Curtain Wall

EFCO Corporation is a leading manufacturer of architectural aluminum window, curtain wall, storefront and entrance systems for commercial architectural applications. Headquartered in Monett, Missouri, EFCO's mission is to be the most trusted supplier in commercial architecture.  EFCO seeks to provide customers with the highest level of quality, innovation, value, and service.

With the dedication of the EFCO team and backed by the support of Apogee Enterprises, Inc., an industry leader in commercial technology, innovation and customer satisfaction, you can count on EFCO to provide the best fenestration solutions and quality service for commercial construction. Today, and in the future.

View EFCO's Corporate Overview video

Pressure Glazed & SSG



Window Wall


Solar Shades

EFCO Product Recommendations

Developed to be IBC 2018 & IECC 2018 Compliant for Climate Zones 5 & 6

The following EFCO window, storefront and curtain wall recommendations have been developed to assist owners, architects and contractors in the selection and specification of EFCO commercial fenestration solutions that meet the requirements of the IBC 2018, IECC 2018 for the Northeast.  (i.e., Climate Zones 5 & 6)  Appropriate use and application of these recommendations will vary based on performance considerations and environmental conditions unique to each project and, therefore, do not represent the final opinion or recommendation of PACE Representatives or EFCO.  Contact PACE Representatives to develop a custom fenestration basis of design (BOD) package to meet your project specific performance requirements and design conditions.

SeriesDepthSightlineThermal Performance*
(center of glass U-Factor)
 Impact Ballistic  Blast  Notes
5500X7" & 8"2 1/2"0.360.300.27NoNoNoE-Strut thermal break
5600X4 1/2"-10"2 1/4"-2 1/2"0.370.320.29YesYesYesDuracast pressure plate 
WV-4103 1/4" 1 1/16"0.390.320.28NoNoNoProject-out vent 
WV-4303 1/4"7/8" 0.420.380.35NoNoNoProject-out vent
8750XD7 1/2"3"0.350.300.27YesNoNoUnitized curtain wall 
875X--0.430.370.34NoNoNoProject-out vent
## = Series and glazing combination does not comply with IECC 2018 for Climate Zone 6
## = Series and glazing combination does not comply with IECC 2018 for Climate Zones 5 or 6
* Based on NFRC 100 gateway size and configuration (78 3/4" x 78 3/4" fixed)

Industry Insights

Code Requirements: (per IECC 2018)

The prescriptive thermal performance requirements (i.e., U-Factor) for vertical fenestration systems are indicated in Table C402.4 of the IECC 2018.  Frame material is no longer taken into account and the requirement is based on your climate zone and fenestration type.  (e.g., Fixed, Operable or Entrance Doors)

Climate Zone  5 and Marine 4              6           
Vertical Fenestration
Fixed Fenestration0.380.36
Operable Fenestration0.450.43
Entrance Doors0.770.77

Prescriptive compliance is only allowed with a vertical fenestration area less than or equal to 30% of the gross above-grade wall area.  Prescriptive compliance is allowed up to not more than 40% of the gross above-grade wall area if certain minimum floor areas are in the daylight zone and daylight responsive controls are incorporated.

U-Factors of fenestration systems (e.g., curtain wall) shall be determined by an accredited, independant laboratory in accordance with either NFRC 100 or ANSI/DASMA 105 AND labeled by the manufacturer.  Products lacking a U-Factor label shall be assigned a default U-Factor per IECC 2018 Tables C303.1.3(1)-(3).

The air leakage of curtain wall assemblies shall be a maximum of 0.06 CFM/FT2 per NFRC 400 or ASTM E 283 at 1.57 psf (75Pa).

Code Requirements: (per IBC 2018 Section 1604.3.7)

The deflection of fenestration framing supporting glass subjected to 0.6 times the Component and Cladding design pressures shall not exceed the noted deflection based on the following length of span of the framing member:

13'-6" or Less = L/175

>13'-6" = L/240 + 1/4"

Additional Resources:

Whole Building Design Guide - Curtain Wall

National Fenestration Rating Council

Wind Speed Calculator