• Deck Supports: Fixed or adjustable height pedestals are the fundamental support system for outdoor decks and have become recognized as one of the most labor- and cost-efficient methods of creating a level deck over a moderately sloped surface. High-density polypropylene plastic that is 100 percent recyclable is a common material used to manufacture the deck supports. This makes them impervious to water, mold, and freeze-thaw cycles. Their adjustability offers tremendous design flexibility compared to traditional deck building materials and methods. Using a gravity system, the deck supports do not penetrate but rather protect roofing and waterproofing membranes thus causing no damage or harm to the surface below. The pedestals can be used to elevate the deck surface to meet the threshold, therefore providing an even and level transition from one space to another. This allows easy access for patrons with different levels of mobility. The location of the pedestals is typically based on a modular layout that follows the size of the material used on the deck surface. Commonly, this is a 2-foot-by-2-foot square grid, although many other sizes can be accommodated.
• Deck Surfaces: The versatility of adjustable pedestal deck support systems means that they can be used to elevate a variety of decking surface materials. The common options include pavers made from concrete or stone, such as granite or travertine. Similarly, structural porcelain tiles, fiberglass grating, composite materials, or conventional wood decking systems can be used in a grid pattern to meet different design requirements. Typically, a galvanized steel paver tray is adhered to the back of structural porcelain pavers or other materials prone to breakage to provide impact resilience and additional strength. The paver trays are available in a variety of standard sizes, compatible with large format ceramic tile sizes, and allow accommodation for thicknesses of 2 cm. With or without a support tray, the deck surface materials can be removed during building use for routine maintenance, repairs to the roof, or to gain access to other systems. If a lighter-weight surface material is preferred or needed, then wood tiles are a good alternative weighing only one-third as much as concrete tiles.
• Site Furnishings: Manufacturers of pedestal deck systems also offer coordinated, modular elements that are designed to integrate with their deck systems while giving the architect complete design flexibility. Modular wood or aluminum cubes are available with an array of design options to incorporate seating, storage, and planters. Such cubes are available with a polyurethane lining and drainage holes to host plant life. At other times of the year, the cubes can be repurposed for seating and storage of seasonal items (i.e., cushions and pillows) by placing a manufactured hardwood top on the cube. There are a variety of sizes and color choices available.

Overall, complete, coordinated, modular deck systems as described here, can be designed and specified to create attractive, durable, and sustainable outdoor spaces.

Planter and Trellis Project Example

Photo courtesy of Tournesol Siteworks

Project: The Gathering Place
Location: Denver, Colorado
Architect: Johnson Fain

The Project: There is a place of hope in the heart of Denver directly addressing the needs of community members experiencing the consequences of poverty and homelessness. The Gathering Place is a remarkable organization that focuses on providing essential resources and services to women and children in need. Among its innovative approaches to fostering community well-being and self-reliance, is its rooftop garden, an inspiring testament to sustainable urban agriculture.

The Garden Design: In 2007, large planters with trellises were installed along sections of the rooftop perimeter. The trellises are mounted between posts using clips that provide a concealed attachment and support flourishing vegetation, including eggplants, string beans, and plump tomatoes. The rooftop garden offers more than delicious seasonal veggies; it is a healing space and an opportunity to learn sustainable practices for the community it serves. This rooftop garden is an excellent example of how urban spaces can be transformed to serve the greater good, by demonstrating how sustainability and compassion can make a profound difference in people's lives.

SPECIFYING VEGETATION FOR LIVING WALLS

The benefits of living walls are contingent upon keeping the plants or vines alive and thriving. When there is confusion between an artificial green wall and an actual living wall, the design and specifications may not provide living plants or address other necessary components such as irrigation and proper orientation for adequate sun exposure. Coordination of the design among the different disciplines and trades is needed to meet project goals or building owner expectations. Since plants are living, everyone must recognize that working with nature is necessary to reap the benefits of biophilic design. Therefore, consider all the following in the design, planning, installation, and maintenance phases of a living green façade or other living feature:

• Sun Exposure: At the outset, it is important to remember that the sun orientation for the plants is key to their success. Different orientations or levels of sun exposure or shade may require different plant or vine selections.
• Seasons of the Year: It is important that everyone understands the seasonal quality of the vines or plants being used in a design. Some plants may change colors in the fall or go dormant in the winter in certain climate zones. Therefore, managing owner expectations for off season appearances can make a big difference in user satisfaction.
• Irrigation: Plants and vines need water to grow, so an irrigation system needs to be part of the design. Keep in mind that some irrigation systems that introduce fertilizer may need a back flow prevention mechanism to prevent the fertilizer from getting into the main plumbing system.
• Soil: Healthy soil will be needed for the proper growth of the vines. The volume of soil will depend on the type of vines and their intended growth. The soil is incorporated at grade or in planters.
• Plant Species: Living green walls and other trellis-based living structures can be utilized with various plant material selections. In general, twining vines such as jasmine, clematis and honeysuckle work best. Vines that attach with adhesive suckers such as English Ivy, Boston Ivy, and Creeping Fig should NOT be used for wall-mounted applications as these vines will attach to the wall in addition to the trellis panels. It is best to consult with a trained landscape specialist to determine the species most likely to be successful for a particular project.
• Building Connection: Attaching the trellis system to a building wall requires proper detailing of the connections. For example, some wall types may need blocking to attach a living wall trellis system.
• Maintenance: Maintenance is clearly vital to keep vines alive. It will begin the day that the vines are planted. Hence, the building owner should be clearly advised on how to properly maintain the plants and should have a maintenance plan in place to ensure the project’s success.

A fully functional system can be achieved by addressing the aforementioned points in the design and specification stage.

CONCLUSION

Outdoor spaces benefit from good landscape design but require attention to detail. When carried out and executed properly, they can be key in achieving project sustainability goals and creating a welcoming place for people. By understanding some of the different options for horizontal, vertical, and feature related items discussed in this course, design professionals can achieve better results.