Comparison of Air Distribution Comparison of Air Distribution - PDF document

Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Comparison of Air Distribution Comparison of Air Distribution Systems Systems Underfloor Air vs. Ceiling-Based Systems 2002-2003 AE Senior Thesis Allison M Clarke Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Presentation Outline Existing Building � Existing Building & Systems & Systems � Underfloor Air Distribution Underfloor Air � Ceiling-Based System System � Comparison Ceiling-Based Conclusion & Recommendations � System Comparison Recommendation Conclusions Allison M Clarke 2002-2003 AE Senior Thesis 1

Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Project Team Existing Building Owner - Capital One Financial Corporation & Systems Underfloor Air Owner’s Rep - Jones Lang LaSalle System Ceiling-Based Architect - Ai Architecture System Comparison GC - James G. DAVIS Construction Recommendation Structural Engr - Rathgeber/Goss Associates Conclusions MEP Engr - Ai Engineering Allison M Clarke 2002-2003 AE Senior Thesis Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Architecture Existing Building & Systems Underfloor Air System Ceiling-Based System Comparison Recommendation Conclusions Allison M Clarke 2002-2003 AE Senior Thesis 2

Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Location & Site Existing Building � 1600 Scotts Crossing Road & Systems McLean, VA � 26 Acres Underfloor Air � Borders I-495 Capital Beltway System Ceiling-Based Structure System � Base Building – Floors 1 & 2 Comparison � Cast-in-Place Concrete with Post Tension Beams Recommendation � Tower – Floors 3 – 14 � Steel Structure Conclusions � Concrete Slab on Metal Deck � 18” Raised Concrete Core � Typical Floor Space Allison M Clarke 2002-2003 AE Senior Thesis Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Mechanical Existing Building � Underfloor Air Distribution System in Tower & Systems � Four 600 ton Chillers Underfloor Air � 4-Cell Cooling Tower System � Two 22,000 cfm AHU’s per Typical Floor Ceiling-Based System Comparison Recommendation Conclusions Allison M Clarke 2002-2003 AE Senior Thesis 3

Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Underfloor Air Distribution Existing Building � Background Information & Systems System Components � Underfloor Air � Construction Methods/Schedule System � Energy Use Ceiling-Based � Costs System � Lessons Learned Comparison Recommendation Conclusions Allison M Clarke 2002-2003 AE Senior Thesis Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Background Information Existing Building Alternative to conventional ceiling-based air distribution � & Systems systems Underfloor Air � Previously used for spaces with high heat loads System � Introduces air at floor level Ceiling-Based � Occupied Zone – floor to head level System � Unoccupied Zone – head level to ceiling Comparison Recommendation Unoccupied Zone Conclusions Occupied Zone Allison M Clarke 2002-2003 AE Senior Thesis 4

Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Background Information Existing Building Benefits & Systems Improved thermal comfort for occupants � Underfloor Air � Improved ventilation efficiency & indoor air quality System � Reduced energy use from mechanical systems Ceiling-Based � Reduced life cycle building costs System � Reduced floor-to-floor height in new construction Comparison � Improved occupant satisfaction and productivity Recommendation Conclusions Allison M Clarke 2002-2003 AE Senior Thesis Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Background Information Existing Building Barriers & Systems � New & unfamiliar technology Underfloor Air � Perceived higher costs System � Lack of information & design guidelines Ceiling-Based Limited applicability to retrofit construction � System � Problems with applicable standards & codes Comparison � Problems with spillage and dirt entering underfloor plenum � Concerns of condensation and dehumidification problems Recommendation Conclusions Allison M Clarke 2002-2003 AE Senior Thesis 5

Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction System Components Existing Building Typical Floor & Systems Two 22,000 cfm AHU’s � Underfloor Air � 28 fan powered terminal boxes supply System perimeter � Static pressure sensors Ceiling-Based System � 22,500 sf Access floor panels � Passive & VAV floor diffusers Comparison Source: Tate Access Floors Recommendation Conclusions Typical Mechanical Room Section Allison M Clarke 2002-2003 AE Senior Thesis Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Construction Methods/Schedule Existing Building � Local Jurisdiction Code Requirements & Systems � Underfloor is a plenum Underfloor Air System � Supply Air Diffusers Ceiling-Based � Redundant installation System � Underfloor Air Space Comparison � Moisture concerns Recommendation � Above Ceiling Air Space Conclusions � Suspended ceiling not absolutely necessary Allison M Clarke 2002-2003 AE Senior Thesis 6

Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Construction Methods/Schedule Existing Building Typical Floor Schedule & Systems Underfloor Air System Ceiling-Based System Comparison Recommendation Conclusions 219 Work Days Allison M Clarke 2002-2003 AE Senior Thesis Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Construction Methods/Schedule Existing Building Tower Schedule & Systems Underfloor Air System Ceiling-Based System Comparison Recommendation Conclusions 289 Work Days Allison M Clarke 2002-2003 AE Senior Thesis 7

Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Energy Use Existing Building Typical Floor Design Loads & Systems Typical Floor Load Total Tower Load Underfloor Air (tons) (tons) System 60 720 Ceiling-Based System Design Load Distribution Comparison 8% OA Load (tons) 10% Recommendation Lighting Load 39% (tons) Equipment Load 14% Conclusions (tons) Envelope Load (tons) Occupant Load 29% (tons) Allison M Clarke 2002-2003 AE Senior Thesis Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Energy Use Existing Building Annual Energy Consumption & Systems � Binmaker Weather Data Underfloor Air � 3,120 hours System Ceiling-Based Typical Floor Total Tower System Total Ton-hours 58,446 701,352 Comparison Recommendation Conclusions Allison M Clarke 2002-2003 AE Senior Thesis 8

Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Cost Existing Building Construction Costs & Systems $ 13.66 per square foot $ 5,136,160 Tower Cost � Underfloor Air System Operating Costs Ceiling-Based � Energy Consumption 2,912,721 kWh System � Annual Cost $ 206,803 Comparison Lifecycle Cost Recommendation � 30 years $ 9,084,118 Conclusions Allison M Clarke 2002-2003 AE Senior Thesis Capital One Northern Virginia Campus Consolidation Capital One Northern Virginia Campus Consolidation McLean, VA McLean, VA Introduction Lessons Learned Existing Building � Moisture detection in underfloor plenum & Systems Underfloor Air � Outdoor air load oversized System � 20 cfm/occupant needed Ceiling-Based � 43 cfm/occupant used System � “Green” technology Comparison � Recognized by USGBC Recommendation Conclusions Allison M Clarke 2002-2003 AE Senior Thesis 9