Case Studies in Existing Building Audits Erica Brabon Steven Winter Associates, Inc. 307 7 th Ave., NY, NY ebrabon@swinter.com
Who we are Steven Winter Associates, Inc. (SWA) is a 37 yearold architecture and engineering consulting firm specializing in building performance. SWA has trained over 2000 managers, architects, engineers and maintenance staff on how to run and maintain multi-family buildings in the last five years SWA works with many other types of high performance buildings including Energy Star, LEED, Building America, PATH, and numerous regional performance specifications. Offices: Norwalk, CT; NYC, NY; Washington DC
Peter Cooper Village and Stuyvesant Town Built in the late 40 s No insulation in the walls 11,232 units 11,635,040 total square footage 56 buildings, 110 addresses over 86 acres Maintenance team of 264 people The property ranges from 4-6 Btu/ft²/HDD* Average NYC buildings operate at 14 Btu/ft²/HDD PCVST apartments use 280 kwh/month *Btu/ft²/HDD or British Thermal Units/Square Feet/Heating Degree Day is a measurement through which buildings are compared regardless of size or geographic location.
How do you audit an energy efficient building? Visit a sampling of apartments I personally went to 125 apartments No hole is too small Building psychology Energy use index 25% for DHW 280 kwh per month per apartment 29 Therms per apartment Tight building envelope with good windows What about moisture?
Energy Modeling Where Do We Begin? 2 Complexes 11,232 Apartments 110 Building Addresses 56 Structures Programmatic Considerations
Energy Modeling STEAM 18 Steam Plants 18 Steam Meters Model by Heating Plant ELECTRIC 63 Meters (kwh) 2 for Demand GAS 126 Meters WATER 5 Meters
Energy Modeling Conclusions Models 18 Benchmarks 2 Scope of Work 2 NYSERDA Reports 1
Energy Modeling and Data Other Considerations Renovations EMS Installation Thermostatic Setpoints Appliances & Fixtures Air Conditioning Ventilation Domestic Hot Water Water
What d we come up with? Low-flow aerators and showerheads Upgrades to ventilation and in some cases adding ventilation Air sealing Energy efficient lighting Motion sensors Bi-level lighting Energy Star appliances Each property could cut energy usage by 21%
Green Measures at PCVST Switched to green cleaning products Integrated pest management Best maintenance team we ve ever worked with Native and adaptive plants Green Market in the Oval
380 Unit Coop 5 different floor plans Many decision makers as opposed to one decision maker Ranked in the 35 th percentile of energy performance Using NYSERDA s benchmarking tool 3 boilers and a central chiller
Lots of Room for Improvement Low-flow faucet aerators and showerheads Recommended but hard to do in a coop Energy efficient lighting and appliances Again, hard to implement in-unit measures Upgrade and balance the ventilation system Integrate a heat recovery system Air sealing Tuning and programming the existing boiler controls Thermostatic controls in the elevator room Replace the undersized cooling tower Possible candidate for Combined Heat & Power
What about smaller buildings?
6 Small Buildings in Brooklyn 6 small affordable housing buildings All 15-16 units Same owner Same atmospheric gas boilers in every one All gut rehabbed in the late 80 s
Same Audit process Visiting apartments Interviewing staff and tenants Find the person who s worked there the longest Benchmarking Combustion efficiency testing Air leakage testing
Air Leakage Compartmentalization
Same Scope of Work Air sealing Very common energy efficiency measure Energy efficient lighting and appliances Boiler replacement Fix the existing controls Upgrade roof insulation Low-flow aerators and showerheads
Why not atmospheric gas? Inefficient Loses energy both on and off Cannot control draft Draft losses increase on cold days Very susceptible to backdrafting, spilling DANGEROUS Typically poorly installed, maintained Modular setup is not modular; one appliance
2 Story Garden Style Building 1987 refrigerators and heat pumps Kitchen, laundry and bath venting into the attic Old commercial kitchen ventilation not sealed off Moisture damage throughout the building No controls for the boiler 100% outdoor air T12 and Incandescent lighting
Possible Scope Replace all refrigerators and heat pumps Combine groups of attic vents and vent through the roof AIRSEAL Properly decommission commercial kitchen equipment Airsealing and fixing the ventilation will fix moisture problem and save energy Energy recovery Full lighting retrofit
Conclusion You can always find ways to increase efficiency Talk to the tenants and maintenance staff Building psychology Investigate all possible funding opportunities for the owner Know when to call in the experts
Thank you! Questions? Erica Brabon ebrabon@swinter.com