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The Emerging Role of the Roof in a Sustainable World. Craig Silvertooth Executive Director. Dr. James L. Hoff Research Director. The Emerging Role of the Roof in a Sustainable World Why Sustainable Roofing?. Few Major Building Systems Offer As Many Energy & Environmental Benefits …
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The Emerging Role of the Roof in a Sustainable World Craig Silvertooth Executive Director Dr. James L. Hoff Research Director
The Emerging Role of the Roof in a Sustainable World Why Sustainable Roofing? Few Major Building Systems Offer As Many Energy & Environmental Benefits… … And Few Major Building Systems Are Installed as Frequently as Roofs!
The Emerging Role of the Roof in a Sustainable World Energy / Environmental Benefits • Increased Energy Efficiency • Clean Energy Production • Cleaner Air & Water • Reduced Material Waste • Extended Building Life Cycle
The Emerging Role of the Roof in a Sustainable World The Roofing Multiplier Effect New Construction 1 Billion Sq. Ft. Re-Roofing 3 Billion Sq. Ft. North American Low-Slope Roofing Market(Billions of Square Feet, 2006) Each year, 4 billion square feet of commercial roofs are installed in North America, exceeding new commercial construction by a factor of 4! Source: TEGNOS Research, Inc. 2008
The Emerging Role of the Roof in a Sustainable World Sustainable Roofing Opportunities • High R Roofs • Cool Roofs • Rooftop Energy Production • Roof Daylighting • Rooftop Water Management • Roofing Material Management • Roof Life Cycle Management Energy Environment
Sustainable Roofing Opportunities High R Roofs
High R Roofs 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 ( http://roofknowledge.org/main/energyefficientroofs/highrroofs/whatisahighrroof )
High R Roofs Why High R Roofs? Globally: Locally: • Most effective way to reduce green house gas emissions between now and 2030 • Increasing federal, state & local incentives available • Established economic payback
High R Roofs Current ASHRAE Minimum Standards Minimum R-Values: Low-Slope Commercial Roof Insulation Typical City Example Miami Houston Atlanta Baltimore Chicago Milwaukee Minneapolis “Old” ASHRAE 90.1 -1999 10 15 15 15 15 20 25 “New” ASHRAE 90.1 - 2007 15 20 20 20 20 25 30 ASHRAE Climate Zone 1 2 3 4 5 6 7 “Proposed” ASHRAE 189.1P1 20 25 25 25 25 30 35 First major increase in roof R values since 1972… … with more increases to follow soon 1 Third public review draft, May, 2009.
High R Roofs R-Value & LEED LEED 2009 (v3) New Building Energy Savings Targets (ASHRAE Climate Zones 2 through 5) ASHRAE 90.1-2007 LEED 2009 Minimum** 1 3 5 7 9 11 13 15 17 19 Energy Savings Target Baseline 10% 12% 16% 20% 24% 28% 32% 36% 40% 44% 48% Proportional Roof U-Value* 0.050 0.045 0.044 0.042 0.040 0.038 0.036 0.034 0.032 0.030 0.028 0.026 Proportional Roof R-Value* 20.0 22.2 22.7 23.8 25.0 26.3 27.8 29.4 31.3 33.3 35.7 38.5 LEED Points Available: (EA Credit 1) * Roof R-Value Needed to Achieve Proportional Energy Savings **Minimum LEED 2009 (v3) Prerequisite Source: Center for Environmental Innovation in Roofing. Note: Chart is applicable for buildings within ASHRAE Climate Zones 2 through 5 - from Houston, Texas to Chicago, Illinois. Target energy savings and proportional roof insulation R-values will be lower in Zone 1 and higher in Zones 6 and 7. For a detailed analysis of a specific building in a specific location, ASHRAE 90.1-2007 should be consulted.
High R Roofs R-Value & LEED LEED 2009 (v3) Existing Building Energy Savings Targets (ASHRAE Climate Zones 2 through 5) ASHRAE 90.1-2007 LEED 2009 Minimum** 1 3 5 7 9 11 13 15 17 19 Energy Savings Target Baseline 5% 10% 12% 16% 20% 24% 28% 32% 36% 40% 44% Proportional Roof U-Value* 0.050 0.045 0.044 0.042 0.040 0.038 0.036 0.034 0.032 0.030 0.028 0.026 Proportional Roof R-Value* 20.0 21.1 22.2 22.7 23.8 25.0 26.3 27.8 29.4 31.3 33.3 35.7 LEED Points Available: (EA Credit 1) * Roof R-Value Needed to Achieve Proportional Energy Savings **Minimum LEED 2009 (v3) Prerequisite Source: Center for Environmental Innovation in Roofing. Note: Chart is applicable for buildings within ASHRAE Climate Zones 2 through 5 - from Houston, Texas to Chicago, Illinois. Target energy savings and proportional roof insulation R-values will be lower in Zone 1 and higher in Zones 6 and 7. For a detailed analysis of a specific building in a specific location, ASHRAE 90.1-2007 should be consulted.
Sustainable Roofing Opportunities Cool Roofs
Cool Roofs 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 (http://roofknowledge.org/main/energyefficientroofs/coolroofs/whatisacoolroof)
Cool Roofs Why Cool Roofs? • Building Energy Savings • Heat Island Reduction • Peak Electricity Reduction Atlanta, GA 1972 1993 Standard Rate: Summer Peak Rate: $ $$$
Cool Roofs Where are Cool Roofs Useful? • In climates with warm, sunny summers • In areas considered Urban Heat Islands • In areas with increased peak electricity rates, demand charges, and interruptible supply agreements
Cool Roofs Cool Roofing Options LEED 2009 Cool Roofing Options1 Cool Reflective Roofs Cool Vegetated Roofs A Traditional Alternative Using Transpiration & Thermal Mass Reducing Heat Build-Up By Reflecting the Sun’s Rays 1 LEED SS Credit 7.2
Cool Roofs Cool Roofing Options LEED 2009 Cool Roofing Options1 Cool Reflective Cool Vegetated • Variety of material and color options • Little or no initial cost premium • May lose some reflectivity with age • Potential environmental benefits in addition to cool roofing • Increased weight and depth requirements • Cost premium 1 LEED SS Credit 7.2
Green Roofing Opportunities Rooftop Energy
Rooftop Energy Why Rooftop Energy? • Direct Access to Sun and Wind • Low Cost “Energy Real Estate” • Close to the Customer / Close to the Grid • Expanded Federal, State & Local Incentives • Rapidly Approaching “Grid Parity”
Rooftop Energy Current Technologies • Photovoltaics (PV) • Solar Thermal • Combined PV / Solar Thermal • Roof-Mounted Wind Turbines
Green Roofing Opportunities Roof Daylighting
Roof Daylighting Why Roof Daylighting? • Easy to install or retrofit in typical low-rise commercial buildings • Proven energy savings / high return on investment when integrated with building lighting system • Increasing federal, state & local incentives available
Roof Daylighting Current Technologies Passive SystemsCapture, Reflect & Direct Daylight Active SystemsFollow the Sun to Maximize Sunlight Capture Integrated SystemsCombine Solar and Electric Lighting in an Integrated Package
Green Roofing Opportunities Rooftop Water Management
Rooftop Water Management Why Rooftop Water Management? • Reduced storm water runoff • Improved water quality in rivers and lakes Combined sewer system are remnants of the country's early infrastructure and so are typically found in older communities. Combined sewer systems serve roughly 772 communities , home to over 40 million US citizens. Cities with Combined Sewer Systems
Rooftop Water Management Water Management Options Vegetated Options Ballasted Options Retaining Storm Water Runoff with Planting Media & Moisture Retention Mats Retaining Storm Water Runoff with Moisture Retention Mats … Plus Hybrid Vegetated / Ballasted Options Combining the best of both alternatives
Rooftop Water Management Water Management Options Vegetated Ballasted Hybrid • Possible LEED credits (SS Credits 6.1 & 6.2) • LEED cool roof credit (SS credit 7.2) • Cost premium • Possible LEED credit (SS Credits 6.1) • Low initial cost • Opportunity to optimize economics & benefits • LEED cool roof credit for 50% vegetated
Sustainable Roofing Opportunities Roofing Material Management
Roofing Material Management 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)
Roofing Material Management Current 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 programs for some single-ply membranes. • Metal Roofing: The metal industries have well-established recycling programs. • Insulation: A new organization has started a successful national recycling program for foam insulation boards
Sustainable Roofing Opportunities Roof Life Cycle Management
Sustainable Roofing Opportunities Roof Life Cycle Management • Roof Asset Management • Preventative Maintenance Programs Not only extend the roof life cycle, but the life cycle of the entire building
The Emerging Role of the Roof in a Sustainable World Sustainable Roofing Resources • Online Energy Calculators • Federal, State & Local Energy Incentives • Federal Stimulus Project Resources • Cool Roofing Resources • Renewable Energy & Daylighting Resources • Vegetated Roofs / Water Management Resources • Roof Recycling Resources • Roof Life Cycle Management Resources
Sustainable Roofing Resources Online Energy Calculators • High R Insulation & Energy Savings • NRCA “EnergyWise” (http://energywise.specright.net/) • Calculates roof energy costs per ASHRAE 90.1 • Allows comparison between roofing alternatives • Provides printable summary with charts & graphs • Cool Roofing & Energy Savings • DOE Cool Roofing Calculator (http://www.ornl.gov/sci/roofs+walls/facts/CoolCalcEnergy.htm) • Calculates annual heating / cooling savings for cool roofs • Allows comparison between roofing alternatives • “CoolPeak” option for areas with peak demand charges
Sustainable Roofing Resources Federal, State & Local Energy Incentives • Federal Tax Incentives Assistance Project • http://www.energytaxincentives.org/ • Information on Commercial Building Energy Efficiency Tax Deduction • Information on Solar Energy Investment Tax Credit • Database of State Incentives for Renewables and Efficiency • http://www.dsireusa.org/ • Covers both energy efficiency & renewable energy incentives • Includes state and local programs, including utilities • Green Roofs Tree of Knowledge • http://greenroofs.org/grtok/index.php • Covers community incentives for vegetated roofing systems
Sustainable Roofing Resources Federal Stimulus Information • Construction Stimulus Special Section • http://www.construction.com/stimulus/default.asp • Information by market sector (Federal buildings, state projects, local schools) • Sponsored by McGraw Hill • Federal Stimulus Construction Project Leads • http://www.reedconstructiondata.com/construction-project-leads/infrastructure/ • Free downloadable regional reports • Sponsored by Reed Construction Data
Sustainable Roofing Resources Cool Roofs • Cool Roof Rating Council • http://www.coolroofs.org • Third-party certifier of cool reflective roof ratings • Resource for cool reflective roofing standards & incentives • Energy Star Roof Program • http://www.energystar.gov/index.cfm?c=roof_prods.pr_roof_products • Home of EPA Energy Star cool roofing product registry • LBL Heat Island Group • http://eetd.lbl.gov/heatisland/ • Resource for heat island / cool roofing research
Sustainable Roofing Resources Renewable Energy & Daylighting • Interstate Renewable Energy Council • http://www.irecusa.org/ • U.S. Department of Energy Solar Energies Technology Program • http://www1.eere.energy.gov/solar/ • Whole Building Design Guide: Building-Integrated Photovoltaics (BIPV) • http://www.wbdg.org/resources/bipv.php • Daylighting Collaborative • http://www.daylighting.org
Sustainable Roofing Resources Vegetated Roofs / Water Management • Penn State Center for Green Roof Research • http://hortweb.cas.psu.edu/research/greenroofcenter • Green Roofs for Healthy Cities • http://www.greenroofs.org • NRCA Green Roof Systems Manual • http://www.nrca.net
Sustainable Roofing Resources Roof Recycling • Construction Waste Management Database • Sponsored by Whole Building Design Guide • National database with state and local sources by material • (http://www.wbdg.org/tools/cwm.php?c=6) • Foam Insulation Recycling • Nationwide Foam (http://www.nationwidefoam.com/) • Single-Ply Roof Recycling • Vinyl Roofing Division, CFFA (http://www.vinylroofs.org/) • EPDM Roofing Association (http://epdmroofs.org) • Metal Roof Recycling • Metal Construction Association (http://www.metalconstruction.org/) • Asphalt Shingle & Wood Shake Recycling • American Roofing Recyclers (http://www.roofingrecyclers.com )
Sustainable Roofing Resources Roof Life Cycle Management WBDG WHOLE BUILDING DESIGN GUIDE • Whole Building Design Guide • Building Commissioning • Facilities Operation & Maintenance • http://www.wbdg.org/index.php • National Roofing Contractors Association Inspection Manuals • Built-Up and Modified Bitumen Roofing Systems • Existing Single-Ply Roofing Systems • Spray Polyurethane Foam-Based Roofing Systems • Steep-Slope & Low-Slope Architectural Metal Panel Roof Assemblies • http://www.nrca.net