Glossary & Terminology

U-Value

(Heat Transfer Co-efficient)

The U-value, also known as the overall heat transfer coefficient, represents the rate of heat transfer through a material or assembly. It measures how well a material or construction component insulates against heat loss or gain. A lower U-value indicates better insulation properties, meaning less heat is transmitted through the material.

SHGC

(Solar Heat Gain Co-efficient)

SHGC stands for Solar Heat Gain Coefficient. It is a measure of how much solar radiation passes through a window or glazed surface into a building. The SHGC represents the fraction of solar radiation that enters a building through a window, with values typically ranging from 0 to 1. A lower SHGC indicates less solar heat gain, which is beneficial for reducing cooling loads in warm climates.

STC

(Sound Transmission Co-efficient)

STC stands for Sound Transmission Class. It is a rating system used to measure how well a building partition, such as walls, floors, or windows, reduces the transmission of airborne sound. The higher the STC rating, the more effective the partition is at blocking sound. STC ratings typically range from 25 to 80, with higher values indicating better sound insulation.

NAFS

(North American Fenestration Standard)

NAFS is a set of guidelines and performance criteria developed by the American Architectural Manufacturers Association (AAMA), the Canadian Standards Association (CSA), and the Window and Door Manufacturers Association (WDMA) to evaluate the structural integrity, air leakage, water penetration resistance, and forced entry resistance of windows, doors, and skylights. NAFS provides a standardized method for testing and rating the performance of fenestration products, ensuring they meet specific quality and safety standards for use in North America.