The role of a landscape architect in sustainable home construction
Sustainable construction is not only important for major companies, but for homeowners as well. This method of thinking has lead to the creation of many green home certification systems.
One of most well-known is the USGBC (United States Green Building Council) LEED V3 (Leadership in Energy and Environmental Design version three) certification system which was discussed recently at the 2010 meeting of the Kentucky chapter of the American Society of Landscape Architects Conference held in Shaker Village.
At the conference, Scott Southall, CDP Engineers vice president and leading landscape design expert, gave a presentation on LEED V3 for major companies. However, the sustainability ideas he mentioned can be used in home design as well.
“Historically, landscape architects have balanced the relationship between the built environment and the natural landscape,” said Southall, a leading landscape design expert. “However, in today’s world is a balanced landscape enough? Landscape architects can be the vanguard of this changing paradigm in community development.”
The LEED V3 certification system includes ideas for being more water efficient, choosing the most ecologically-friendly building materials, and incorporating a variety of energy saving systems, which can all be applied to home construction and renovation projects as well.
Water efficiency involves the incorporation of many different sustainability projects that build off one another. A bio-retention system built underneath the property will collect gray water, or rain water to use in irrigation systems for gardening and in toilets, while also preventing runoff during storms and floods. Having more plants instead of concrete in the yard will create surface area resulting in quicker water absorption and the system will store the water until it is needed.
The use of permeable pavement or clay brick instead of solid concrete in a driveway or patio will make it easier for water to drain into the soil as well. These products will also reduce pollution by releasing less CO2 emissions than concrete production. The best choice for a pavement is a lightly colored option that will reflect sunlight rather than absorb it. This will help to reduce the ‘heat island effect’ responsible for raising the temperature of the property and which creates more dependence on an air conditioning unit for in home comfort. At night the moonlight reflects which eliminates the need for outdoor light fixtures and reduces the need for street lighting as well.
A green wall or a roof top garden can also help control building temperature by eliminating the concrete’s exposure to the sun. The home can be positioned on the property with the majority of sunlight hitting the back side, where the green wall will be located, reducing energy cost, and adding to comfort while serving as an aesthetically pleasing backdrop for a patio garden. The roof top garden will stop sun light from being absorbed by the roof and can also become a popular gathering area for recreational activities.
“Homeowners will be leading in the efforts to create a greener society,” said Southall. “It becomes significant for a landscape architect to be involved upfront, from the beginning, along with the design team so that well informed decisions can be made concerning all areas of construction and function of the building created."
Involving a landscape architect in the choice of wood used to complete the project will have a large impact on the end product’s overall sustainability. A renewable wood choice, such as bamboo, or a product that is FSC (Forest Stewardship Council) certified, will guarantee that it was legally harvested in an eco-friendly manner. The FSC trademark symbol is stamped on all wood that is certified as being produced in an eco-friendly manner. Some woods read FSC mixed, meaning the production line is not fully traceable, but as far as they know, it was produced in a sustainable manner. A consumer should look for these stamps when purchasing materials.
The house’s location on the property should also be considered to allow for the most optimal use of natural lighting in the home. Window and glass wall placement can be used to lower lighting costs and this will also help improve the health of the family living in the home based on USGBC studies.
Other ways to lower energy dependency are to collect and store power with wind spirals (or turbines depending on the amount of land available) and solar panels, and to use Energy Star Appliances when possible.
The early involvement of a landscape architect in design plans can allow future green projects to be built into the house as the homeowner’s budget allows. Waiting to involve the landscape architect can be more costly and the desired changes made may not fit with the overall design of the house. The architect will also be aware of EPA building guidelines as well as LEED project suggestions to create the best end product possible.
The LEED Neighborhood Development (LEED ND) program offers a rating system to help homeowners focus on sustainability in their community. Major point areas include: intelligent location & linkage to surroundings, the use of neighborhood pattern & design, green construction & technology and the innovation & design process.
While the LEED system is great for getting sustainability project ideas, some landscape architects are not completely satisfied with the rating scale currently in use.
“Changes need to be made in the point value system to promote building preservation over demolition,” said Bill Weyland, managing director of City Properties Group in Louisville, in a subsequent presentation. “The best way to be environmentally sustainable is to leave the existing structure instead of tearing it down to rebuild it with new materials and LEED should recognize this in their program.”