Fenestration Performance: 4
glass only center to skylight glass only center
ASHRAE Chapter 15 fenestration U-factors (W/m²·K) for windows, skylights, curtain walls, and doors by glazing configuration and frame type. Covers single through quadruple glazing with air, argon, and krypton fill, low-e coatings at various emissivities, and all major frame materials. Source: ASHRAE Handbook Fundamentals 2021 Tables 4 and 6.
| glazing id | frame type | gap fill | gap mm (mm) | glazing category | glazing type | num panes (dimensionless) | u factor Wm2K (W/(m2·K)) |
|---|---|---|---|---|---|---|---|
| 4 | glass only center | air | 6 | Double Glazing | 6 mm airspace | 2 | 3.12 |
| 4 | glass only edge | air | 6 | Double Glazing | 6 mm airspace | 2 | 3.63 |
| 4 | operable alum no break | air | 6 | Double Glazing | 6 mm airspace | 2 | 4.62 |
| 4 | operable alum thermal break | air | 6 | Double Glazing | 6 mm airspace | 2 | 3.61 |
| 4 | operable insul fiberglass vinyl | air | 6 | Double Glazing | 6 mm airspace | 2 | 2.84 |
| 4 | operable reinf vinyl alum clad | air | 6 | Double Glazing | 6 mm airspace | 2 | 3.24 |
| 4 | operable wood vinyl | air | 6 | Double Glazing | 6 mm airspace | 2 | 3.14 |
| 4 | skylight alum no break | air | 6 | Double Glazing | 6 mm airspace | 2 | 6.23 |
| 4 | skylight alum thermal break | air | 6 | Double Glazing | 6 mm airspace | 2 | 5.46 |
| 4 | skylight glass only center | air | 6 | Double Glazing | 6 mm airspace | 2 | 3.29 |
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