Energy Star Rated Homes | sustainableliving

Energy Star Rated Homes:

Energy efficiency in an eco-home is of prime area importance both for sustainability as well as for keeping costs low to increase quality of life. Creating a quality of life that allows the user to enjoy time with family and pursue interests that contribute to their well being. Having high energy bills as well as a high mortgage create stress and anxiety that creates a lower quality of life for the inhabitants. Energy efficiency in an eco home should be of prime importance to the designer and a moral imperative as it can help increase the quality of life and longevity of its inhabitants.

Depending on the region eco-houses may not have to the strictest building permit standards yet they should create a quality of life as well as create a habitable space that conforms to local geographical requirements for construction whether its an earthquake area or hurricane zone. Energy efficiency is more important because it creates a less negative impact on the environment and keeps a less negative impact on the environment as well as helps to keep costs low for the inhabitants. While a "LEED Platinum" home for example can receive tax credits for meeting government's standards as noted by the U.S. Green Building Council it may not necessarily be the most energy efficient option for the inhabitants. Size of the home is of critical importance as it needs to stay small for the house to be energy efficient as well as not creating an negative impact. The average size of the home has increased by over 40 percent in the last 60 years. The average size of the home has increased from 1950 at about 1400 square feet to 2400 square feet in 2015 (“realtytrac.com", nod., Size Matters Measuring Homes Per Decade, Para 1-2). While the size of the home has increased the actual amount of space being utilized in each home has not as most people use less than 50% of the home at any one time. Activities in the home are becoming more centralized such as computer usage which needs less space. For example, many people now use tablets to draw from my computer replacing the old drawing desk or drawing board which takes up less than 75 of the space a typical drawing board would need. This is an example of how our new activities and new lifestyle actually allow us to actually need less space. Heating and cooling a part of the home that is not being utilized is wasteful. The standard we're developing for these eco- house prototypes are 600 to 800 one and provide options for accessibility and an 800 to 1000 square feet for a family of four with accessibility options. Accessibility in every home provide options for a single or elderly seniors that may want an energy efficient eco-home lifestyle that provides aging in place.

An energy star rated home provides comprehensive air sealing, properly installed insulation, and high-performance windows which work together to enhance comfort, improve durability, reduce maintenance costs, and lower monthly utility bills. The Heating and Cooling System is engineered and installed to deliver more comfort, better moisture control, improved indoor air quality, and quieter operation. Each home should have a complete Water Management System which is a comprehensive package of best building practices and materials protects roofs, walls and foundations from water damage, provides added protection, and reduces the risk of indoor air quality problems. The home should also include Energy-Efficient Lighting and Appliances. ENERGY STAR certified lighting, appliances, and fans are commonly installed throughout ENERGY STAR certified homes, helping to reduce monthly utility bills, while providing high-quality performance.

The United States Environmental Protection Agency (EPA) released a new set of guidelines for ENERGY STAR qualified homes implemented in 2006 and a major new requirement is the Thermal Bypass Checklist. The Thermal Bypass Checklist is a comprehensive list of building details where thermal bypass, or the movement of heat around or through insulation, frequently occurs due to missing air barriers or gaps between the air barrier and insulation. The Thermal Bypass Checklist must be completed by a certified home energy rater in order for a home to be qualified as ENERGY STAR, however, up to six items may be verified by the builder to minimize required field trips by the rater.

Generally, the Thermal Bypass Inspection Checklist requires a sealed air-barrier on all six sides of insulation (top, bottom, back, front, left, and right). Blown cellulose insulation or spray foam insulation are good options that will fill holes and cracks and create an airtight wall assembly for the home.

Figure 1: The air barrier should be contiguous and continuous over the entire building

envelope. Insulation should be perfectly aligned with the air barrier.

Air loss through the slab is another issue and there are two basic ways to insulate a slab. First, rigid insulation can be installed directly against the exterior of the slab. A second option is a “floating slab,” which can be constructed using interior insulation. In both cases, insulation should be continuously aligned with the air barrier (see Figure 2).

Figure 2: Options for slab insulation

http://www.energystar.gov http://www.energystar.gov

Exterior rigid insulation wall sheathing can be used to provide a complete thermal break at all wall framing (see Figure 3). The only uninsulated wall areas are the window and door openings. Floors and ceilings in garages need to be insulated as well to meet energy star rating requirements.

Penetrations in framing made by plumbers, electricians, or HVAC contractors can allow excessive air leakage. Sealing duct and plumbing penetrations involves fully sealing the holes leading to unconditioned spaces with caulk or foam and providing flashing where needed for very large air spaces (see Figure 4). Openings to unconditioned spaces shall be sealed with solid blocking as required and any remaining gaps shall be sealed with caulk or foam.

Figure 4: (Left) Advanced interior/exterior wall framing techniques http://www.energystar.gov

Figure 4A – (Middle) Penetrations leaving large holes http://www.energystar.gov

Figure 4C – (Right) Caulking around piping penetration http://www.energystar.gov