Building Science


Net zero energy buildings are what we do. Structures that are “Net Zero” have an energy generation that equals or exceeds their annual consumption.

Passive House (aka Passivhaus) is the most stringent and innovative design standard for high performance building. Developed by a German Physicist, it is known world-wide as the highest bar for energy efficiency, surpassing LEED certification in various standards. It’s design focus utilizes improving on building air tightness, heating and cooling energy demand, and overall energy demand. We certify our projects with US based Passive House Institute US (PHIUS) in order to achieve world class quality in energy performance.

LEED standards broad sustainability goals provide a design complement to the achievement of net zero energy building.

Metro Green homes are built with super insulating building envelopes in conjuncture with a passive solar methodology to decrease the usage and dependency on unsustainable energy sources. These techniques aim to reduce heating, cooling, and lighting loads through climate-responsive design and conservation practices.


The above approach creates the most efficient barrier to minimize thermal transfer (heat loss/gain) and air leakage between the interior of a structure and the outdoor environment. Using smart orientations of high quality windows and doors, specific absorbing building materials, and energy recovering ventilation systems that supply filtered fresh air allows our homes’ to harness the sun’s energy and fulfill their own heating and lighting requirements. As heating and cooling accounts for 50-70% of the energy used in the average American home (U.S. Department of Energy 2002), these design principle greatly minimizes the use of polluting external sources like oil, gas, etc.

In fact, Passive House buildings routinely reduce heating energy by 90%.


High performance building is not just about making our carbon footprint smaller…From our perspective, it’s the smartest way to build and provide a sustainable life.  These designs not only deliver efficiency, but create buildings that are more durable, comfortable, and healthy. The diagrams below show the US Department of Energy’s assessment of how Passive House buildings perform compared to ENERGY STAR and conventional buildings. Passive House buildings significantly outperform the others on all four measures.


All images sourced from Hammer & Hand