Building Energy Efficiency Standards Mandatory measures minimum features that all buildings must have regardless of compliance method used.

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1 Building Energy Efficiency Standards Mandatory measures minimum features that all buildings must have regardless of compliance method used. Note: Cool Roofs is not mandatory in California. Two compliance methods 1. Prescriptive approach menu of minimum features for the entire building (roof/ceilings, walls, floors, HVAC) that sets the minimum threshold for efficiency in each climate zone. No tradeoffs. 2. Performance approach analytical method to determine annual energy performance based on design features of the proposed building. Tradeoff allowed. 1

2 California Climate Zone Map 16 climate zones in California 2

3 Building Energy Efficiency Standards Metric for energy use is time dependent valuation (TDV) The total annual energy use that cannot be exceeded by the building Measures must be cost effective TDV encompasses societal value of energy use» Includes the cost of generation, transmission & distribution of energy» Cost by fuel type for each hour in each climate zone» Carbon costs from energy generation & use 3

4 TDV (electricity) High-value energy (mid-day through afternoon TDV: a kwh saved during high-cost peak hour is valued more highly than a kwh saved during off-peak hour Energy value With flat energy value a kwh saved is valued the same for every hour of the day Monday Flat energy value TDV energy value Friday Source: California Energy Commission

5 Building Energy Use Mandatory Measures Water Heating: type & efficiency, piping, distribution system TDV ENERGY USE Lighting: type, daylighting, controls Envelope: R-values/Ufactors, windows, radiant barrier, cool roof HVAC: type & efficiency, location, distribution system 5

6 Mandatory only If it is considered a Cool Roof Roofing surfaces having reflective properties listed in the CRRC s Rated Product Directory 6

7 Cool Roofs 2013 Liquid Applied Roof Coatings Be Considered A Cool Roof Shall be applied across the entire roof surface to meet the dry mil thickness or coverage recommended by the coating manufacturer, taking in to consideration the substrate on which the coating is applied. Meet the minimum performance requirements listed in the table on the next page or the minimum performance requirements of ASTM C836, D3468, D6083, D6694, whichever are appropriate to the coating material.

8 Cool Roofs 2013 Minimum Performance Requirements For Liquid Applied Roof Coatings For Low-Sloped Roofs Physical Property ASTM Test Procedure Requirement Initial percent elongation (break) D 2370 Minimum 200% 73 ºF (23 ºC) Initial percent elongation (break) OR Initial Flexibility D 2370 D522, Test B Minimum 60% 0ºF (-18 ºC) Minimum pass 1 mandrel 0ºF (-18 ºC) Initial tensile strength (maximum stress) D 2370 Minimum 100 psi (1.38 Mpa) 73ºF (23 ºC) Initial tensile strength (maximum stress) OR Initial Flexibility Final percent elongation (break) after accelerated weathering 1000 h Final percent elongation (break) after accelerated weathering 1000 h OR Flexibility after accelerated weathering 1000h D 2370 D522, Test B D 2370 D2370 Minimum 200 psi (2.76 Mpa) 0ºF (-18 ºC) Minimum pass 1 mandrel 0ºF (-18 ºC) Minimum 100% 73ºF (23 ºC) Minimum 40% 0ºF (-18 ºC) Minimum pass 1 mandrel 0ºF (-18 ºC) Permeance D 1653 Maximum 50 perms Accelerated weathering 1000 h D 4798 No cracking or checking 1 1 Any cracking or checking visible to the eye fails the test procedure.

9 Cool Roofs 2013 (EXCEPTION) Minimum Performance Requirements For Liquid Applied Roof Aluminum-pigmented asphalt roof coatings shall meet the requirements of ASTM D2824 or ASTM D6848 and be installed as specified by ASTM D Cement-based roof coatings shall contain a minimum of 20% cement and shall meet the requirements of ASTM C1583, ASTM D822 and ASTM D5870.

10 Calculated Aged Solar Reflectance (if the Weathered info. not Available) Aged (3 year) solar reflectance required If not measured: R AGED = [0.2 + β[r initial - 0.2] Where: R initial = initial solar reflectance from CRRC directory Product Type CRRC Product Category β Field-Applied Coating Field-Applied Coating 0.65 Other All But Field-Applied Coating

11 Cool Roof Requirements 2013 PRESCRIPTIVE REQUIREMENTS Newly Constructed Building Residential New Construction Climate Zones Aged Solar Reflectance/ Thermal Emittance SRI Steep-sloped / Low-sloped 13 & /

12 Cool Roof Requirements 2013 PRESCRIPTIVE REQUIREMENTS Reroof Residential New Construction Climate Zones Aged Solar Reflectance/ Thermal Emittance SRI Steep-sloped / Low-sloped 13 & / Exception to the residential alterations are provided on the next 2 slides 12

13 2013 PRESCRIPTIVE EXCEPTIONS RESIDENTIAL COOL ROOFS Steep-Sloped (Reroofs Only) 1. Air-space of 1.0 inch is provided between the top of the roof deck and the bottom of the roofing product; Or 2. Installed roofing product has a profile ratio of rise to width of 1 to 5 for 50% or greater of the width of the roofing product; Or 3. Ducts sealed and tested to altered existing duct requirements; Or 4. R-38 Ceiling Insulation; Or 5. Radiant barrier; Or 6. No Ducts in Attic; Or 7. Climate Zones 10-15, R-4 or greater insulation above roof deck. 13

14 2013 PRESCRIPTIVE EXCEPTIONS RESIDENTIAL COOL ROOFS Low-Sloped (Reroofs) 1. No Ducts in Attic; Or 2. Aged solar reflectance can be traded for insulation at the roof deck. Low-sloped insulation tradeoffs Aged Solar Reflectance Roof Deck Insulation R-value Aged Solar Reflectance Roof Deck Insulation R-value

15 2013 PRESCRIPTIVE REQUIREMENTS Newly Constructed Building Nonresidential New Construction Climate Zones Aged Solar Reflectance/ Thermal Emittance SRI Steep-sloped / Low-sloped / Exception to the Nonresidential new construction low-sloped roofs are provided on the next slide 15

16 2013 PRESCRIPTIVE EXCEPTIONS Nonresidential Cool Roofs Low-Sloped (Newly Constructed Building) 1. Wood framed roofs in CZ 3 and 5 are exempt from the minimum requirements for solar reflectance and thermal emittance or SRI if the roof assembly has a U-factor of or lower. 2. Metal framed roofs in CZ 3 and 5 are exempt from the minimum requirements for solar reflectance and thermal emittance or SRI if the roof assembly has a U-factor of or lower. 3. Aged solar reflectance less than 0.63 is allowed provided the maximum roof/ceiling U-factor is no exceeded. Aged Solar Reflectance Metal Building Climate Zones 1-16 U-factor Wood Framed and Other Climate Zones 1 & 5 U-factor Wood Framed and Other Climate Zones 2-4, 9-16 U-factor Wood Framed and Other Climate Zone 6 U-factor Wood Framed and Other Climate Zones 7 & 8 U-factor

17 Cool Roof Requirements 2013 PRESCRIPTIVE REQUIREMENTS Newly Constructed Building High-Rise Residential & Hotel & Motels New Construction Climate Zones Aged Solar Reflectance/ Thermal Emittance SRI Steep-sloped / Low-sloped 9, 10, 11, 13, 14 & /

18 NONRESIDENTIAL AND HOTEL/MOTEL OCCUPANCIES ADDITIONS, ALTERATIONS, AND REPAIRS If >50% or >2,000 ft 2 of roof area, whichever is less, is being replaced, recovered, or recoated, prescriptive cool roof requirements kick in [Can use Performance Approach to avoid Cool Roof but ONLY if other highly efficient energy features are being changed at the same time allowing for trade-offs]

19 Cool Roof Requirements 2013 PRESCRIPTIVE REQUIREMENTS Reroofs Nonresidential New Construction Climate Zones Aged Solar Reflectance/ Thermal Emittance SRI Steep-sloped / Low-sloped / Exception to the Nonresidential new construction low-sloped roofs are provided on the next slide 19

20 2013 PRESCRIPTIVE EXCEPTIONS NONRESIDENTIAL COOL ROOFS Low-Sloped (reroofs) Aged solar reflectance can be traded for insulation at the roof deck. Low-sloped insulation tradeoffs Aged Solar Reflectance Climate Zone 1, 3-9 U-factor Climate Zone 2, U-factor

21 2013 PRESCRIPTIVE EXCEPTIONS High-Rise Residential Hotels & Motels Reroofs Climate Zones Aged Solar Reflectance/ Thermal Emittance SRI Low-Sloped 9, 10, 11, 13, 14 & /0.75 SRI = 64 Steep -Sloped /0.75 SRI = 16

22 ALTERATIONS AND REPAIRS Nonresidential, High-Rise Residential, Hotel/Motel When the roof deck or the recover boards are exposed in nonresidential, high-rise residential and hotel/motel, it shall be insulated to the levels on the next slide

23 Insulation Requirements for Alterations Climate Zone Nonresidential Continuous Insulation R-value Roof U-factor High-rise Residential and Guest Rooms of Hotel/Motel Buildings Continuous Insulation R-value U-factor 1 R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R

24 Exceptions To The Requirements of the Table 1. The existing roof is insulated with at least R-7 insulation or it has a U-factor lower than If mechanical equipment is located on the roof and it will not be disconnected and lifted as part of the roof replacement, insulation added may be limited to the maximum insulation thickness that will allow a height of 8 inches (203 mm) from the roof membrane surface to the top of the base flashing. 3. If adding the required insulation will reduce the base flashing height to less than 8 inches (203 mm) at penthouse or parapet walls, the insulation added may be limited to the maximum insulation thickness that will allow a height of 8 inches (203 mm) from the roof membrane surface to the top of the base flashing, provided that the conditions in subsections i through iv apply:

25 Exception to 3 of the previous slide i. The penthouse or parapet walls are finished with an exterior cladding material other than the roofing covering membrane material; and ii. iii. iv. The penthouse or parapet walls have exterior cladding material that must be removed to install the new roof covering membrane to maintain a base flashing height of 8 inches (203 mm); and For nonresidential buildings, the ratio of the replaced roof area to the linear dimension of affected penthouse or parapet walls shall be less than 25 square feet per linear foot for climate zones 2 and 10 through 16, and less than 100 square feet per linear foot for climate zones 1 and 3 though 9; and For high-rise residential buildings, hotels or motels, the ratio of the replaced roof area to the linear dimension of affected penthouse or parapet walls shall be less than 25 square feet per linear foot for all climate zones

26 Exception 4 To The Insulation Table Tapered insulation may be used which has a thermal resistance less than that prescribed in Table 149-A at the drains other low points, provided that the thickness of insulation is increased at the high points of the thickness of insulation is increased at the high points of the roof so that the average thermal resistance equals or exceeds the value that is specified in Table 149-A.

27 Frequently Asked Questions What about Integrated Photovoltaic panels and building integrated solar thermal panels? If the panel is on a rack system then cool roof is required. But if the PV system is integrated as part of the roof then cool roof is not required for that area. What about ballasted roofs? Is considered a cool roof if the unit weight is at least 25 lb/ft 2 What about green roofs? Is considered a cool roof if the unit weight is at least 25 lb/ft 2

28 Thank You Questions? 28