North Carolina Energy Conservation Code: The Future of Residential Requirements

Transcription

1 North Carolina Energy Conservation Code: The Future of Residential Requirements Margie Meares Mathis Consulting Company MC 2 Asheville, NC mmeares@gmail.com Conducted by: Jeff Tiller, PE, LEEDAP Appalachian State University Dept. of Technology & Energy Center Boone, NC

2 What We Will Cover Today (1) Introductions Who we are Governor s Initiative Current Status of the NC Energy Code Highlights of the 2009 NC Energy Code

3 What We Will Cover Today (2) Highlights of the 2009 IECC and a look into Margie & Jeff s Crystal Ball to see what NC next code might be.

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5 Who is Mathis Consulting? Building science and research firm for over 25 years Founding director of NFRC Building science educators (EEBA, NAHB, RCI, CSI, AIA, NFRC, etc.) Code development (ASHRAE, IECC, etc.) Building science education for the public Board of REALTORS

6 Appalachian State University s Energy Center State Energy Plan Ad Hoc Energy Code Committee of NC Building Code Council Department of Energy s Building America contract Hundreds of building-related workshops and consulting projects NC s first Zero Energy Home Passive Solar Planbook Check us out at

7 Governor Easley s Initiative July 2008 NGA grant to provide training to building code officials on NC Energy Codes September 9, 2008 GOV. EASLEY ANNOUNCES STATE RECEIVES FEDERAL ENERGY GRANT Funds Will Be Used To Develop Building Codes To Save Fuel And $40 Million Yearly

8 Total Energy Use by Sector (TBtu) Transportation Industrial Residential Commercial Transporportation 27% 2004 Commercial 20% Transpor -tation 28% Industrial 27% Commercial 7% Residential 26% Industrial 36% 1960 Residential 29%

9 Buildings Matter! A 30% improvement in US building efficiency would reduce energy bills by $75 billion in 15 years and eliminate the need for 80 new nuclear power plants over the next 20 years. Source: DOE Office of Energy Efficiency and Renewable Energy and we can get 30% more efficiency in our sleep!

10 Moving A Market Laws, Codes, Regulation PUSH PULL Education, Marketing, Advertising, Incentives, etc. Note: The primary friction in the system is resistance to change

11 What is the Code? Least safe Least strong Least energy efficient building allowed by law.

12 Where do Codes Come From?

13 Disaster Breeds Codes The Chicago Fire 1871 AD Destroyed 17,000 buildings, killed 250 people, left 100,000 homeless. Bankrupted the insurance industry New code adopted in 1875 regulating building construction and fire prevention.

14 More Recently

15 Katrina s Legacy Hurricane Katrina 2005 AD Costliest hurricane in history est. $80 billion Over 1300 confirmed deaths 3200 still missing Louisiana and Mississippi? Just considering their first Building Code!

16 What About Energy Codes? Disaster is not as easy to define Pain is relative $3 per gallon gasoline? $6? $10? $0.15 per kwh electricity? $0.25? $0.50? $60 per barrel of oil? $80? $100 $150?

17 Drought

18 Income and Utility Bills Household Income Average Annual Energy Bill Energy Bill as % of Income Under $10,000 $1,350 18% $10,000 to $25,000 $25,000 to $50,000 $50,000 to 75,000 $1,300 7% $1,400 4% $2,100 3% $75,000 over $2,700 3%

19 What Does The State Do? State s interest in protecting citizens, property, coasts, water, etc. We rely on the Code to handle this, right?

20 OUR NC Energy Code Born from the Model Codes 2003 IECC is the Base NC-Specific Changes Adopted in 2006 New Code 2009 NC Energy Code 2006 IECC is the Base Can be used starting Jan. 1, 2009 Mandatory on July 1, 2009

21 2006 NCECC based on the 2003 IECC and the 2004 supplemental Let s consider some important features of the current code

22 RECA Guides: NC Page 2

23 Fenestration Performance Section NFRC Rating for all Manufactured Fenestration U-factor SHGC Air Leakage OR Default Tables (1)(2)(3) Note: Default Tables ONLY work on performance path!

24 Solar Heat Gain Coefficient Section Mandatory Requirements The combined solar heat gain coefficient (the area-weighted average) of all glazed fenestration products (including the effects of any permanent exterior solar shading devices) shall not exceed 0.4.

25 Component Trade-off Approach Whole building performance must be better than or equal to the minimum Allows Trade-offs between components (with some exceptions) SHGC of 0.4 is required for all locations Envelope requirements may not be traded off against HVAC Termite issues exempted

26 Crawl Spaces Section NC now allows unvented (insulated & sealed) crawl spaces Think of them as conditioned basements for very short people Treat them that way! Must control ground moisture with a durable vapor retarder!

27 Unvented Crawlspaces The Ground Cover is Key Crawl Space Walls: Zone 6: R-7 Zone 7: R-8 Zone 8: R-10 Zone 9: R-11 Zone 11: R-17

28 Infiltration Control Section All penetrations through the thermal envelope shall be caulked, gasketed, weatherstripped, wrapped or otherwise sealed to limit uncontrolled air movement.

29 Myth: Insulation Stops Air Leaks Some types of insulation are no more effective at stopping air and cold drafts than an umbrella is at stopping the wind

30 Sealing Air Leaks Fiberglass Insulation Does Not Work! Not an air seal Won t fully fill gap Will fall out But the 2006 Commentary says its OK if tightly packed

31 Introducing the 2009 North Carolina Energy Conservation Code Effective Date: January 1, 2009 Enforcement Date: July 1, 2009

32 What s Changed Since NCECC 2006? Stringency differences are small and local Format completely new New climate basis Strictly geographical (no more HDD) Fewer zones (more homogeneity within jurisdictions) Better climate coverage (zones based on more than HDD) Residential/Commercial use the same zones

33 2006 IECC Climate Zones: Zones 4 and Below Don t Require Wall Vapor Barriers (Only NW Mountains need one)

34 2009 NCECC 5 4 3

35 What s Changed Since IECC 2003? (cont d.) Key differences Single-family and multifamily consolidated Envelope requirements independent of windowwall ratio in prescriptive path Performance path cleaner, more complete, closer to prescriptive Additions much simpler New hard limits (aka trade-off limits ) for glazing U-factor/SHGC Duct R-value (8) cannot be traded off Prescriptive requirements given in purchasable units (e.g., R-value, not U-factor) Requirement to seal air handler

36 Coming Up 2009 Energy Code Climate Zone > 3 4 except Marine 5 and Marine 4 Fenestration U-Factor Skylight U-Factor Fenestration Solar Heat Gain Coefficient (SHGC) Ceiling R-value Wood Frame Wall R-value or 13+5* Mass Wall R-value Floor R-value f Basement Wall R-value 0 10/13** 10/13** Slab R-value and Depth *** 0 5, 2 ft 10, 2 ft Crawl Space Wall R-value 5/13**** 10/13** 10/13** * Either R-19 in the wall cavity (2x6 framing) or R-13 cavity and R-5 sheathing ** Either R-10 foam that is continuous or R-13 in a cavity wall *** Add R-5 for heated slabs, such as those with imbedded radiant heating tubes **** Either R-5 foam that is continuous or R-13 in a cavity wall

37 NC Climate Zone 5 = Old Zone 11 IECC Climate Zone 5 Alleghany Avery Watauga Ashe Mitchell Yancey

38 NC Climate Zone 4 IECC Climate Zone 4 Alamance Davie Hertford Polk Alexander Durham Iredell Rockingham Bertie Forsyth Jackson Rutherford Buncombe Franklin Lee Stokes Burke Gates Lincoln Surry Caldwell Graham Macon Swain Caswell Granville Madison Transylvania Catawba Guilford McDowell Vance Chatham Halifax Nash Wake Cherokee Harnett Northampton Warren Clay Haywood Orange Wilkes Cleveland Henderson Person Yadkin

39 NC Climate Zone 3 NC Climate Zone 3 Anson Dare Mecklenburg Robeson Beaufort Davidson Montgomery Rowan Bladen Duplin Moore Sampson Brunswick Edgecombe New Hanover Scotland Cabarrus Gaston Onslow Stanly Camden Greene Pamlico Tyrrell Carteret Hoke Pasquotank Union Chowan Hyde Pender Washington Columbus Johnston Perquimans Wayne Craven Jones Pitt Wilson Cumberland Lenoir Randolph Currituck Martin Richmond

40 Coming Up 2009 Energy Code Climate Zone > 3 4 except Marine 5 and Marine 4 Fenestration U-Factor Skylight U-Factor Fenestration Solar Heat Gain Coefficient (SHGC) Ceiling R-value Wood Frame Wall R-value or 13+5* Mass Wall R-value Floor R-value f Basement Wall R-value 0 10/13** 10/13** Slab R-value and Depth *** 0 5, 2 ft 10, 2 ft Crawl Space Wall R-value 5/13**** 10/13** 10/13** * Either R-19 in the wall cavity (2x6 framing) or R-13 cavity and R-5 sheathing ** Either R-10 foam that is continuous or R-13 in a cavity wall *** Add R-5 for heated slabs, such as those with imbedded radiant heating tubes **** Either R-5 foam that is continuous or R-13 in a cavity wall

41 Standard Roof Truss Possibility of ice dam formations Ceiling insulation code requirements assume standard truss systems Cold corners contribute to condensation and mold growth

42 Raised Heel Truss Raised Heel/Energy Truss credit if insulation is full height over exterior wall R-30 instead of R-38 R-38 instead of R-49

43 NCEEC 2009 Air leakage (Mandatory) Section Building thermal envelope Shall be durably sealed Shall allow for differential expansion and contraction The following shall be caulked, gasketed, weatherstripped or otherwise sealed with an air barrier material sitable film or solid material:

44 The specifics: Site-built windows, doors and skylights Openings between window and door assemblies and their respective jambs and framing Utility penetrations Dropped ceiling or chases adjacent to the thermal envelope Floor framing under kneewalls Walls and ceilings separating the garage from conditioned spaces Behind tubs and showers on exterior walls Common walls between dwelling units Other sources of infiltration

45 Sealing Chases Seal duct penetrations and between OSB panels and framing with caulking, mastic, or foam Foam Mastic

46 Sealing Chases Make sure the whole chase is sealed (around the duct and between the lid and the framing)

47 Fire Blocking and Air Sealing Products

48 Air Sealing Pre-Insulation Seal rough openings with caulk, backer rod or special foam

49 Air Sealing Pre-Insulation Seal penetrations in exterior wall sheathing

50 Knee Walls Need Blocking Blocking between joists needed to prevent air in attic from flowing under bonus room floor

51 Blocking & Sheathing Block stud cavities at changes in ceiling height

52 System Air Sealing Is Required Section All ducts, air handlers, filter boxes shall be sealed. Joints and seams shall comply with NC Mechanical Code

53 Seal with Durable Materials

54 Sealing Flex-duct Collar with Mastic Plastic strap Attach flex-duct to take-off collar with strap

55 Sealing Flex-duct Collar with Mastic Apply mastic to seal flex-duct to collar and collar to plenum

56 Sealing Flex-duct Collar with Mastic Pull outer liner over sealed take-off; strap

57 NOW Introducing the 2009 International Energy Conservation Code (IECC) NC Effective Date:??? NC Enforcement Date:???

58 Ducts Require ducts be tested OR brought entirely into conditioned space. Estimated energy savings 8% or better.

59 Lighting Require 50% of lamps in new homes be high efficiency (CFL or equivalent) Estimated energy savings 4%

60 Southern Windows Lower max fenestration (window) U- factors in zones 2 to 4. Exception for impact glazing. (est. 1% to 2%) Lower max fenestration (window) SHGC to 0.30 in zones 1 to 3 (IECC) (est. 1% to 2%) Lower max fenestration (window) SHGC to 0.35 in zones 1 to 3 Exception for impact glazing. (.5% to 1%) Which will it be in NC?

61 Air Seal & Insulation Installation Quality Require blower door OR visual inspection for air seal and insulation installation.

62 Air Sealing & Insulation Installation Quality Require blower door OR visual inspection for air seal and insulation installation. Require gasketed fireplace doors & external combustion air.

63 Basement Insulation Add an R-5/13 basement R-value in zone 3 with exemption for warm humid locations.

64 Equipment Efficiency Remove equipment efficiency tradeoffs from performance calc. We already do this in North Carolina

65 Back to the Future The Governor s Proposal DOE's 30% Residential Codes Initiative Education and Enforcement

66 Continuous Improvement Training Tools Enforcement Continuous Improvement

67 What other code improvements do we go after?

68 Testing