The Crossings Sustainable Building Summary 2003

Site Sustainability

Habitat and Landscape Preservation — The Crossings is located on 210 acres of beautiful, yet fragile, Texas Hill Country landscape, with views of nearby Lake Travis. The site includes habitat for the endangered Golden Cheeked Warbler. In order to limit negative impacts on the site and its habitat, all construction on the site is limited to 34 acres, with the balance of the site undisturbed and protected through an agreement with the U.S. Fish and Wildlife Service. The layout of the buildings and other facilities was made only after an extensive process of inventorying evaluating site conditions and resources. Most hardwood trees, the larger ash junipers, native grasses, and significant rock formations were preserved. Within the 34 acres where construction activities are occurring, significant efforts have been made to reduce site impacts to only the immediate area of building construction.

Landscaping — The Crossings’ landscape plan seeks to cause the least possible disturbance to the site, while enhancing the visitors’ enjoyment of and connection to the natural beauty and richness of the land. The intent is not only to promote an appreciation of this particular piece of land, but also to encourage a greater appreciation of nature and the outdoors in general.

Avoiding Light Pollution — In order to be a good neighbor, outdoor lighting at the Crossings is used only where necessary and is designed to minimize the amount of light leaving the site.

Minimize Paving Impacts — Paving and other impervious surfaces are limited to the least extent possible at the Crossings. In order to reduce water runoff and increase groundwater recharge, where paving was not necessary alternative methods have been employed such as an unpaved overflow parking area or open grid paving for a road that will be infrequently used. Roads and walkways that are paved are constructed using light colored concrete, thereby reducing the buildup of heat. Existing vegetation has been preserved as much as possible to shade all new pathways, roads, and structures, thereby minimizing heat buildup and energy consumption.

Energy, Atmosphere, and Global Climate Change

A wide range of strategies have been used to minimize the Crossings’ energy consumption, air pollution, and its impact on global climate change.

Perhaps the foremost goal in this regard is the use of passive strategies (free of mechanical or electrical systems that require the combustion of fossil fuels) to maximize human comfort. These strategies include maximizing natural ventilation and strategic placement of windows to admit light and views without admitting unwanted heat or cold.
All significant building systems (e.g., lighting, heating and cooling, water heating) have been designed with energy efficiency as a priority. Wherever possible fluorescent lighting has been chosen to light public areas due to its low energy consumption and efficiency. In the meeting rooms, a combination of fluorescent and incandescent lighting was installed to give the optimum lighting for the space, and to meet the specific requirements of faculty.
All buildings are equipped with high performance windows that reduce the transmission of unwanted heat and cold.
All of the walls and roofs are highly insulated to reduce heating and cooling loads and save energy.
The Crossing will promote a “walking environment.” Within the site, scenic pathways connect all significant facilities, thereby encouraging walking as a means of getting around. To the extent that vehicles are used at all, much of the movement of people and goods will be accomplished using battery powered golf carts, thereby reducing noise and improving air quality.

Water Conservation

As is increasingly the case in all areas of the world, water has become a precious commodity in Central Texas, and the Crossings has endeavored to be extremely mindful of water consumption. The Crossings employs a number of water conservation strategies:

With the exception of two small, more highly manicured areas, all site landscaping will be done using xeriscape methods and using drought tolerant plants. Most of the plants will be native or adapted to Central Texas, which not only enables them to thrive with little irrigation but makes them resistant to disease and pests and consequently minimizes the need for fertilizer and pesticides.
Much of the rainwater that falls on the roofs of buildings will be collected and stored for use in landscape irrigation.
Effluent from the on site waste treatment plant will be used for irrigation.
All plumbing fixtures (toilets, urinals, lavatories, showers, etc.) are “low flow” fixtures that minimize water consumption.

Resource Conservation

Recycled Materials — In order to reduce the consumption of non-renewable natural resources, many of the building materials used at the Crossings contain recycled content. The building materials with recycled content include:

Concrete – All of the structural concrete used at the Crossings contains fly ash. This material is a byproduct of coal-burning electric generation, and if not incorporated into concrete, is generally treated as a waste material and disposed in landfills.
Wood-Plastic Decking – Many of the outdoor decks at the Crossings are fabricated using wood/plastic decking, which contains no virgin wood. Instead, the decking is manufactured using reclaimed plastic products (primarily returned grocery sacks, pallet wrap, or stretch film) and waste wood (primarily off-cuts and sawdust from furniture making and ground up oak pallets). TREX decking.
Fiber-Cement Siding - Many of the buildings at the Crossings have fiber-cement exterior siding, which is manufactured as a composite of primarily ground up wood chips and Portland cement. While these products do not contain recycled materials, they reduce wood consumption by avoiding the use of true wood board siding fabricated from mature trees. The fiber-cement siding also provides a more durable, lower-maintenance product than the wood siding. HARDI-BOARD and HARDI-PLANK.
Wall and Roof Insulation – The wall and roof insulation used at the Crossings has a minimum 30% post-consumer recycled content.
Acoustical Treatment – The acoustical material used as a floor underlayment is made using 100% post-consumer recycled waste paper with no asbestos or formaldehyde additives.
Gypsum Wall Board – Painted gypsum wall board (sheetrock) is the most common interior wall finish at the Crossings, and all of the wallboard contains a minimum 95% recycled content.
Acoustical Ceilings – The acoustical ceiling tiles installed at the Crossings have a recycled content varying from 37-69%.

Rapidly Renewable Materials — In addition to reducing the consumption of natural resources through the use of materials containing recycled content, the Crossings also employs materials derived from rapidly renewing resources. These include flooring made from bamboo (a rapidly growing and renewable plant material) and from linoleum, which is manufactured using cork (a renewable resource from the bark of cork trees) and linseed oil (an agriculturally derived product).

Durable Building Materials – Through the use of very durable building materials – fiber cement siding, exposed concrete floors, stucco, masonry, and metal roofs – the Crossings will reduce maintenance requirements, and consequently minimize energy, chemical, and resource consumption.

Local Materials — The use of locally- or regionally-sourced materials, such as stone quarried in the Central Texas region, reduces energy consumed in transporting building materials long distances.

Storage and Collection of Recyclables — Once in operation, the Crossings will employ an integrated system of collection, storage, and pickup for materials to be recycled. Recycled products will include corrugated cardboard, paper, glass, plastics, and metals. In addition, it is anticipated that 100% of the food waste will be removed off-site for composting.

Human Health and Indoor Air Quality

Low Emission Building Materials — The prudent selection of building materials at the Crossings will protect the health of visitors (and construction workers) by using building materials that have no or low emissions of harmful gasses such as formaldehyde and volatile organic compounds (VOCs).

Except where unavoidable because of performance requirements, all of the paints and other finishes used at the Crossings are no- or low-VOC.
All of the carpet used at the Crossings meets or exceeds the Carpet and Rug Institute’s Green Label Indoor Air Quality Test Program, which assures that the products will not pose a threat to good indoor air quality and human health.
Medium Density Fiberboard – Where wood trim and cabinetry products are made using medium density fiberboard (MDF), which is a common wood product for such applications, the MDF is formaldehyde-free, thereby protecting indoor air quality.
Oriented Strand Board – A number of the sheet wood products used for wall or roof decking are made of oriented strand board (OSB), which is a composite of wood chips and adhesives. OSB allows an efficient use of wood and protects forests by reduces the harvesting of older growth trees. Unlike some wood board products, OSB is fabricated without the use of urea formaldehyde resins, which would post a threat to indoor air quality.

Daylight and Views — Virtually all of the occupied rooms at the Crossings are supplied with generous amounts of daylight through the strategic placement of windows and skylights. Further, the careful placement of windows allows visitors to enjoy the beautiful natural setting even while inside the buildings.