Roofing Retrofits: Focus on Sustainability

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1 Roofing Retrofits: Focus on Sustainability TM James L. Hoff, DBA Research Director Center for Environmental Innovation in Roofing TM Center for Environmental Innovation in Roofing

2 Why Sustainable Roof Retrofits? Few Major Building Systems Offer As Many Energy & Environmental Benefits And Few Major Building Systems Are Installed as Frequently as Roofs

3 Sustainable Roof Retrofit Benefits Increased Energy Efficiency Reduced Global Warming Cleaner Air & Water Reduced Material Waste Extended Building Life Cycle Renewable Energy Production Increased Health & Well-Being

4 The Roof Retrofit Multiplier Effect: 1 Billion Sq. Ft. New Roofing Re-Roofing / Retrofit 3 Billion Sq. Ft. North American Low-Slope Roofing Market (Billions of Square Feet, 2006) Each year, 3 billion square feet of commercial roof retrofits are installed in North America, exceeding new commercial roof installations by 3 to1! Data Source & Graphic by TEGNOS Research, Inc. (2008)

5 Sustainable Roof Retrofit Strategies Energy Benefits 1. High R Roofs 2. Cool Roofs 3. Rooftop Energy Production 4. Roof Daylighting 5. Rooftop Water Management 6. Roofing Material Management 7. Roof Life Cycle Management Environmental Benefits

6 High R Roofs

7 What is a High R Roof? A High R Roof is a roof that provides a level of thermal resistance (R) substantially higher than current minimum standards and practices. Center For Environmental Innovation In Roofing Knowledge Center

8 Why High R Roofs? Globally: Locally: Most effective way to reduce global greenhouse gas emissions Increasing incentives available Established economic payback

9 Minimum Roof R Standards Minimum R-Values: Low-Slope Commercial Roof Insulation ASHRAE Climate Zone Typical City Example Miami Houston Atlanta Baltimore Chicago Milwaukee Minneapolis Old ASHRAE New ASHRAE First upward revision in roof R values since 1972 Source: American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE): Standard 90.1 Energy Standard for Buildings Except Low-Rise Residential Buildings, 1999 and 2007 versions.

10 High R Roofs LEED: The High R Future is Now The most recent version of LEED (v3) requires total building energy savings over ASHRAE from a minimum of 8% up to a maximum of 48% For the roof to contribute its fair share to the energy savings, R-values must be increased above ASHRAE minimums Source: US Green Building Council (USGBC): LEED v3 (2009)

11 LEED Energy Savings Targets LEED Points Existing Building Energy Savings Target 2 8% 12% 16% 20% 24% 28% 32% 36% 40% 44% 1. Source: US Green Building Council (USGBC) :LEED v3 (2009) Credit EA Energy savings above baseline of ASHRAE

12 LEED Targets & Equivalent Roof R Value LEED Points 1 Existing Building Energy Savings Target 1 Existing Building Equivalent Roof R-Value* % 12% 16% 20% 24% 28% 32% 36% 40% 44% * Roof R-Value Needed to Achieve Proportional Energy Savings 1. LEED v3 (2009) Credit EA 1. Chart is applicable for buildings within ASHRAE Climate Zones 2 through 7 - from Houston, Texas to Minneapolis, MN. Target energy savings and proportional roof insulation R-values will be lower in Zone 1.

13 High R Roofs Calculating the Savings NRCA EnergyWise Online Roof Calculator Source: National Roofing Contractors Association (NRCA): EnergyWise Online Energy Calculator

14 High R Roofs Energy Efficient Commercial Building Tax Part of 2008 Energy Extension & Improvement Act Applies to new or existing buildings Available through 2013 Deduction A partial $0.60 / sq. ft. deduction is available for building envelope improvements, of which roofing is a part The deduction is available for private and public projects: Private Project: The building owner may receive the deduction Public Project: The building designer may receive the deduction (1) (1) IRS Notice

15 High R Roofs Other High R Roof Strategies Install roof insulation in multiple, staggered layers Use non-thermal bridging techniques to attach the insulation Install a durable cover board to minimize damage to the thermal insulation Install roof walkways to protect the insulation and direct roof traffic. Top Layer Staggered Bottom Layer Top Layer Adhered Bottom Layer Fastened Cover Board Top Layer Bottom Layer Walkway Cover Board Top Layer Bottom Layer

16 Cool Roofs

17 What is a Cool Roof? A cool roof interacts with solar radiation to reduce solar heat transfer from the roof into the building and reduce ambient air temperatures above the roof surface. Center For Environmental Innovation In Roofing Knowledge Center

18 How Cool Roofs Work Solar Reflectance Thermal Emittance Thermal Mass Transpiration Convection Thermal Resistance Graphic by Center for Environmental Innovation in Roofing

19 Why Cool Roofs? Building Energy Savings: Reduced Peak Energy Needs: Heat Island Reduction: State & Local Incentives: $ Greenhouse Gas Offset:

20 Cool Roofing Options Cool Reflective Roofs Solar Reflectance Index (SRI) 0 to 100+ Solar Reflectance (SR) 0 to 1 Thermal Emittance (TE) 0 to 1

21 Cool Reflective Roofs Cool Reflective Roof Materials Cool Membranes Cool Coatings Cool Metal Cool Shingles & Tile

22 Cool Reflective Roofs Reflective Roof Standards Standard Roof Slope Initial SR (Min.) 3-Year Aged SR (Min.) Minimum SRI California Title 24 Low Slope Steep Slope n/a n/a * 10 16* LEED 2009 Low Slope n/a n/a 78 Steep Slope n/a n/a 29 ASHRAE Energy Star Low Slope Only Low Slope Steep Slope n/a n/a n/a * 3-Year Aged Value

23 Reflective Roof Standards Finding Reflectivity Data EPA Energy Star Provides reflectivity data as reported by roofing manufacturers Reports initial and aged SR only Available on-line at Cool Roof Rating Council Provides third-party certified reflectivity data for registered products Reports initial and aged SR, TE and SRI Available on-line at

24 Cool Reflective Roofs Performance, Appearance, Maintenance Independent field studies conducted by several regional roofing associations 1 suggest 3-5 year reflectivity remains within current industry standards Inadequate roof drainage and local atmospheric conditions may seriously compromise reflectivity Aesthetic appearance may be compromised even when reflective performance is maintained, especially in low-slope roofing applications Building owners should seek maintenance recommendations from the roofing material manufacturer. NOTE: Some cleaning procedures may damage roof surface and compromise useful service life 1. Midwest Roofing Contractors Association (MRCA): 5-Year Weathering Study of Field-Applied Cool Roof Coatings; Western States Roofing Contractors Association (WSRCA):4-Year Weathering Study for Cool Single-Ply Roofing Membranes.

25 Cool Reflective Roofs Calculating Energy Savings DOE Cool Roof Calculator Department of Energy online Cool Roof Calculator My State My City My Proposed Roof R-Value Solar reflectance, SR [%] Infrared emittance, IE [%] My Energy Costs and Equipment Efficiencies Summertime cost of electricity [$/KWh] Air conditioner efficiency (COP) Heating fuel cost [$/Therm] Heating system efficiency [fraction] Net Savings [$/ft 2 per year] Cooling Savings [$/ft 2 per year] Heating Savings (Penalty) [$/ft 2 per year] Select a state Select a city

26 Cool Reflective Roofs Calculating Energy Savings For Constant Electricity Rates: Use the DOE Cool Roof Calculator ( For Peak Electricity Rates: Use the DOE Cool Peak Calculator ( ) Important Note: Consider using an aged reflectivity value (approximately 50%) so that long-term energy savings are not overstated.

27 Cool Roofing Options Cool Roof Alternatives Cool Vegetation Cool Ballast Cool Colors A Traditional Alternative Using Transpiration & Thermal Mass An Emerging Economical Alternative Using Thermal Mass An Aesthetic Alternative

28 Cool Roofs Financial Incentives State & local incentives currently available: AZ, CA, CO, FL, ID, NC, NJ, NY, SC, TX Find out more from the Cool Roof Rating Council Cool roofs may be used as part of the building envelope partial deduction within the Energy Efficient Commercial Building Tax Deduction

29 Rooftop Energy

30 Why Rooftop Energy? Direct Access to Sun and Wind Low Cost Energy Real Estate Out of Sight, Secure Location Close to the Customer Close to the Grid Federal, State & Local Incentives

31 Rooftop Energy Available Technologies Photovoltaic (PV) Conventional / Roof-Mounted Thin-Film / BIPV Solar Thermal Combined PV / Solar Thermal Roof-Mounted Wind Turbines

32 Rooftop Energy Economic Trends Material costs are falling 30% Federal Investment Tax Credit is in place through 2016 Many local electric utilities are offering incentives and rebates Growth could be explosive as soon as financial markets become unfrozen

33 Rooftop Energy Local Incentives Check out the incentives in your state: all at one Web site: Database of State Incentives for Renewables and Efficiency (DSIRE)

34 Roof Daylighting

35 Why Roof Daylighting? Easy to install in new construction or re-roofing Proven energy savings High return on investment

36 Roof Daylighting Current Technologies Passive Systems Capture, Reflect & Direct Daylight Active Systems Follow the Sun to Maximize Sunlight Capture Integrated Systems Combine Solar and Electric Lighting in an Integrated Package

37 SkyCalc 2.0 Roof Daylighting Design Tool Available from Free download Comes with weather data for 48 locations in the USA Identifies skylighting strategies to achieve optimal lighting and HVAC energy savings for a building Uses relatively simple data inputs to describe the building Calculates energy impacts and produces graphs and charts that describe annual energy-use patterns

38 Roof Daylighting Current Incentives Daylighting may be used as part of the building lighting partial deduction within the Energy Efficient Commercial Building Tax Deduction Many state & local incentives available

39 Rooftop Water Management

40 Why Rooftop Water Management? Reduced storm water runoff Improved water quality in rivers and lakes Many water management options are also cool roofs

41 Storm Water Runoff Storm Water and Combined Sewer Overflows Combined sewer system are remnants of the country's early infrastructure and are typically found in older communities. Combined sewer systems serve roughly 772 U.S. communities, or about 40 million people.

42 Rooftop Water Management Water Management Options Vegetated Options (Green Roofs) Non-Vegetated Options (Blue Roofs) Hybrid Options (Blue-Green Roofs)

43 Rooftop Water Management Vegetated (Green) Options INTENSIVE GREEN ROOFS EXTENSIVE GREEN ROOFS Heavy Weight Very Heavy Weight Lightweight Moderate Weight Plants & Shrubs Shrubs & Trees Soil Sedum Media Flowering Plants Soil Soil Root Barrier / Drainage Mat Insulation Roofing / Waterproofing Membrane Root Barrier / Drainage Mat Insulation Roofing / Waterproofing Membrane

44 Rooftop Water Management Non-Vegetated (Blue) Options Non-Modular System Modular System Ballast Moisture Retention Mat Drainage Board Roofing Membrane Ballast Interlocking Drainage Tray Roofing Membrane

45 Rooftop Water Management Hybrid (Blue-Green) Option Ballasted Areas Hold Water for Vegetated Areas and Improve Wind, Fire & Traffic Resistance Vegetated Areas Transpire and Clean Storm Water Tapered Roof Insulation Design Directs Storm Water

46 Roofing Material Management

47 Why Roofing Material Management? Annual U.S. Landfill Waste 160 Million Tons Of Construction Waste 40 Million Tons of Roofing Waste 25%+ of Total Construction Waste Source: US EPA (1998)

48 Roofing Material Management Recycling Options Asphalt Shingles / Wood Shakes: Local and regional recyclers are developing roof recycling programs. Single-Plies: Several roofing manufacturers and trade associations have initiated recycling pilot programs for some single-ply membranes. Metal Roofing: The metal industries have well-established recycling programs. Insulation: Recycling: A new organization has started a successful national recycling program for foam insulation boards Reuse-in-Place: If moisture is controlled, many varieties of roof insulation boards may be reused.

49 Roof Life Cycle Management

50 Why Roof Life Cycle Management? Increase Sustainable Service Life Roofing system Entire building Reduce Environmental Impacts Reduce solid waste from unnecessary re-roofs Eliminate leak-related toxins (mold, micro-organisms) Maintain roof energy-efficiency (eliminate wet insulation, restore soiled roof surfaces)

51 Roof Life Cycle Management The All-Too-Common Roof Life Cycle Acquisition 1 Acquisition 1 End-Of-Life 2 End-Of-Life 2 High Impact Use Use Low Time Reduced Service Life Accelerated Replacement Cycle Increased Financial & Environmental Impact 1. Acquisition includes raw material extraction, manufacturing, transport & installation 2. End-of Life includes removal & disposal

52 Roof Life Cycle Management The Sustainable Roof Life Cycle Acquisition 1 Planned Maintenance Renewal / Renovation End-Of-Life 2 High Impact Extended Use Extended Use Low Time Extended Service Life Planned & Orderly Replacement Cycle Reduced Financial & Environmental Impact 1. Acquisition includes raw material extraction, manufacturing, transport & installation 2. End-of Life includes removal, disposal and recycling

53 Important Life Cycle Management Tips Identify critical service functions and countermeasures before selecting a roof design Design with the end in mind Use roof commissioning as an assessment tool Plan (and budget) for at least one major renovation or renewal of the roof

54 Center for Environmental Innovation in Roofing 816 Connecticut Ave, NW Washington, DC