800 likes | 1.12k Views
Glass and thermal insulation 2008. Technical Advisory Service. Thermal Insulation. Acoustic Insulation. Solar Control. Safety. Aesthetic and decoration. Glass and thermal insulation. Introduction Convection, conduction and radiancy Single glazing Double glazing
E N D
Glass and thermal insulation 2008 Technical Advisory Service
Thermal Insulation Acoustic Insulation Solar Control Safety Aesthetic and decoration
Glass and thermal insulation • Introduction • Convection, conduction and radiancy • Single glazing • Double glazing • Low e double glazing • Temperature of surface and comfort • AGC Flat Glass Europe range • Condensation • Calculation of the Ug-value of a glazing • Calculation of the Uw-value of a window • Regulation
Introduction Heat high t° low t°
Introduction 20°C Necessary power ? 0°C P = S (m²) x DT (°C) x Ug (W/m² °C)
Glass and thermal insulation • Introduction • Convection, conduction and radiancy • Single glazing • Double glazing • Low e double glazing • Temperature of surface and comfort • AGC range • Condensation • Calculation of the Ug-value of a glazing • Calculation of the Uw-value of a window • Regulation
Conduction, convection and radiancy Conduction Convection Radiancy
Conduction, convection and radiancy Heat loss Ug-value = (W/m².K) Temperature difference Outdoor temperature : Tout Indoor temperature : Tin Radiation Radiation Conduction Convection (and conduction) Convection (and conduction)
Conduction, convection and radiancy Energy UV Light Short infra red Intensity(W/m²) 1.5 1.0 0.5 0 2500 280 380 780 0 Wavelength (nm)
Conduction, convection and radiancy Solar spectrum : UV : 280 tot 380 nm 5% energy Light : 380 tot 780 nm 50% energy Short I.R. : 780 tot 2500 nm 45% energy
Conduction, convection and radiancy Solar radiancy Radiators Close IR Radio waves Visible Long IR
Glass and thermal insulation • Introduction • Convection, conduction and radiancy • Single glazing • Double glazing • Low e double glazing • Temperature of surface and comfort • AGC range • Condensation • Calculation of the Ug-value of a glazing • Calculation of the Uw-value of a window Regulation
Single glazing 4 glass = 1 W/(m K) alu = 160 W/(m K) insulating material 0,065 W/(m K) : thermal conductivity
Single glazing 19 mm Ug = 5,4 W/(m² K) 4 glass = 1 W/(m² K) insulator < 0,065 W/(m² K) Ug = 5,8 W/(m² K)
Single glazing 5,8 5,4
Single glazing 700 mm Ug = 1.1 W/(m² K)
Glass and thermal insulation • Introduction • Convection, conduction and radiancy • Single glazing • Double glazing • High output double glazing • Temperature of surface and comfort • AGC range • Condensation • Calculation of the Ug-value of a glazing • Calculation of the Uw-value of a window • Regulation
Double glazing glass = 1 W/(m² K) air = 0,025 W/(m² K) Ug = 5,8 W/(m² K) Ug = 2,9 W/(m² K)
Double glazing 2,9
Double glazing - composition Thermobel Air Float Float Butyl Spacer Dryer Sealing
Double glazing - composition • 2 glazings • Spacer • Gas • Dryer for absorbing humidity • Primary barrier of sealing (humidity) : • Butyl • Secondary barrier of sealing (sealing) : • Polyurethane • Silicone
Double glazing Ar Kr Ug = 2,9 W/(m² K) Ug 2,6 W/(m² K)
Double glazing Ug = 2,9 W/(m² K) Ug 2,0 W/(m² K)
Glass and thermal insulation • Introduction • Convection, conduction and radiancy • Single glazing • Double glazing • Low edouble glazing • Temperature of surface and comfort • AGC range • Condensation • Calculation of the Ug-value of a glazing • Calculation of the Uw-value of a window • Regulation
Double glazing Outside Inside UV, visible, short IR Long IR > 2500 nm
Double glazing Long IR > 2500 nm en=0.89 en =0.89
Double glazing • Glass is not transparent to long IR • Glass then absorbs the heat which tries to leave the building • In winter, when it is colder outside than inside, the major part ofthis absorptive energy is re-emitted towards outside
Low e double glazing Heat LowE coating Ug = 2,9 W/(m² K) Ug = 1,4 to 2,0 W/(m² K)
Low e double glazing Low emissivity coating : n=0.15 to 0.02 Long IR > 2500 nm en =0.89
Low e double glazing UV, visible, short IR Long IR > 2500 nm en =0.89
Low e double glazing • The low-e coating forces the reemission of the absorbed heat by glass towards the interior • I.e. that it behaves as a mirror which reflects the heat which tries to leave the building • On the other hand, it does not prevent the solar radiation frompenetrating in the building
Low e double glazing • Physically : • Glass is opaque to long IR (ET = 0) • From where the result of a heating of glass and reemission • The low-e coating forces the reeimisson towards outside • = AE = 1 – TR – RE = 1 – RE • The lower is emissivity, the higher is the energy reemission towards the interior
Low e double glazing Clear glazing : emissivity e = 0,89 Coatings : • pyrolithic low-e: e about 0,15 to 0,30 • Vacuum(magnetron): e about 0,02 à 0,1
Low e double glazing e = 0,89 e = 0,15 e = 0,05
Double glazing with Warm Edge spacer The metallic spacer (alu, steel, …) is replaced by a plastic spacer (eventually reinforced).
Double glazing with Warm Edge spacer Advantages: • Improvement of the U-value of the frame (not the glazing) economy of energy • The surface temperature is more uniform better comfort Without Warm Egde With Warm Edge
Low e double glazing In short : • Thickness of glass : insignificant • Gas (argon): small improvement • Low emissivity coatings Big improvement Low e double glazing • Warm-Edge spacer Improvement of the insulation of the frame
Double glazing Ar Ug = 5,8 W/(m² K) Ug = 2,9 W/(m² K) Ug from 1,4 to 2,0 W/(m² K) Ug = 1,1W/(m² K) In short :
Triple glazing Ar Kr Ar Kr Ug from 0,5 to 0,9 W/(m² K)
Thermal losses of a dwelling... Roof : 20% Walls : 25% Ground : 20% Windows account for about 35% !
Glass and thermal insulation • Introduction • Convection, conduction and radiancy • Single glazing • Double glazing • Low e double glazing • Temperature of surface and comfort • AGC range • Condensation • Calculation of the Ug-value of a glazing • Calculation of the Uw-value of a window • Regulation
Temperature of surface and comfort 20° 18,5° 17,3° 12,8° 5,6° 0° Thermobel Triple 4-15 ar-4 -15 ar-4Ug = 0,6 Planibel 4 mm Ug =5,8 Thermobel 4-12-4 mm Ug = 2,9 Thermobel Top N+ 4-15 ar-4 mm Ug = 1,1 Inside Outside
Glass and thermal insulation • Introduction • Convection, conduction and radiancy • Single glazing • Double glazing • Low e double glazing • Temperature of surface and comfort • AGC range • Condensation • Calculation of the Ug-value of a glazing • Calculation of the Uw-value of a window • Regulation
1970 1980 1990 2000 1970 1980 1990 2000 Technology Dial Sputtering Lodelinsart Magnetron sputtering Lodelinsart / Tiel / Teplice Pyrolytic (Spray) Moustier Pyrolytic (CVD) Moustier Gold Thermoplus Single silver Thermobel (Plus, Top, Top N, Energy) Top N+, Top NT, Energy N Thermoplus Comfort K Glass Planibel G
AGC range – Thermobel • Ug = 2,8 W/m²K • LT = 81 % - SF = 77 % • Dimensions max : 3210 mm x 6000 mm • Thicknesses : 4 to 19 mm • Processings : tempering, laminating, silk screening, bending
AGC range – Thermobel Alternatives • Thermobel cross bars • Thermobel luxaclair
AGC range – Thermobel Top N+ • LT = 78 % - SF = 60 % • Top N+ (ar): Ug = 1,3 – 1,1 W/m²K • Dimensions max: 3210 mm x 6000 mm • Standard thicknesses: 4 - 5 - 6 - 8 - 10 - 12 mm • Processings: laminating