Service

Building Performance Testing

• Duct Blasting
  The development of the Duct Blaster has revolutionized performance testing of forced air distribution systems for builders, HVAC contractors, and utility DSM programs. The Duct Blaster is a calibrated air flow measurement system designed to test and document the air tightness of forced air duct systems in both houses and light commercial buildings. The Duct Blaster fan is connected directly to the duct system in a house, typically at a central return, or at the air handler cabinet. With the remaining registers and grilles temporarily taped off, duct air tightness is measured by either pressurizing or depressurizing the duct system and precisely measuring the fan flow and duct pressure.
  
  Duct air tightness measurements are used to diagnose and demonstrate leakage problems, estimate efficiency losses from duct leakage, and certify compliance with duct leakage standards such as California’s Title 24 Building Energy Efficiency Standards.
  
  
  
• Blower Door Testing
  
  Professional energy auditors use blower door tests to help determine a home’s air tightness.
  
  These are some reasons for establishing the proper building tightness:
  
  
  • Reducing energy consumption due to air leakage
  • Avoiding moisture condensation problems
  • Avoiding uncomfortable drafts caused by cold air leaking in from the outdoors
  • Making sure that the home’s air quality is not too contaminated by indoor air pollution.



How They Work

A blower door is a powerful fan that mounts into the frame of an exterior door. The fan pulls air out of the house, lowering the air pressure inside. The higher outside air pressure then flows in through all unsealed cracks and openings. The auditors may use a smoke pencil to detect air leaks. These tests determine the air infiltration rate of a building. Blower doors consist of a frame and flexible panel that you can place in a doorway, a variable-speed fan, a pressure gauge to measure the pressure differences inside and outside the home, and an airflow manometer and hoses for measuring airflow.

Combustion/ Back Draft Testing

Initiate a blower door test to confirm that the combination of ventilation systems (i.e. range hoods, bathroom fans) and other exhaust systems (central vacuum cleaners, clothes dryers) don’t cause the home depressurization levels to fall into unsafe back draft levels. The increase in carbon monoxide sensors and the move to direct vent, closed combustion heating systems will help to minimize the risk of carbon monoxide poisoning.

Carbon Monoxide Testing

You can’t see or smell carbon monoxide, but at high levels it can kill a person in minutes. Carbon monoxide (CO) is produced whenever any fuel such as gas, oil, kerosene, wood, or charcoal is burned. If appliances that burn fuel are maintained and used properly, the amount of CO produced is usually not hazardous. However, if appliances are not working properly or are used incorrectly, dangerous levels of CO can result. Hundreds of people die accidentally every year from CO poisoning caused by malfunctioning or improperly used fuel-burning appliances. Even more die from CO produced by idling cars. Fetuses, infants, elderly people, and people with anemia or with a history of heart or respiratory disease can be especially susceptible.



Duct Restoration, Sealing, and Duct Insulating

Air distribution system ducts are designed to supply conditioned air from space heating and cooling equipment to the living spaces and return an equal volume of air from the living spaces back to the heating and cooling equipment to be conditioned. However, residential ducts typically leak 15 percent to 20 percent of the air they convey.

Ducts are usually located in unconditioned spaces such as attics, crawlspaces, garages, or unfinished basements. The conditioned air that leaks out of the supply ducts is lost in the spaces where the ducts are located. Typically, heating and cooling equipment is designed to condition return air that is at or near room temperature. Leaky return ducts can draw air out of unconditioned spaces that is hotter or colder than the return air, thus increasing loads on heating and cooling systems. This problem is most pronounced in attics where, during the summer months, air temperatures can be 150°F or higher. Even when furnaces or air conditioners are not operating, leaky ducts waste energy by contributing to the overall air leakage of a house. In new, tightly constructed houses, ducts can account for 20 percent to 25 percent of the total air leakage. Leaky ducts located in unconditioned spaces can introduce airborne pollutants, moisture, and unpleasant odors into homes, thus reducing indoor air quality.

Duct leakage is the result of improper installation and poor materials. Duct tape, which is commonly used, does not adequately seal joints between ducts and has a short life. More stable and permanent materials are needed such as foil tape, fiberglass tape and mastic, or new advanced duct tape. Locating the ducts within the conditioned space can also improve system efficiency. Even when ducts are located within conditioned spaces, sealing is still required to assure proper air distribution.

Air Sealing the Building’s Envelope

Many air leaks and drafts are easy to find because they are easy to feel — like those around windows and doors. But holes hidden in attics, basements, and crawlspaces are usually bigger problems. Home sealing will have a great impact on improving your comfort and reducing utility bills.

Homeowners are often concerned about sealing their house too tightly; however, this is very unlikely in older homes. Tightly sealed homes with proper mechanical ventilation have reduced indoor air pollution.

A vapor barrier or vapor diffusion retarder (VDR) is a material that reduces the rate at which water vapor can move through a material. The older term "vapor barrier" is still used even though it may inaccurately imply that the material stops all of the moisture transfer. Since everything allows some water vapor to diffuse through it to some degree, the term "vapor diffusion retarder" is more accurate.

The ability of a material to retard the diffusion of water vapor is measured by units known as "perms" or permeability. A perm at 73.4°F (23°C) is a measure of the number of grains of water vapor passing through a square foot of material per hour at a differential vapor pressure equal to one inch of mercury (1" W.C.) Any material with a perm rating of less than 1.0 is considered a vapor retarder.

Vapor diffusion retarders can help control moisture in these areas:

• Basements
• Ceilings
• Crawl spaces
• Floors
• Slab-on-grade foundations
• Walls
• Effective moisture control in these areas and throughout a home includes air sealing gaps in the structure, not just the use of a vapor diffusion retarder

Rodent Barrier Installation and Repair

Protective sheeting covering the bottom of homes, shielding insulation, ducts and the underside of the home from environmental degradation including rodent damage. Rodent Barriers can also help with heat loss from floors.

Available Services

Blower Door Testing
Duct Blaster Testing
Heat Pump Commissioning
Duct Sealing, Restoration and Insulation
Air Sealing
Vapor Barrier Repair and Installation
Rodent Barrier Repair and Installation
Dryer Vent Repair
Air intake and Exhaust Testing and Repair
Mechanical Ventilation