IBS, The International Builders Show, is the largest yearly residential and light commercial construction tradeshow in the world. Typically more than 1400 construction manufacturers and suppliers showcase the latest and most in-demand products and services in the industry. Although I love seeing homebuilding products on the showroom floor of IBS, my very favorite part of the show is touring the 2 official idea houses they build every year — The New American Home 2020® (TNAH), and The New American Remodel™ (TNAR). You know I love a show home, especially one that’s been built with energy efficiency and quality construction in mind. We can get ideas for pretty decor almost anywhere, but it’s so much more valuable for us to look at examples of houses that are not only pretty, but well-built. High performance concept homes like The New American Home can give us ideas about material and methods that we can either use, or adapt for our own projects. Before we discuss the house specifically, let’s talk about the weather in Las Vegas, where the house was built, to see how it compares to where you will build. As you know, houses built in different climates might need to be constructed a bit differently. In Las Vegas, the summers are very hot and the winters are surprisingly cold. In January, the average high in Vegas is 58 degrees F and the average low is 34 degrees F. And in July, Vegas averages a sweltering 106 degrees F during the day and 74 at night. Las Vegas is dry, with little humidity and only about 4 inches of rain per year. It almost never snows. Let me take a quick pause right here so I can give a shout out to grggrs who left a 5 star rating and review in Apple Podcasts. Thank you for supporting me and the show by writing so many complimentary things for the whole world to see. I appreciate you. I also want to ask Christina Z, who sent me an email on Jan 19, to resubmit your email address. I think you may have mistyped the email because I tried twice to reply and both times my email came back with a message saying that the email address does not exist. Ok, let’s talk about the design and construction of the New American Home…. In addition to using some of the most cutting edge technologies and materials, the concept house has breathtaking, panoramic views of Las Vegas Strip and the surrounding foothills, so it made sense that its design incorporated many walls of windows and emphasized indoor-outdoor living. As I’ve told you before, blurring the lines between the inside and outside is a big trend in home design wherever new houses are being built, even if there isn’t a magnificent view. The New American home is a large, one-story house with just over 6400sq. ft. of living space, four bedrooms, five and a half bathrooms, and a two car garage. Because of all the windows, there is lots of natural light and it has wide open sightlines from one living space to another. The large great room opens up to the heated outdoor entertaining area. Soft contemporary is the style of the architecture and decor. I've been showing soft contemporary designs in several of my Instagram posts. It’s one of my favorite styles. Soft contemporary has sleek, clean lines like regular contemporary design, but the look is not as harsh or hard. Soft contemporary decor has a softer, warmer look because it has more curved lines, more wood and more texture as compared to typical contemporary decor. Alright, let’s get into how the New American Home was actually constructed. This house has a tight building envelope, which most all energy efficient house will have. There is an air sealed attic that’s not vented to the outside, meaning it’s a conditioned space that has insulation and heated and cooled air coming into it. They used open-cell spray foam insulation in combination with a product called HY-Fi reflective insulation for a total insulation value of R-48. HY-Fi insulation is a hybrid insulation system that works together with other types of insulation like spray foam or fiberglass batts to increase thermal resistance and decrease heat loss. Using the HY-Fi hybrid insulation system reduces the amount of spray foam insulation required. Spray foam and HY Fi insulation were also used to insulate the walls of the home for a total R value of 23. The New American Home used Western Windows and patio doors with a low-e coating and argon gas between the window panes. The windows have an average U-Factor 0.38 and an Solar Heat Gain Coefficient (SHGC) of 0.24. Remember the lower the U factor of a window, the better, and in hot climates, you also want a low Solar Heat Gain Coefficient. The house also has large roof overhangs to protect against the harsh Nevada sun. Light colored exterior cladding was used to reflect instead of absorb the sun to help keep the house cooler. Phantom retractable outdoor screens were installed as another provision to keep heat from coming in through windows. Exterior screens are typically 7X more effective at reducing building heat gain as compared to interior shades. On the HVAC front… A variable speed heat pump was selected for its efficiency and quietness. Remember that heat pumps work well in warm climates. To learn more about heat pumps, you can listen to episode 44 called "What Exactly Is A Heat Pump?" Unlike a conventional single speed HVAC system that cycles on at 100% then completely off, a variable speed system runs at different speeds to precisely control the flow of heated or cooled air throughout your home. More precise control means a better balance of temperature and humidity and greater energy efficiency. Variable speed units use advanced technology to constantly monitor information from the HVAC system itself and from the environment so it can automatically make adjustments necessary to meet your comfort needs and thermostat settings. Put simply, a variable speed HVAC unit delivers the exact right amount of air for the right level of heating and cooling comfort. And as an added bonus, a variable speed unit gradually ramps up to full speed, eliminating the sudden, noisy blast of air that you typically hear with standard HVAC units. This makes a variable speed HVAC system very quiet. That also reduces stress on the system and gives the air conditioner more time to remove more humidity from the air, which typically makes the air more comfortable. Because the New American Home has a tight building envelope, it was important that it also include mechanical ventilation, which takes stale air out and brings fresh air in. They chose mechanical ventilation from Panasonic and Lifebreath’s Energy Recovery Ventilators (HRVs). The HVAC system was put in the conditioned space. Remember a conditioned space is one that is insulated and has heated or cooled air ducted to it. By putting the equipment in a conditioned space (a conditioned attic, for example), it won’t have the stress and inefficiencies that putting the systems in the extreme heat and the relative cold of the outdoors or in unconditioned attic. HVAC systems run more efficiently in a conditioned space, which saves on utility bills. Rinnai ENERGY STAR®-rated tankless water heaters were used and they Insulated hot water lines to reduce heat loss. The house is equipped with energy-efficient LED lighting for all interior and exterior lighting. They used LG ENERGY STAR®-rated appliances, and ENERGY STAR®-rated variable speed swimming pool pumps. LG was also the maker of the home’s solar panels. There is 60 panel system for a total of 19.8 kW. For reference the average 2000 sq ft US home uses approximately 32 Kw per day. TNAH was designed to exceed the requirements for certification to the Emerald level of the National Green Building Standard. And according the it’s website “Its energy-efficient features can be used in homes in a hot climate at any price point with similar energy savings". The home is on its way to being awarded certifications from the EPA ENERGY STAR® for Homes program, DOE’s Zero Energy Ready Home program, as well as the EPA’s Indoor airPLUS certification. Without the solar panels, this home has a projected HERS Index of 49. The HERS Index is a measure a home’s energy efficiency. The lower the HERS score, the better. 100 is the HERS index for the average code minimum house built in the US. With a HERS index of 49, the New American Home is 51% more efficient than the average newly constructed house. And the home’s 19.8 kW solar array gives the house a projected HERS Index of -16. That means it would be 116% more efficient than the average code minimum new house and it will produce more energy than it uses. TNAH, as I told you, is a tight house. During a blower door test, they found that the building envelope had a leakage rate of only 2.35 Air Changes per Hour. A good goal for most of our houses is 3 or fewer air changes per hour ACH(50). Ultra tight Passive Houses have a leakage rate of only 0.6 ACH, which is way tighter than most of our houses will ever be. That means there is minimal air leaking into or out of the house. We want any cooled or heated air produced by our HVAC system to stay in the house and any uncomfortably cold or hot air from outside to stay out of the house. And the tighter house, the less leakage and the smaller and less expensive an HVAC system you can purchase without compromising comfort. With its tight building envelope and energy efficient design, TNAH will result in almost $4000 in annual energy savings. Not only does the home focus on energy savings, but also on air quality and water conservation. Kohler low-flow water fixtures, low maintenance, low water native landscaping, and a high-efficient drip irrigation system were utilized so the house will achieve a 72% reduction in water use. To improve air quality, the HVAC ducts were sealed during construction to prevent construction particles and pollutants from entering the homes duct system and contaminating the conditioned air. Formaldehyde free cabinets and Sherwin Williams Low-VOC paints and finishes and low-VOC interior adhesives and sealants were used. The house also had MERV 13 air filters. MERV stands for Minimum Efficiency Reporting Value. But what you want to remember is the higher the MERV rating, the greater percentage of contaminant particles an air filter can catch. A MERV 13 is pretty much what we should be looking for. Throughout the design and construction process of the New American Home, the relationship between building site, the building envelope, and mechanical/HVAC systems were carefully considered to come up with a high performance strategy that added little, if any, extra cost to the project. Here are some of the approaches used in The New American Home that we can duplicate for our projects, no matter our home’s size or budget: 1. Considering the house site and sun orientation when positioning the house. In the US, having lots of windows on the south side of your house gives you warm sun in the winter and lots of light all year round. You can add generous roof overhangs and/or exterior shades/screens to shade those south side windows in warm or hot climates. West facing windows should be avoided or minimized in almost all climates. 2. To create a tight building envelope we can air seal ducts and exterior openings and shoot for a blower door test air leakage rate of 3 ACH (50) or less. Don’t forget to invest in mechanical ventilation to take stale air out and bring fresh air in. 3. Meet Energy Star minimum insulation and window construction targets, which you can find on the Energy Star website. 4. Purchase the most efficient HVAC system we can afford based on a Manual J calculation or something equivalent. Consider a variable speed system, if it’s in your budget. And put the HVAC system in a conditioned space. 5. To further reduce energy usage, install LED lighting and Energy Star appliances. 6. To save water, look into low flow plumbing fixtures, a drip irrigation system and landscaping primarily comprised of plants that are native to your area so they won’t need excessive watering. Let’s finish this summary up with a couple of quiz questions: QUIZ 1. True or False: Indoor shades and outdoor solar screens/shades are equally efficient in reducing heat from the sun coming into a house? That’s false. Exterior screens are typically 7X more effective at reducing building heat gain as compared to interior shades. So if you live in a hot or warm climate, strongly consider investing in outdoor solar screens/shades and/or sun blocking roof overhangs. To learn more about why roof overhangs are important, take a listen to episodes 173 and 174 2. True or False: To increase air quality, choose low VOC paints and finishes, formaldehyde free cabinets and furniture and MERV 13 air filters. That’s true. VOC stands for volatile organic compounds and they are released from some materials and can make some people sick. MERV stands for Minimum Efficiency Reporting Value. The higher the MERV rating, the greater percentage of contaminant particles an air filter can catch. A MERV 13 is pretty much what we should be looking for. Please remember that the purpose of this podcast is simply to educate and inform. It is not a substitute for professional advice. The information that you hear is based the only on the opinions, research and experiences of my guests and myself. That information might be incomplete and it’s subject to change, so it may not apply to your project. In addition, building codes and requirements vary from region to region, so always consult a professional about specific recommendations for your home. Thanks for stopping by. I hope you learned as much as I did.
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