infiltration | AiDomes

EPA Energy Star

Exhaust Ventilation Systems

To read about the Ai dome and Heat Recovery Ventilators, click on HRV.  To read the most common asked energy questions with answers, click on Energy FAQ.  To read about the Ai dome and geothermal pipes, click on GeoThermal

The following came from the EPA’s Energy Star web site:

http://energystar.gov/ia/new_homes/features/ExhaustVentilation1-17-01.pdf 

The air within homes can become stale from moisture, odors, and pollutants that penetrate the home or are generated internally by human activity and out gassing from building materials and furnishings.  A constant supply of fresh, outdoor air can provide greater assurance of good indoor air quality and improved comfort. 

In most homes, ventilation is provided accidentally when air leaks through the building envelope.  Accidental ventilation is unreliable because it is dependent on a pressure difference between indoor and outdoor spaces caused by temperature or wind variations.  Too much fresh air often enters a house during cold weather, causing uncomfortable drafts and high heating bills.  Not enough fresh air may enter during mild weather which can lead to poor indoor air quality. 

Air leakage through the building envelope accounts for between 25 percent and 40 percent of the energy used for heating and cooling in a typical residence.  Many new homes are being air sealed to reduce this energy use.  Where tighter construction reduces air leakage and accidental ventilation, active ventilation systems may be needed to provide fresh air. 

Figure 1 shows how exhaust ventilation works in a small home.  Indoor air is continuously exhausted from a central fan (shown) or remote fans usually located in bathrooms.  Fresh outdoor air can be drawn into the house through remaining leaks in the building envelope.  Homes built with extremely tight envelopes may require the installation of room wall ventilation openings or specially designed windows that allow outdoor air to enter. 

These opening are sized and located to allow the proper amount of fresh air to enter homes without causing uncomfortable drafts and to prevent indoor pressurization.  Kitchens should have separate, manually operated, exhaust fans. 

The advantages of exhaust ventilation are control and consistency.  Moisture, odors and pollutants are removed continuously, regardless of weather conditions.  High indoor air quality is maintained due to the constant infiltration of outdoor air. 

Exhaust ventilation systems are most suitable for moderate climates.  Care must be taken during design and installation to prevent these systems from “back drafting” dangerous combustion gases from fireplaces and gas appliances into homes. 

Resources used for this article:

  1. The Consumer Guide to Home Energy Savings (Wilson and Morrill), Available from the American Council for an Energy Efficient Economy at 510-549-9914
  2. Moisture Control in Homes fact sheet available from the Energy Efficiency and Renewable Energy Clearinghouse (EREC), POBox 3048, Merrifield, VA 22116, (1-800-363-3732)

To read about energy efficiency and the American Ingenuity Dome, view Efficient Ai Dome.

The following information came from:

The United States Environmental Protection Agency’s Energy Star Program’s web site is Energy Star.

Air will leak through a building envelope that is not well sealed. This leakage of air decreases the comfort of a residence by allowing moisture, cold drafts and unwanted noise to enter and may lower indoor air quality by allowing in dust and airborne pollutants. In addition, air leakage accounts for between 25 percent and 40 percent of the energy used for heating and cooling a typical residence.

The amount of air leakage in a house depends on two factors. The first is the number and size of air leakage paths through the building envelope. As shown in Figure 1, these paths include joints between building materials, gaps around doors and windows, and penetrations for piping, wiring, and ducts. The second factor is the difference in air pressure between the inside and outside.

Pressure differences are caused by wind, indoor and outdoor temperature differences (stack effect), chimney and flue exhaust fans, equipment with exhaust fans (dryers, central vacuums) and ventilation fans (bath, kitchen. To prevent air leakage, it is important to seal the building envelope during construction prior to installation of the drywall. Once covered, many air leakage paths cannot be accessed and properly sealed. There are many products available for air sealing including caulks, foams, weather stripping, gaskets and door sweeps.

Air sealing the building envelope is one of the most critical features of an energy efficient home. Look for the results of a “blower door” test (typically included with a Home Energy Rating) to ensure that your Energy Star labeled home had all air leakage paths identified and sealed using appropriate materials.

Once a house is tightly sealed, you will want to make sure there is adequate fresh air for ventilation. It is better to use controlled or active ventilation than to rely on air leakage. In many Energy Star labeled homes, an active ventilation system is installed along with air sealing to ensure that fresh air is provided.

Benefits: air sealing the building envelope can provide many benefits including:

  1. Improved Comfort: A tighter building envelope reduces the amount of unconditioned air, drafts, noise, and moisture that enter your home. Proper air sealing will also minimize temperature differences between rooms. As a result, tight envelopes can maintain a more consistent level of comfort throughout a house.
  2. Improved indoor air quality: A tighter building envelope reduces the infiltration of outdoor air pollutants, dust and radon as well as eliminating paths for insect infestation. Properly sealing the building envelope will also reduce moisture infiltration from outdoor air in humid climates.
  3. Increased quality: Building codes establish the legal minimum construction standards. Energy Star labeled homes, constructed to exceed these codes with air sealing, can offer a better quality product.
  4. Lower Utility Bills: Air leakage accounts for 25 percent to 40 percent of the energy used for heating and cooling and also reduces the effectiveness of other energy-efficiency measures such as increased insulation and high-performance windows. Thus. Air sealing results in lower utility bills.
  5. Fewer condensation problems: Condensation can lead to mold and mildew problems. In hot, humid climates, moisture can enter into wall cavities through exterior cracks and result in costly damage to framing and insulation. In cold climates, gaps in the interior walls allow moisture from warm indoor air to enter wall cavities and attics. This moisture can condense on cold surfaces and lead to structural damage. By significantly reducing air leakage, Energy Star labeled homes can reduce or eliminate these problems.
  6. Reduced obsolescence: Based on recent trends for improved efficiency and higher indoor air quality, tighter building envelopes are expected to become standard practice for the building industry. Since it is both difficult and costly to make the building envelope tighter after a house is constructed, it is best to seal all joints, holes and seams during construction. Energy Star labeled homes constructed to exceed current building codes are therefore, expected to be less vulnerable to obsolescence.
  7. Improved resale position: Air sealing a home can provide the many impressive benefits discussed above and lead to a more comfortable, quieter and better quality home with lower utility bills, fewer condensation problems and reduced obsolescence. These benefits can translate into higher resale value.

Resources used:

    1. The Consumer Guide to Home Energy Savings (Wilson and Morrill), 5th edition, 1996, available from the American Council for an Energy Efficient Economy at 510-549-9914
    2. Homemade Money (Heede and the staff of RMI), 1995, available from the Rocky Mountain Institute at 970-927-3851
    3. Caulking and Weatherstripping fact sheet available from the Energy Efficiency and Renewable Energy Clearinghouse (EREC), POBox 3048, Merrifield, VA 22116, (1-800-363-3732)

The following information covers the U.S. EPA’s Energy Star Program
with a South Carolina Ai dome earning the EPA’s Energy Star.

Please click on arrows to view the photos.

Above is photo gallery of Kolb’s 40′ dome home linked to 27′ two car garage dome
which earned EPA’s Energy Star

The Energy Star label can only be placed on completed houses. The label cannot go on a Building Kit. Some of American Ingenuity’s clients have had their completed dome homes rated and received the Energy Star label. To find out how your dome home can receive an Energy Star Label, call the EPA Energy Star hot line 1-888-782-7937 and ask for a company in your area that can rate your home.

Klaus Kolb’s South Carolina Ai concrete dome house earned EPA’s Energy Star.  Home Energy Partners certified his home used 61% less energy than in comparably-size housing.   He installed a geothermal cooling & heating system. To view pictures & info about his geothermal system, click on System.  Klaus’s total monthly average energy bill was $49. This includes the electricity and propane costs for his entire 1,600 sq.ft. – 40 ft. dome.

Jim Collar’s Utah Ai concrete dome buildings operate off the grid by using photovoltaic’s, masonry heater fireplace and passive solar water tubes. To learn more, click on  Off The Grid.

To view a  fantastic YouTube Video of American Ingenuity 48′ dome with 34′ garage in Albuquerque, New Mexico, click on Gorgeous Dome.  To view Ai’s Energy FAQ’s, click on Efficient Ai Dome.

What does the Energy Star label signify?

Products bearing the ENERGY STAR labels are more energy efficient than standard products, thereby saving energy and money. In general, ENERGY STAR qualified products including: appliances, HVAC equipment, office equipment, residential lighting, and even homes, reduce energy costs by at least 30%.

What is Energy Star?

ENERGY STAR is a government program that offers businesses and consumers energy-efficient solutions, making it easy to save money while protecting the environment for future generations.

Energy efficient choices can save families about a third on their energy bill with similar savings of greenhouse gas emissions, without sacrificing features, style or comfort. ENERGY STAR helps you make the energy efficient choice.

If looking for new household products, look for ones that have earned the ENERGY STAR. They meet strict energy efficiency guidelines set by the EPA and US Department of Energy.

EPA’s ENERGY STAR partnership for businesses offers a proven energy management strategy that helps in measuring current energy performance, setting goals, tracking savings, and rewarding improvements. EPA provides an innovative energy performance rating system which businesses have already used for more than 26,000 buildings across the country. EPA also recognizes top performing buildings with the Energy Star.

The U.S. Environmental Protection Agency’s ENERGY STAR® Program promotes the use of high-efficiency technologies and equipment. ENERGY STAR labeled homes use at least 30% less energy than homes built to meet the national Model Energy Code while maintaining or improving indoor air quality.

Many ENERGY STAR qualified new homes feature tighter construction than that of homes built to the Model Energy Code. Tighter house construction can improve the energy efficiency, air quality, and comfort of your home by eliminating unwanted drafts.

Environmental Protection – the following info came from their site.

Did you know that your home can be a greater source of pollution than your car? In fact, 16 percent of U.S. greenhouse gas emissions are generated from the energy used in houses nationwide.

Energy used in our homes often comes from the burning of fossil fuels at power plants, which contributes to smog, acid rain, and global warming. Simply put, the less energy we use in our homes, the less air pollution we generate.

Tighter home construction can offer you:

  • Improved comfort – reduces drafts, noise, and moisture.
  • Improved indoor air quality – keeps dust, pollen, car exhaust, and insects out of the home.
  • Lower costs – reduces escape of conditioned air.

Unfortunately, there are hundreds of penetrations through a typical home’s exterior (The Ai dome’s tight envelope does not have hundreds of penetrations.  The Ai dome was involved in a US Department of Energy Study on energy efficient housing. The blower door test showed the Aidome to be 56% tighter than the conventional test structure and 29% tighter than the Dow house.) These gaps and holes are often incurred during framing, and from penetrations for wiring, plumbing, and ducts. Air sealing the house’s envelope combined with proper ventilation, can reduce your energy bills and eliminate unwanted drafts and pollutants.

Reduced air infiltration combined with proper ventilation can not only reduces your energy bills but it can also improve the quality of your indoor air. Outdoor air that leaks indoor makes it difficult to maintain comfort and energy efficiency. In addition, air leakage accounts for 25-40% of the energy used for heating and cooling in a typical home.

Today, off-the-shelf technologies such as house wraps, sealants, foams, and tapes reduce air infiltration. In energy-efficient homes, builders use these tools to seal the myriad of cracks and gaps in framing along with hundreds of holes for plumbing, mechanical equipment, and electrical wiring.

These fact sheets are designed to help consumers learn more about the energy efficient improvements to their ENERGY STAR labeled homes. These fact sheets cover:

  1. Air Sealing
  2. Value-Engineered Framing
  3. Balanced Ventilation Systems
  4. Exhaust Ventilation Systems
  5. Supply Ventilation Systems

The following information came from The EPA’s web site http://energystar.gov/index.cfm?c=new_homes.nh_benefits

Benefits of Energy Star Qualified New Homes

Peace of Mind
Home buying is complex enough without having to know all the details of energy-efficient construction. Instead, look for the

government-backed ENERGY STAR label to easily identify homes that are truly energy efficient. Find the house of your dreams and enjoy peace of mind knowing that it also meets strict energy efficiency guidelines.

Lower Ownership Cost
Compared with standard homes, ENERGY STAR qualified homes use substantially less energy for heating, cooling, and water heating-delivering $200 to $400 in annual savings. Over the average 7 to 8 years you may live in your home, this adds up to thousands of dollars saved on utility bills. Additional savings on maintenance can also be substantial.

Better Performance
Properly installed energy-efficient improvements deliver better protection against cold, heat, drafts, moisture, pollution, and noise. An energy-efficient home helps ensure consistent temperatures between and across rooms, improved indoor air quality, and greater durability.

Environmental Protection
Did you know that your home can be a greater source of pollution than your car? In fact, 16 percent of U.S. greenhouse gas emissions are generated from the energy used in houses nationwide.

Energy used in our homes often comes from the burning of fossil fuels at power plants, which contributes to smog, acid rain, and global warming. Simply put, the less energy we use in our homes, the less air pollution we generate.