Push the Envelope: High-Performance Design in High-Rise Buildings

Transcription

1 Push the Envelope: High-Performance Design in High-Rise Buildings Brett Bridgeland Architect, CEM, LEED AP Seventhwave, supporting ComEd Energy Efficiency Program Allison McSherry Architect, CEM, LEED AP BD+C Klein & Hoffman C O N F I D E N T I A L Presenters Brett Bridgeland Architect, CEM, LEED AP Seventhwave, supporting ComEd Energy Efficiency Program Allison McSherry Architect, CEM, LEED AP BD+C Klein & Hoffman 2 1

2 Code: Compliance Pathways Jan. 1, 2016 IECC 2015 Mandatory Illinois State Energy Code 3 Code: Performance Improvements % -4.5% IECC % -4.5% % -8.7% IECC 2012 IECC 2015 Std

3 Code: 2015 IECC Compliance Paths Prescriptive Performance OR Comply with : C402, C403, C404 & C405 & Comply with : C406 OR Comply with : C402.5, C403.2, C404, & C & C407 Total Bldg Performance 85% V.S. Code Commissioning 5 Code: ASHRAE Compliance Paths x.1 General x.2 Definition of Compliance x.4 Mandatory Provisions x.5 Prescriptive Option x.6 Trade-Off Option 11 ECB Option App G PRM Option? x.8 Products x.7 Submittals 6 3

4 Code: Illinois Energy Conservation Code Compliance ASHRAE 90.1 User s Manual compliance forms; or COMcheck; or Comparable compliance materials approved by the AHJ; or Seal of the architect/engineer as required by Section 14 of the Illinois Architectural Practice Act, Section 12 of the Structural Engineering Licensing Act and Section 14 of the Engineering Practice Act 7 Code: Capital Development Board Projects ASHRAE is the applicable code for all CDB projects Green Buildings Act - Public Act Requires LEED, Green Globes, or equivalent LEED Silver/2 Green Globes required > 10,000 square feet Must meet highest standards but certification not required < 10,000 square feet 8 4

5 Code: Chicago Energy Conservation Code Registered Energy Professional A professional review the drawings PRIOR to submittal for building permit review C4.2.3 Urban heat island provisions (roofing) Minimum roof reflectance requirements Historic buildings Mandatory compliance unless Commission on Chicago Landmarks determines building is exempt Existing roofs Technical infeasibility variance allowed 9 Code: Compliance REP in Chicago Registered Energy Professional (REP) must stamp drawings: Must still show compliance through COMcheck, ASHRAE forms, or energy model. What about VE? Were energy savings features removed? Were the changes captured in the energy compliance documentation? 10 5

6 Code: Performance Path LEED/Green Globes Appendix G does not show code compliance Informative, not normative, appendix LEED/Green Globes currently references ASHRAE Appendix G 11 Code: Prescriptive Path Window Wall Ratio (WWR) 30%* *2 options for 40% 50/25% conditioned sq.ft. is Daylight Zone & Daylight Zoned & VT=1.1*SHGC 40% If Proposed < 40% WWR model Baseline as Proposed WWR If Proposed > 40% WWR model Baseline as 40% WWR 12 6

7 Code: Prescriptive Path Fenestration Orientation A W (A T )/4 & A E (A T )/4 or A W x SHGC W (A T x SHGC C )/4 & A E x SHGC E (A T x SHGC C )/4 ASHRAE ONLY! ASHRAE Code: Opaque Wall U-Value Climate Zone 5A Opaque Elements ASHRAE Table Assembly Maximum Nonresidential Insulation Min. R-Value IECC 2015 Table C Nonresidential Insulation Min. R-Value Roofs Insulation Entirely above Deck U R-30 c.i. R-30 c.i. Metal Building a U R-19 + R-11 LS R-19 + R-11 LS Attic and Other U R-49 R-38 Walls, Above-Grade Mass U R-11.4 c.i. R-11.4 c.i. Metal Building U R-0 + R-19 c.i. R-13 + R-13 c.i. Steel-Framed U R R-10 c.i. R-13 + R-7.5 c.i. Wood-Framed and Other Slab-On-Grade Floors U R R-7.5 c.i. R-13 + R-3.8 c.i. or R-20 Unheated F R-15 for 24 in. R-10 for 24 below Heated F R-20 for 48 in. R-15 for 36 below 14 7

8 Code: Common Mistakes Spandrel Panels Vision vs Opaque Fenestration transparent or translucent glazing materials 15 Code: Thermal Bridge Impacts Not fully addressed in the energy codes Only accounts for thermal bridging of studs Important to consider to prevent condensation R-19 batt R-9 effective R-value in 16 o.c. steel stud wall Building Envelope Thermal Bridging Guide Resource for typical constructions

9 Code: Diminishing Returns Fricklas, Richard L. Roof Insulation and Diminishing Returns. 14 May Code: Opaque Wall Improvement Costs Building Envelope Thermal Bridging Guide Appendix D 18 9

10 Code: Prescriptive - Fenestration U-Value ASHRAE Table Climate Zone 5A Fenestration Vertical Glazing, 0% 40% of Wall Nonmetal framing (all) Assembly Max. U Assembly Max. SHGC Nonresidential U-0.32 IECC 2015 Table C402.4 Climate Zone 4 Nonresidential U-factor Vertical fenestration Fixed fenestration 0.38 Metal framing, fixed U-0.42 SHGC-0.40 all Operable fenestration 0.45 Metal framing, operable U-0.50 Assembly Min. VT/SHGC 1.10 Entrance doors 0.77 SHGC Metal framing (entrance door) U-0.77 SEW 0.40 N Code: Window Performance Factors U-value Heat transmission in unit of time through unit area of a material or construction and the boundary air films, induced by unit temperature difference between the environments on each side. Solar Heat Gain Co-efficient (SHGC) The ratio of the solar heat gain entering the space through the fenestration area to the incident solar radiation. Visual Transmittance (VT) The ratio of visible radiation entering the space through the fenestration product to the incident visible radiation

11 Code: Window Frame U-Value Un-thermally broken frames typical U-values = 1.0 range. Frames with poured and debridged thermal break typical U-values = 0.65 (R-1.5) range. Frames with isobar thermal break typical U-values in 0.39 (R-2.6) range Code: COG vs. Assembly U-Value The U-factor of the total window assembly combines the insulating value of the glazing proper, the edge effects in the IGU, and the window frame and sash. The center-of-glass U-factor assumes that heat flows perpendicular to the window plane, without addressing the impact of the frame edge effects and material. Center-of-glass (COG) Typical value 0.29 BTU/ ft2-hr- F (low-e IG). Edge of Glass (EOG) Typical value 0.34 BTU/ ft2-hr- F (aluminum spacer). Frame Typical value 0.90 BTU/ ft2- hr- F (thermal break). 22 LBNL THERM 6.3/WINDOW 6.3 NFRC Manual 11

12 Code: COG vs. Assembly U-Value Area = 24ft 2 U-Value = 0.4 BTU/ft 2 -hr-f 25% reduction in performance Area = 8ft 2 U-Value = 0.5 BTU/ft 2 -hr-f 23 Code: Window Improvement Costs Building Envelope Thermal Bridging Guide Appendix D 24 12

13 Code: Glass Considerations Things to Consider Aesthetic impact Daylighting potential Occupant comfort Glare Thermal comfort Code IECC 2015 ASHRAE SHGC VT SEW = 0.40 N = 0.53 N/A All = 0.40 Assembly Min. VT/SHGC = 1.10 LBNL/DOE Tips for Daylighting with Windows 25 Envelope Commissioning Goals of ECx? Establish projects goals: OPR Improve envelope performance: Condensation Water intrusion. Energy performance. Simplify construction: Ease of constructability. Less disciplines involved. Less opportunity for installation error. Oversee mock-ups and testing: Ensure proper installation. Verify performance goals are met

14 Envelope Commissioning Design Decisions 0% Pre-Design Conceptual Design Design Development 27 Envelope Commissioning and Code ASHRAE Air Barrier Requirements Air Leakage requires a continuous air barrier: Testing Materials Assemblies NEW! Verification: Whole building air leakage testing (blower door). ECx light 28 14

15 ComEd Energy Efficiency Program New Construction Deliver high-quality education and training. Provide expert technical assistance. Offer financial incentives for implementation. Image courtesy of Gerding Edlen, photo by Steve Somen 29 ComEd Energy Efficiency Program New Construction Since buildings 113 million ft 2 completed pipeline 30 Xavier Apartments, Photo by Mark Ballogg 15

16 ComEd Energy Efficiency Program New Construction ComEd ComEd.com/BizIncentives Peoples Gas PeoplesGasRebates.com North Shore Gas NorthShoreGasRebates.com Nicor Gas NicorGasRebates.com Xavier Apartments, Photo by Mark Ballogg 31 WWR & ComEd Energy Efficiency Program 32 16

17 Useful Daylight Index (UDI) WWR UDI 40% % Impact on Electric Lighting WHOLE BUILDING ENERGY SAVINGS 85% 40% 10% WWR 34 17

18 Optimizing Views, Privacy, Light & Comfort 40% WWR 85% WWR 35 Envelope Properties - Views Photo by Seventhwave 36 18

19 Optimizing Views, Privacy, Light & Comfort John Hancock Center, Chicago 37 photo copyright: VHT Studios Optimizing Views, Privacy, Light & Comfort 38 19

20 Thermal Comfort & Operative Temperature 85% WWR 40% WWR J F M A M J J A S O N D J F M A M J J A S O N D 8am 5pm comfortable hours/year (~1/3 of those occur during evening) 39 Envelope Properties - Energy 40% WWR + Code Baseline Envelope 85% WWR + Code Baseline Envelope 85% WWR + Improved Envelope Glazing Assembly R-value Opaque Assembly R-value Envelope Average R-value Increased Conduction (Baseline) +82% +51% Solar Heat Gain Coefficient Increased Solar Gain (Baseline) +113% +59% 40 20

21 External Shading May improve comfort on south exposure. Ineffective on east/west unless extensive. Aqua Tower, Chicago, IL Minor reduction of annual energy cost. Adversely impacts passive heating. Attachment thermal bridging may offset savings (e.g. unbroken balconies). Cost prohibitive. Edith Green-Wendell Wyatt Federal Building, Portland, OR 41 First Cost Complicated Opaque assemblies can be more expensive per sq. ft. of façade: - Wind loading - Built-up vs modular - Multiple trades - Volume pricing Have to consider whole picture: - Assembly performance, including frame and attachments - Other upgrades for code compliance - Modular opaque assemblies - HVAC sizing - Elimination of perimeter heating or forced air altogether 42 21

22 Integrative Design & Next-gen HVAC Reducing cooling loads in Chicago climate unlocks next-gen HVAC. Radiant hydronic: - Pump warm/cool water through slab or panels in the space - Controls both air and surface temp - Very low fan energy & small DOAS ducts - Modest temps higher equip efficiency - Quiet - Clean interior design Passive heating & cooling 43 Integrative Design DEVELOPER O&M Cost Consultant Builder Subs Program Pro Forma Schedule Entitlements EUI Leasing / Broker Financing Incentives Energy Consultant Manufacturers MEP Engineer ARCHITECT 44 22

23 Performance Benchmarking 45 Thank You Brett Bridgeland Architect, CEM, LEED AP Seventhwave, supporting ComEd Energy Efficiency Program Allison McSherry Architect, CEM, LEED AP BD+C Klein & Hoffman 46 23