Choosing Appropriate Materials for Net Zero Buildings
When prominent people in building design and innovation showcase the energy savings of their Net Zero buildings, they raise public awareness and enthusiasm. For many, Net Zero in a functioning building looks easy; however, the task of incorporating all the design and physical elements is a complex undertaking. Homebuilders who want to participate in the growing net-zero market, need to appreciate this complexity for their project to succeed.
When a building achieves Net Zero certification, it means that building energy production equals building energy consumption for one year. For homebuilders aiming for net zero certification, this entails working with manufacturers who design materials that integrate and work well with the other elements.
Moreover, the success of green buildings depends on teamwork by everyone involved: contractors, architects, designers, engineers, material manufacturers and owners. In a study entitled “Zero Net Energy Building Controls: Characteristics, Energy Impacts and Lessons” conducted by the Continental Automated Buildings Association, researchers found that net zero buildings have some control problems stemming from installation issues and the process to ‘get it right’.
According to the association’s communications director, their report found that both the operators and the design team recognize that useful solutions require the installing controls contractor and building operator to have more active involvement in early design, commissioning and after occupancy. For example, most design firms believe that HVAC, lighting and plugs each have a more than 15% bearing on energy savings and having effective control of these systems means the building owner will achieve his energy objectives.
The journey to a successful net zero project begins with site selection and orientation, positioning the building for optimal lighting and reduction of electric and heating costs. While the goal is to maximize solar gain in the winter, it’s also necessary to block solar gain in the warmer months.
Builders will want to focus on choosing products or systems that enhance the natural light coming into a building, such as vision glass, skylights, translucent openings and clerestory windows or products or systems that help manage solar gain like shading systems, louvers and outriggers, external sunshades, electrochromic glass or coated glazing.
The next step is to make sure that the building envelope is well-insulated and high-performing, retaining all the cold-treated air in the warm season and heat-treated air in cold weather.
Treated air of any sort represents energy consumption.
For homebuilders, designers and architects, this means incorporating a system or products that help make up the overall envelope and enhance envelope performance. This can include thermal-performing glazing, air and moisture barriers, cladding systems, insulation, roofing-related materials and products and operable windows for natural ventilation.
The air and moisture barrier in a net zero building is a critical part of the building envelope that is frequently a source of problems. The first problem is the selection of the wrong barrier that does not meet the performance requirements of net zero construction.
The second and more frequent problem involves installation issues. Many barriers require a lot of attention to detail on the part of the installer with seams and fastening systems. They also require careful inspection before the cladding can be applied. If left exposed some of these barriers are easily damaged by wind, weather and other contractors on the job site.
These barriers then have to be repaired.
The final issue with air and moisture barriers in net zero houses is the importance of having the right perm rating. This ensures that any water vapor that builds up in the house can easily escape.
A fully adhered high performance air and moisture barrier like DELTA®-VENT SA solves all three of these potential problems.
Next, the builder, along with systems operators assess different mechanical, electrical and plumbing (MEP) systems that heat and cool the building in energy-efficient ways, such as geothermal heat pumps to cool, heat and provide hot water. System operators’ involvement and training are essential to the long-term success of the net zero building.
Builders should select lighting products that offer more energy-efficient electric illumination, control or dim lights, or activate dimming settings in concert with daylight measures. As to the HVAC system, they should choose products or systems that contribute to high-performance passive cooling and heating.
Products or systems that promote water conservation measures are important components of the net-zero construction market. These include low-flow fixtures, roof gardens, cisterns and systems or products that harvest, collect or augment rainwater retention.
After builders have set up the basic systems for minimizing building energy consumption, they should evaluate options, such as PV-related products, wind power products and regenerative drive elevators to offset energy consumption.
Finally, homebuilders should showcase their products to clients and the public. When customers experience working examples of energy-saving products, they are more likely to consider incorporating the product or system into their own project.
Dörken delivers innovative, high-performance air and moisture barriers for commercial and residential construction sold under the DELTA® brand name. A North American manufacturer based out of Beamsville, Ontario, Dörken Products, Inc. is a subsidiary of Ewald Dörken AG, a leading European developer and manufacturer of waterproofing and drainage products sold worldwide. Dörken is known for delivering premium products while providing educational programs and full technical support. For more information, call 1-888-4DELTA4 (433-5824) or visit www.dorken.com.