AUSTIN, Texas--Concern about climate change has prompted the Lady Bird Johnson Wildflower Center and Mithun, a leading sustainable design company, to develop a web-based tool for calculating and reducing greenhouse gas emissions.Buildings are a major producer of carbon dioxide (CO2), and other greenhouse gases-48 percent of total greenhouse gas emissions, according to the Environmental and Energy Study Institute. The creation of materials used in buildings and the construction process itself also release carbon dioxide into the atmosphere. As concerns about global warming increase, there is more interest in reducing the “carbon footprint” or total emissions from construction projects. A goal of the City of Austin is to provide mechanisms for all businesses and individuals to reduce their carbon footprint to zero.

The new carbon calculator is an important tool because it allows building owners, designers, developers and contractors to compute the total amount of carbon dioxide that will be released by a building project as result of the selection of building materials and the construction process. It also determines the impact of green space and landscaped areas on production of greenhouse gases. The calculator is known as BuildCarbonNeutral and is available at www.buildcarbonneutral.org.

Similar tools have been available, but have only produced information about the carbon dioxide released during day to day operation of a building.

Plants and landscapes play an important role in reducing greenhouse gas emissions because plants use carbon dioxide as a nutrient. Plants pull CO2 from the air and “sequester” or capture it in the soil where it is trapped-sometimes hundreds of years-rather than being released into the atmosphere where it contributes to global warming.

Existing calculators do not account for carbon held in plants and landscapes. The first version of BuildCarbonNeutral calculates the amount of carbon dioxide released when large natural landscapes, such as prairies and forests, are destroyed. Future versions will calculate the amount captured in smaller urban landscapes such as roadsides, lawns and gardens. Armed with this information, designers can engineer the entire site to reduce its carbon footprint.

“BuildCarbonNeutral is designed to improve with use,” says Bert Gregory, FAIA, Mithun’s president and CEO. “The calculator is based on our research into existing models combined with data sets culled from multiple series of construction cost estimates and ecological literature. Adding more data will increase its effectiveness. We welcome feedback to develop ideas and technology that will support growing efforts to reduce global warming.”

The Wildflower Center and Mithun encourage three steps to decrease the environmental from construction: Reduce, renew and offset. That means finding ways to reduce the emissions from both the building and the construction process, maximizing the use of renewable energy and finding offsets for the gases released, such as carbon-absorbing landscapes.

“Because native plants can be so important in combating climate change, we have a number of projects underway that help the construction industry create sustainable sites,” said Mark Simmons, Wildflower Center ecologist. “We started working with Mithun in 2006 as part of our national initiative to promote best practices for sustainable development.”

The calculator is simple to use. It asks for square foot measurements of a building’s size, the project’s eco-region and the amount and type of landscape created, restored or removed.

About the Lady Bird Johnson Wildflower Center The Lady Bird Johnson Wildflower Center at The University of Texas at Austin is dedicated to increasing the sustainable use and conservation of native plants and landscapes. Founded by former first lady, Lady Bird Johnson, in 1982, the Wildflower Center maintains an extensive native plant botanic garden and offers professional and adult education programming. The Wildflower Center also conducts research on landscape restoration and plant conservation at its 279-acre site, promoting the role of native plants and plant communities in addressing ecological problems. Recent research initiatives focus on native turf grasses, use of native plants on green roofs, and evaluation of carbon sequestration by native plants in urban landscapes.

About Mithun Mithun is a national leader and advocate for sustainable design and urbanism, recognized for setting new standards in the development of resource-efficient structures and communities. The firm’s innovative and collaborative spirit encompasses architecture, urban planning, interior design and landscape architecture. Integrating nature, technology and design, Mithun creates vibrant mixes of commercial, residential and public spaces for future generations. Awards include four AIA COTE Top Ten Green Projects, two ASLA national honor awards, and the AIA national honor award for regional and urban design for Lloyd Crossing, a 35-block inner-city neighborhood plan that mimics the carbon footprint and natural systems of a pristine forest.