Skylight Design, Structural Glass, Commercial Skylight, Overhead Glazing

Skylights and sloped glazing recent code changes

The 2012 IBC has different requirements for factory-built unit skylights than for other types of glazed assemblies in roofs such as skylights and sloped glazing. Factory-built unit skylights that contain only one panel of glazing material are required to be tested and labeled for performance grade in accordance with AAMA/WDMA/CSA 101/I.S.2/A440-11 in the 2012 IBC. Section 2405.5 of the 2012 IBC establishes the required performance-grade rating based on the provisions of that code for wind, snow and dead loads.

As for vertical glass, glass in sloped glazing is to be designed in accordance with ASTM E 1300-07e01. The requirements for screening under skylights and sloped glazing, as set forth in Section 2405.3 of the 2012 IBC, are consistent with previous editions of the International Codes. This includes requiring the screening to be securely fastened to the framing and to be able to support twice the dead weight of the glass. Requirements for curbs on skylights and sloped glazing, when applicable, is also consistent with those in the previous editions of the International Codes, and are set forth in Section 2405.4 of the 2012 IBC.

Sunroom additions recent code changes

The 2012 IECC permits glazing in thermally isolated sunrooms to have a maximum U-factor of 0.45 in climate zones 4 to 8. By definition, a thermally isolated sunroom must be separated from the remainder of the building by either existing exterior wall construction or construction that meets the energy efficiency requirements of the 2012 IECC for exterior walls. The sunroom must also be equipped with a separate heating or cooling system or thermostatically controlled as a separate zone, if conditioned. Previous editions of the IECC placed size restrictions on thermally isolated sunrooms but these restrictions do not occur in the 2012 IECC.

Sunrooms must be thermally isolated from the remainder of the home to take advantage of the higher permitted U-factor for fenestration. Under the 2012 IECC, sunrooms can be built as part of new construction, but they must still be thermally isolated from the remainder of the home, as discussed above, to use the U-factor of 0.50 rather than 0.35 in climate zones 5 to 8, or 0.40 in climate zone 4.