Building Control
Fire Safety
Your friend in indoor comfort & safety systems
Home Company Services Case Studies References Agencies Daikin-Vrv Handbook Fires / Hotels Links Save Energy Contact Us
Eco Homes

Solar Water Heeating

Solar Electric Systems
Wind Turbines
Passive Solar Heating
Passive Solar Cooling
Water Conservation
Building Material
Ground Source Heat Pumps
Eco Cases
Save Energy
Solar Water Heating
Solar Electric Systems
Wind Turbines
Passive Solar Heating
Passive Solar Cooling
Building Material
Water Conservation
Ground Source Heat-Pumps
Green Hotels

Glass &Windows Selection

Standalone Systems
Grid Connected Systems
Hybrid Systems
Back-up Systems
Solar Cells
Solar Arrays
Change Controller
Direct Systems
Indirect Systems
Draindown Systems
Pool Heating Systems
Hybrid Systems
Grid Systems
Water Pumping
Using Wind Energy
Enviromental Aspects
Buyer's Guide
Solar Collectors
Flat Plate Collectors
Evacuated Tube Collectors
Concentrating Collectors
Transpired Collectors
Solar Control Systems
Big Hotel Fires
Hotel Fire Cases
Fire Hazard Classification
Hotel Sprinkler Systems

Hotel Fire News

Ask The HvacMan
Air Handling Units
Cooling Towers
Heat Recovery

Steam Generation

Glass Emittance

Glass Emittance

When heat or light energy is absorbed by glass, it is either convected away by moving air or reradiated by the glass surface. This ability of a material to radiate energy is called its emissivity. Windows, along with all other objects, typically emit, or radiate, heat in the form of long-wave far-infrared energy. This emission of radiant heat is one of the important heat transfer pathways for a window. Thus, reducing the window's emission of heat can greatly improve its insulating properties.

Standard clear glass has an emittance of 0.84 over the long wavelength portion of the spectrum, meaning that it emits 84 percent of the energy possible for an object at its temperature. It also means that for long-wave radiation striking the surface of the glass, 84 percent is absorbed and only 16 percent is reflected. By comparison, low-E glass coatings have an emittance as low as 0.04. This glazing would emit only 4 percent of the energy possible at its temperature, and thus reflect 96 percent of the incident long-wave infrared radiation.

Glass & Windows 101
Glass Transmittance
Glass Reflectance
Glass Absorptance
Back to Glass&Windows


Web www.iklim.com
  Discuss on the Message Board
Book & Magazine
Interstate Bank Fire
Beverly Hills Club Fire
MGM Fire
Firehause Magazine
Special Fires
Hotel Fires
Ship Fires
Industrial Fires
Warehouse Fires

Restaurant/Nightclub Discotheque-Fires

High Rise Fires
Fires ABC
Big Building Fires
Book About Fires
Fire Stats
Fire Board

Books About Fires

Energy Save
Hotels & Legionella
Green Hotels
Hotel Design Books
Control Software