Crystalite Launches .30/.30 Skylight
Everett, Wash.-based Crystalite Inc. reports it is the first manufacturer to offer a skylight listed with the National Fenestration Rating Council meeting the .30/.30 tax credit criteria. The company's ES Skylight frame is hybrid, combining its standard aluminum frame skylight with a drop-in PVC enhancement panel frame that extends down into the daylight opening.
Cutaway of the new Crystalite ES Skylight
The process of getting the skylight certified began just after passage of the stimulus package. "We happened to have an advanced frame design that we felt could meet the requirements," reports Crystalite's John Westerfield. "This frame was intended for improved thermal performance for a particular plastic glazing application, however due to NFRC's lack of skylight conscious procedures, we could not get NFRC certified values."
Using the frame with Cardinal LoE 366 glass, the skylight offered estimated values of .26/.26, he states. "However, it took nearly 6 months for a (technical interpretation) to be approved by NFRC's technical committee which would allow the frame to be certified."
The skylight's drop-in enhancement panel creates a large insulated air space with the aluminum frame to enhance the unit's thermal performance, but it created a problem as the U-factor could not be calculated using NFRC's standard procedures. Quality Testing's Randy Van Voorst could "hand calculate" the values, however, which led to the technical interpretation, Westerfield explains.
In addition to meeting the tax credit requirements, Westerfield notes that due to Crystalite's geographical location, high snow load criteria was also a concern. "The ES Skylight is NAMI certified in accordance with the NAFS standard (AAMA/WDMA/CSA 101/I.S.2/A440) for positive loads of up to 330 psf," he reports. "These higher, cold climate areas would benefit the most from utilizing the highly insulated ES Skylight."
Another benefit of the two-part hybrid frame is that the skylight can accommodate any curb thickness. "Larger curbs are not uncommon for buildings with flat roofs and for skylights in high snow load areas," Westerfield states.