildings spend 18%-39% less money on ornamental doorknobs than his conventional counterparts” would it become a matter of public policy to erect more buildings with the aid of Wintercow?
Who can argue against wasting resources? (Oops, I forgot about windmills, ethanol, and the Volt.) The fourth Little Pig should be free to build his house with foamwall panels if that makes him happier, and the Big Bad Wolf should mind his own business.