Final Performance Report
Two Trails, Inc. continues to work closely with Sun West Custom Homes to ensure energy efficiency and design innovation in The New American Home 2020. The progress and proposed efficiency elements are displayed below.
Unvented and air sealed attic with a combination of Demilec Sealection®500, open-cell, polyurethane foam insulation and Hy-Fi reflective insulation for a total insulation value of R-48
Western Windows and patio doors with low-e coating, argon gas fill, with an average U-Factor 0.38 and SHGC of 0.24, limits solar heat gain and optimizes air tightness
Exterior walls insulated using Demilec Sealection®500, open-cell, polyurethane foam insulation and Hy-Fi Hybrid Wall & Ceiling reflective insulation from Fi-Foil for a total insulation value of R-23
Large overhangs to aid in protecting the home from the harsh Nevada sun
Light colored exterior to assist in reflecting the sun
Mitsubishi’s Ducted HVAC system provided space conditioning, with an average efficiency of 16.73 SEER
Variable speed compressors in outdoor heat pump units adds efficiency and quietness
Lifebreath’s Energy Recovery Ventilators (HRVs) quietly provides fresh air while reducing the loads on the HVAC system
Mechanical ventilation provided by Panasonic
Space conditioning system located entirely within the conditioned space
Rinnai ENERGY STAR®-rated tankless water heaters with an efficiency (UEF) of 0.93
Insulated hot water lines utilized throughout the project to reduce heat loss
100% energy-efficient LED lighting for all interior and exterior lighting
LG ENERGY STAR®-rated appliances
ENERGY STAR®-rated variable speed pool pumps
19.8 kW system using 60 - LG’s NeON2 V5 340-watt solar panels with Enphase IQ 7+ Microinverters.
Energy Efficiency and Innovation
As one of the NAHB’s official show homes, The New American Home (TNAH) 2020 is a symbol of energy efficiency and innovation. The home exhibits innovative products from manufacturers all over the world.
TNAH 2020 is designed to exceed the requirements for certification to the Emerald level of the National Green Building Standard™. Its energy-efficient features can be used in homes in a hot climate at any price point with similar energy savings. The home is projected to be awarded the EPA ENERGY STAR® for Homes, DOE’s Zero Energy Ready Home, as well as the EPA’s Indoor airPLUS certifications.
Two Trails, Inc. worked closely with Sun West Custom Homes to ensure energy efficiency and innovation in TNAH 2020. Without the solar array, this home has a projected HERS Index of 49, or 51% more efficient than the average new code-built home. With the 19.8 kW solar array, this home has a projected HERS Index of -16, or 116% more efficient than the average new code-built home. TNAH 2020 tested envelope leakage rate of 2.35 ACH(50) further contributed to the extremely low projected HERS Index. At this level of energy efficiency, the home is projected to provide $3995 in annual energy savings to the homeowners
In addition to energy savings, this home is designed to achieve a 72.05% reduction in water use. This remarkable water use reduction is made possible using low-flow water fixtures, natural indigenous landscaping, and a high-efficient drip irrigation system. Water saving features include:
Kohler low-flow, EPA WaterSense certified 1.2 GPM lavatory faucets and an average of 1.10 GPF toilets provides the indoor water use reduction
High-efficient driplines, natural indigenous landscaping and irrigation controllers contributed to the outdoor water use reduction
Indoor Environmental Quality Features
Indoor Environmental Quality encompasses the conditions inside a home, and their effects on residents. The New American Home 2020 incorporates innovative strategies, creating an indoor environmental quality that enhance the lives of homeowners, protects occupants’ health, and improves quality of life. Indoor Environmental Quality strategies include:
Sherwin Williams Low-VOC paints and finishes and low-VOC interior adhesives and sealants
MERV 13 space conditioning air filters
HVAC ducts sealed during construction to prevent pollutants from construction activities from entering the system
Whole Building ventilation system configured to allow the correct amount of fresh air into the home
Eco-Friendly cabinets – Formaldehyde free and material certified by the Forest Stewardship Council
Systems Engineering Approach
The systems-engineering approach unites segments of the building industry that have previously worked independently of one another. The concept is simple: systems-engineering can make America’s homes cost effective to build or retrofit and energy efficient to live in. Energy consumption of new houses can be reduced by as much as 40% with little or no impact on the cost of construction.
To reach this goal, the Sun West Custom Homes team is working with their building partners to produce a home that incorporates energy and material saving strategies from design through construction. First, the team analyzed and selected cost-effective strategies for improving home performance. Next, the team evaluated design, business, and construction practices within individual partnerships to identify cost savings. Cost savings could then be reinvested to improve energy performance and product quality. For example, a design that incorporates new techniques for tightening the building envelope enabled Sun West Custom Homes to install smaller, less expensive heating and cooling systems. The savings generated in this process can then be reinvested in other high-performance features to further reduce energy use. Proving the efficiency of the system-engineering approach to construction, this home’s registered HERS Index, without the use of a Photovoltaic system is 49, which is 51% more efficient than the construction of the average new home, and with the 19.80 kW solar system, a projected HERS Index of -16!
The “pilot” or “test” home is the field application of solution design. The team assisted Sun West Custom Homes in designing TNAH 2020 in accordance to strategic design, modeling to maximize building efficiency of each system and directed the team to increase efficiency through cost effective decisions. Before additional houses are built, these changes are incorporated into the design. This process of analysis, field implementation, reanalysis, and design alteration facilitate ultimate home performance once a design or retrofit strategy is ready for use in production or community-scale housing.
Understanding the interaction between each component in the home is paramount to the systems-engineering approach. Throughout design and construction, the relationship between building site, envelope, mechanical systems, and other factors is carefully considered. Recognizing that features of one component can dramatically affect the performance of others enables the Sun West Custom Homes Building team to value-engineer energy-saving strategies at little or no extra cost.