National Fenestration Rating Council Incorporated NFRC 100-2014[E0A0] Procedure for Determining Fenestration Product U-factors © 2013 National Fenestration Rating Council 6305 Ivy Lane, Suite 140 Greenbelt, MD 20770 Voice: (301) 589-1776 Fax: (301) 589-3884 Email: Website:
Ade = Edge-of-divider area Uc = Center-of-glazing U-factor Ac = Center-of-glazing area Figures None Swinging Doors This section presents additional details specific to side-hinged exterior door systems. This section presents and references methods for determining specific side-hinged exterior door system heat transfer properties or quantities used in the determination of these properties. At this time, the scope of these properties is limited to total door system U-factor. Variations from Standard Product Lines A given series of entrance door systems is defined by skin material, core material, and edge-of-door construction that differ only in: Size; Panel and cut out configurations; The replacement of core and/or panel area with glazing system; Center-of-lite characteristics and edge-of-lite characteristics, such as glazing types, gap widths, glazing lite areas, use of dividers, use of spacers, glazing coatings, gas fills; Opening/non-opening configurations, e.g. X, O, XX, XO, OXXO etc; In-swing or out-swing operation; Door slab changes where one component of the same physical shape with a thermal conductivity that does not differ by more than a factor of 10; Frame components, e.g. headers, jambs and threshold; and Variations in frame and/or door interior/exterior finish, paint, varnish, or stain do not constitute different product lines provided that each of these variations does not change the surface emittance by more than 0.10. Variations from Standard Individual Products Products with multiple sill options, where the sill design changes to accommodate different installation requirements, made of the same materials type shall be different individual products within the same product line.
Full glazing glazing ≥ 0.710 m2 (1101 in2) 533 mm x 1600 mm (21 in x 63 in) 5 vertical 13 horizontal 1Glazing dimensions indicate daylight opening size Table 5-2 – Glazing and Divider Patterns for Sidelites Individual Product For Sidelites with Simulate or Test as1 Optional Caming Pattern 1/4 glazing glazing <0.042 m2 (65 in2) 178 mm x 178 mm (7 in x 7 in) 1 vertical 1 horizontal 1/2 glazing 0.042 m2 ≥ glazing < 0.181 m2 (65 in2 to 281 in2) 178 mm x 889 mm (7 in x 35 in) 1 vertical 8 horizontal 3/4 glazing 0.181 m2 ≥ glazing < 0.252 m2 (281 in2 to 391 in2) 178 mm x 1194 mm (7 in x 47 in) 1 vertical 10 horizontal Full glazing glazing ≥ 0.252 m2 (391 in2) 178 mm x 1600 mm (7 in x 63 in) 1 vertical 13 horizontal 1Glazing dimensions indicate daylight opening size Figures Figure 5-1a – Exterior Door System – Vertical Elevation in Steel Frame The projected door area is the rough opening area less installation clearances. Sidelite area schematic may be identical or similar without perimeter weatherstrip and bottom sweep. Figure 5-1b – Exterior Steel/Composite Door System – Vertical Elevation in Wood Frame The projected door area is the opening area less installation clearances. Sidelite area schematic may be identical or similar without perimeter weatherstrip and bottom sweep. Figure 5-2 – Exterior Wood Door System – Vertical Elevation The projected door area is the rough opening area less installation clearances. Sidelite area schematic may be identical or similar without perimeter weatherstrip and bottom sweep.
Figure 5-3 – Typical 6-Panel Layout Figure 5-4 – Common Frame – Single Unit Type Pressed-Steel Frame Figure 5-5 – Cross Section Pressed Frame Specification Single-unit type pressed frames shall consist of a head, a sill and two jamb pieces, hinge reinforcements, a strike plate reinforcement, and base and wall anchors The wall anchors provided shall be adjustable or fixed masonry anchors, bolts with expansion shells, channel clips, “Z” clips, wood stud anchors, or steel anchors. The head and jamb pieces shall be constructed, as shown in Figure 5-4. Figure 5-6 – Wood Default Figure 5-7 – Default Wood Door Head Jamb and Side Jamb Figure 5-8 – Default Door Sill
Equation 5-3 Where Ut = Total door system U-factor Utr = Top rail U-factor Atr = Top rail area Ubr = Bottom rail U-factor Abr = Bottom rail area Ues = End stile U-factor Aes = End stile area Umr = Meeting rail U-factor Amr = Meeting rail area Udpc = Door core U-factor Adpc = Door panel core area Ueg = Edge-of glazing U-factor Aeg = Edge-of-glazing area Ucg = Center-of-glazing U-factor Acg = Center-of-glazing area Apt = Projected total door system area Figures Figure 5-11 – Garage Door U-factor Area Weighting, Sectional Figure 5-12 – Garage Door U-factor Area Weighting, Elevation View Figure 5-13 – Garage Door Front Elevation View and Perimeter Details
Modification of Approved Framing Components and Addition of New Framing Components A. If a framing component within an approved FPL is modified, the modified component becomes a new member of the approved FPL without additional validation testing if the modification is consistent with the definition of framing product line. B. A new framing component may be to an approved FPL without additional validation testing if the new framing component is consistent with the definition of FPL. Total Product Rating The U-factor of a fenestration product may vary by size. In order to provide a uniform rating procedure for the comparison of fenestration systems, total product U-factor rating is calculated for the model (standard) size per Table 4-3 and Table 5-9. A U-factor rating for sizes other than standard model size can be calculated for informational purposes. Reporting of Ratings The U-factor shall be reported to 0.05 W/(m2-K) (0.01 Btu/h•ft2•°F). All variables used in the formula shall be expressed to at least three significant decimal places. Determining Thermal Transmittance (U-factor) for Sloped Glazing Systems All sloped glazing systems shall be rated for thermal performance characteristics at a slope of 20o above the horizontal (See Section 5.3 [Skylights] for more information); and Sloped glazing systems are validated at vertical position. Complex Product Rating This section provides the details of additional non-residential product and their model (standard) sizes for rating purposes. Spandrel Panel Spandrel panels shall be rated for U-factor at the size specified in Table 4-3. Configuration Details Two lites with one vertical mullion. Spandrel products shall be simulated and tested with intermediate verticals as jambs and
Table 5-8 – Center-of-Glazing Values Uc Reference Glazing System Without Film With Film Uc Btu/h·ft2·ºF Film Position Uc* Btu/h·ft2·ºF 3 mm (1/8 in) clear 1.04 Interior 6 mm (1/4 in) clear 1.02 Interior 6 mm (1/4 in) grey 1.02 Interior 3 mm (1/8 in) clear 3 mm (1/8 in) clear 7mm (1/4 in) gap 0.55 Interior 6 mm (1/4 in) clear 6 mm (1/4 in) clear 12.7mm (1/2 in) gap 0.47 Interior 6mm (1/4 in) grey 6 mm (1/4 in) clear 12.7mm (1/2 in) gap 0.47 Interior * Uc ‘with Film’ shall be calculated using reference glazing with film to be rated. Table 5-9 – Values of U-factor for Reference and Applied Films Reference Product U-factor Btu/h·ft2·ºF Operator Type Reference Reference Glazing no film with film* Residential Fixed Aluminum 3mm (1/8 in) clear 1.081 Non-Residential Window-wall Aluminum 6mm (1/4 in) 1.021 6mm (1/4 in) grey 1.021 Residential Fixed Aluminum 3mm (1/8 in) clear 3mm (1/8 in) clear 7mm (9/32 in) gap 0.700 Non-Residential Window-wall Aluminum 6mm (1/4 in) clear 6mm (1/4 in) clear 12.7mm (1/2 in) gap 0.588
V Validation Testing xii, 9, 85 Visible Transmittance ii, 8 W Wall Glazed 93 Weather Strip 11 Window xiii, 7, 71, 82, 97 Fixed xiii, 96 Wall 7, 71 Wood x, xii, 49, 50, 54, 91