Zero Carbon Building Process

Green building can give part of the answer for zero carbon emissions from the building sector. But what would a truly zero carbon building look like that had no carbon impact at all from construction, through occupancy through demolition?

First, the site would have to be selected so that the occupants of the building could access essential services without a car. Food would preferably be locally grown using zero carbon farming techniques. Water, wastewater and solid waste systems would similarly be zero net carbon, and would use appropriate levels of food waste recycling, energy harvest and decentralized processing such as graywater systems and rainwater harvest. Location of the site should also enable easy access to mass transportation.

Site preparation would be done using either manual labor for excavation, or machinery powered by biodiesel. All materials would be brought to the site by vehicles powered by either biofuel or electricity. Concrete would only be used in the foundation if it was manufactured using renewable energy, and the carbon dioxide from cement production was sequestered.

All power tools used in construction would be powered by energy generated onsite, either by solar or by generators powered by biofuel. The grid electricity could only be used if came from renewable sources.

The building materials themselves would either be locally manufactured, from sustainably forested lumber, milled using renewably-powered sawmills, or would be recycled. Locally grown wood, recycled metal and glass and local clays or cob could be used.

The building would be constructed so that it could be expected to last for 50-100 years, and that if it needed to be demolished, the materials could all be reused, or returned to the earth. No construction or demolition debris would be landfilled or would need transportation from the site.

The building itself would be a high performance envelope, constructed to maximize the use of solar energy for heating, and natural ventilation for cooling. All southern windows would have seasonal shading geometry, so they would be shaded in summer, but not in winter. Green building techniques would be used throughout.

This is an outline of the kinds of considerations that would have to go into a "true" zero carbon building project. Although not a complete picture, this gives an idea of the complexity of the problem.