Standard Practice for Determining Steady State Thermal Transmittance of Fenestration Systems

Importancia y uso:

4.1 This practice details the test specimen sizes and test conditions, namely, the room-side and weather-side air temperatures, and the surface heat transfer coefficients for both sides of the test specimen, when testing fenestration products in accordance with Test Method C1199.

4.2 The thermal transmittance and conductance of a specimen are affected by its size and three-dimensional geometry. Tests should therefore be conducted using the specimen sizes recommended in 5.1. Should the specimen size differ from those given in 5.1, the actual size shall be reported in the test report.

4.3 Many factors can affect the thermal performance of a fenestration system, including deflections of sealed glazing units. Care should be exercised to maintain the original physical condition of the fenestration system and while installing it in the surround panel.

4.4 The thermal transmittance and conductance results obtained do not, and are not intended, to reflect performances expected from field installations since they do not account for solar radiation and air leakage effects. The thermal transmittance and conductance results are taken from specified laboratory conditions and are to be used only for fenestration product comparisons and as input to thermal performance analyses that also include solar and air leakage effects.

Subcomité:

E06.51

Referida por:

E0631-15R24, C1363-24, C1199-22

Volúmen:

04.11

Número ICS:

91.060.50 (Doors and windows), 91.120.10 (Thermal insulation of buildings)

Palabras clave:

doors; fenestration; heat; heat transfer; hot box; skylight; steady state; surround panel; thermal performance; transmittance; U-factor; windows;