scope:

Products and Effects Covered

A. Products of all frame materials including (but not limited to) aluminum, steel, thermally broken aluminum, wood, vinyl, reinforced vinyl, fiberglass, and plastic, used independently or in combination;

B. Products of all operator or unit types including (but not limited to) vertical sliding windows, horizontal sliding windows, casement windows, projecting windows, fixed windows, non-standard shaped windows, glazed wall systems, glazings for site built fenestration products, bay or bow windows, skylights, and vehicular (garage/rolling) access doors (with or without glazed areas);

C. Single or multiple assemblies of exterior doors;

D. Products of any size;

E. Products of all glazing materials, tints, and types, including (but not limited to) clear glass, tinted glass, laminated glass, dynamic glazing product, thin plastic films (internally suspended, internally applied, or externally applied), rigid plastics with or without any solar control, low-E, or any other partially transparent coating;

F. Products with any or no gap width between glazing layers;

G. Products with any gas-fill between glazing layers, including (but not limited to) air, argon, krypton, CO₂, or mixes of these gases;

H. Products with any spacer or spacer systems between glazings, including (but not limited to) metallic, non-metallic, or composite spacers;

I. Products utilizing any and all glazing dividers, including (but not limited to) interior, exterior, or between glazing grilles, muntin bars, caming, true divided lites, simulated divided lites, or simulated caming bars;

J. Products designed for installation at any tilt; and

K. "Film" attachment products that consist of a flexible adhesive-backed polymer film which may be applied to the interior or exterior surface of an existing glazing system in an installed fenestration product (i.e., as a retrofit, 'field-installed,' or 'daylight-installed').

[Note: Films factory-applied to glazing prior to fenestration product fabrication and installation are already covered as glazing options by NFRC 200 and shall not be rated according to the procedure of Section 5.7]

Internal shading systems are included in 2.1.1A and shall be tested in accordance with NFRC 201.

Products Covered Using NFRC 201 Test Procedure for SHGC

Products not covered by NFRC 200 simulation techniques and that are covered by test-only procedures are as follows:

A. Products with shading systems between the glazing layers of the fenestration aperture;

B. Products with non-specular transmittance and reflectance properties, including (but not limited to) translucent fiberglass and glass blocks;

C. Fenestration systems whose glazing departs from being parallel, such as with curved glazing, complete bay windows, corrugated or patterned glazing, or glazing blocks (fenestration systems made up of combinations of complete windows or doors each of which individually meets the requirements in Section 2.1 can be included by treating each of the windows or doors separately);

D. Tubular daylighting devices;

E. Garden or greenhouse windows;

F. Adhesive-backed film products with non-specular transmittance and reflectance properties, including (but not limited to) opaque, textured, translucent, or 'frosted' films;

G. Adhesive-backed film products with non-uniform properties across their surface, including (but not limited to) patterned films; and

H. Dynamic attachment products for swinging doors.

Products and Effects Not Covered

Products and Effects Not Covered (SHGC) It is the intent of this procedure to add the following products to the scope once a solar heat gain test procedure and/or advanced calculation methods have been developed (this may be accomplished through the issuance of a technical interpretation, addendum, and/or by a revision to this document).

A. Products with shading systems attached to the outside of the fenestration aperture;

B. Solar heat gain performance changes of a fenestration product over the course of time, i.e., long-term energy performance;

C. Fenestration systems with angular selectivity that is with optical properties, though specular on the small scale which produce emerging rays whose angle of transmittance is not equal to the angle of incidence, measured with respect to the normal to the plane of the fenestration aperture

D. Adhesive-backed film products with light-redirecting properties--that is with optical properties which produce one or more transmitted beams where the direction of the transmitted beam is not equal to the incident direction, including (but not limited to) holographic or micro-structured films; and

E. Adhesive-backed film products incorporating materials with optical properties that vary in response to ambient conditions (chromogenic), such as electrochromic, thermochromic, and photochromic materials.

Products and Effects Not Covered (VT)

It is the intent of this procedure to add the following products to the scope once a visible transmittance (VT) test procedure and/or advanced calculation methods have been developed This may be accomplished through the issuance of a technical interpretation, addendum, and/or by a revision to this document.

A. Products with shading systems, either between the glazing or attached to the inside or outside of the fenestration aperture;

B. Visible transmittance performance changes of a window over the course of time, i.e., long-term energy performance;

C. Products with non-specular transmittance and reflectance properties, such as translucent fiberglass and glass blocks;

D. Fenestration systems whose glazings depart from being parallel, such as with curved glass, complete bay windows, corrugated or patterned glass, glass blocks, etc. (fenestration systems made up of combinations of complete windows or doors, each of which individually meet the requirements in Section 2.1, can be included by treating each of the windows or doors separately);

E. Fenestration systems with angular selectivity, which is with optical properties, though specular on the small scale which produces emerging rays whose angle of transmittance is not equal to the angle of incidence, measured with respect to the normal to the plane of the fenestration aperture; and

F. Tubular daylighting devices.

PURPOSE

To specify a method for calculating solar heat gain coefficient (SHGC) and visible transmittance (VT) at normal (perpendicular) incidence for fenestration products containing glazings or glazing with applied films, with specular optical properties calculated in accordance with ISO 15099 (except where noted) or tested in accordance with NFRC 201.

[Note: This standard specifies a method for calculating the solar heat gain and visible transmittance from direct solar radiation through most fenestration products at normal incidence only. This procedure is limited to normal incidence calculations because solar optical data needed for such calculations is typically only available at normal incidence. While solar radiation rarely enters a fenestration product at normal incidence, SHGC and VT at near normal angles of incidence (less than 30^o off normal) are typically very similar to those at normal incidence; for other angles, the SHGC and VT at normal can be used, to first order, as an indicator of the relative magnitude of solar heat gain (SHG) and VT.]