Benefits of Interior Installed High Performance Insulating Glass for Commercial Retrofit Applications – A Case Study

1. BENEFITS OF INTERIOR INSTALLED HIGH PERFORMANCE INSULATING GLASS FOR COMMERCIAL RETROFIT APPLICATIONS – A CASE STUDY WDMA Technical Conference Chicago, IL 28 June 2016

2. Outline of discussion • Introduction & Background – 400 Market Street, Philadelphia PA, USA • System Description – Interior Installed Low-e Insulating Glass • Test Configuration & Conditions • Energy Comparison • Surface Temperature Comparison • Cost Comparison • Conclusions

3. Introduction & Background • 400 Market Street, Philadelphia PA • 12-story office building • Constructed in 1971 with monolithic clear glazing • After market window film applied to interior lites • Prepared By: Home Innovation Research Labs Funded by U.S. Department of Energy, Project #DE-­‐EE0004015 • Presentation prepared collaboratively between Quanex Building Products and JE Berkowitz LLC

4. Interior Installed Low-e IGU • Interior IGU construction: • 2 lites 5 mm glass • PPG SB60 low-e coating on surface #3 • ½” (13 mm) argon glazing gap • Aluminum spacer with PIB primary and silicone secondary sealants • Mounted interior of monolithic lite • Separated by applied flexible spacer • Interior mechanical trim applied to existing sill framing

5. Interior Installed Low-e IGU • Overall system center-of-glass U-value = 0.18 Btu/hr-ft2-F (1.02 W/m2-K) • Overall system Solar Heat Gain Coefficient = 0.44

6. Test Specimen Configuration • Two pairs of side-by-side offices chosen for comparison • Room Dimensions: 10’ x 12’ (3.05 m x 3.66 m) • Glazing Dimensions: 6’ x 6’ (1.83 m x 1.83 m ) • Room pair #1 located on 6th floor facing east • Room pair #2 located on 11th floor facing north • One glazing per pair retrofitted after film removal

7. Test Conditions • Air leakage testing demonstrated minimal difference between original and retrofit energy transfer effects due to air leakage are deemed negligible • All rooms isolated from building mechanical (HVAC) systems • Independent heating/cooling equipment in each office to maintain temperature: • Heating demand – 69 F (20.6 C) • Cooling demand – 71 F (21.7 C) • Incandescent lighting utilized to simulate thermal loads from occupants and equipment • Monitoring conducted from: Nov 2011 – Oct 2012 Heating 1 Dec 2011 – 29 Feb 2012 Cooling 27 Jul 2012 – 30 Sep 2012

8. Office Energy Use Comparison

9. Building Energy Use Comparison Energy usage based on monthly utility billing following full building retrofit

10. Building Energy Use Comparison

11. Surface Temperature Comparison

12. Installed Cost Comparison • Compares estimated cost of “rip-out and replace” (ROR) retrofit with specified double-glazed IGU to actual installed cost of internally installed low-e IGU for entire building • Does not include additional long-term savings due to triple-glazed system resultant of internally installed low-e IGU vs. double-glazed ROR. • Total Openings: 532 • Total Glazing Area: 18.9 mft2 (1759 m2)

13. Conclusions • Heating energy reductions of between 40% and 60% compared to monolithic glazing with applied film • Cooling energy savings up to 35% compared to monolithic glazing with applied film • Whole building post-retrofit total energy savings of up to 30% • Interior surface temperatures kept closer to room-side temperature year-round; greater condensation resistance in winter and cooler in summer • Less than half the cost of a ‘rip-out-replace’ full glazing replacement • Additional Benefits: • Minimize internal disruption (off hours) • No change to exterior envelope or weatherization • No scaffolding, rigging, etc. for multi-story/high-rise retrofit • Less total time for full building retrofit

14. Questions??? Tracy G. Rogers Quanex Building Products Email: tracy.rogers@quanex.com Phone: 01 603 661 4096