Green Terminology

ACH: Air Changes per Hour. The lower the number is the more efficient. This is testing to determine how much air leaks through the walls and ceilings.

• ASHRAE: American Society of Heating, Refrigerating and Air-Conditioning Engineers. The primary organization used in the US for the design standards in our HVAC systems.

• Energy Star™: Department of Energy program mandating a minimum 15% more energy efficient home than one built in 2004.

• HVAC: Heating, Ventilation and Air Conditioning.

• IAQ: Indoor Air Quality

• IRC: International Residential Code. The IRC is the Building Code for the State of Texas.

• Jump Duct: A flexible, short, u-shaped duct that connects a room to a common space as a pressure balancing mechanism.

• LEED: Leadership in Energy and Environmental Design

• Low E2: Low emissive. Glass is coated with a metallic oxide layer that improves thermal performance.

• Manual J: The ASHRAE method for calculating residential home cooling loads and the sizing of the system.

• MERV: Minimum Efficiency Reporting Value: The ASHRAE standard for filter efficiency. The higher the rating the better is the energy efficiency.

• Pressure Balancing: To equalize air pressures between rooms in a house by adjusting air flow in supply and return ducts.

• R-410a: Environmentally friendly refrigerant used in our HVAC systems.

• R-Value: Resistance – Value. The resistance a material has to heat flow. The higher the R value the greater the resistance.

• SEER: Seasonal Energy Efficiency Rating. It measures the efficiency of the air conditioner once it is up and running. Higher the number is better efficiency rating.