ASHRAE 90.1-2010Comparing ASHRAE Standard 90.1 From 2004/2007 to 2010
Course Number: AIACESAER01
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Course Description
The purpose of this presentation is to examine the most recent version of the International Energy Conservation Code and ASHRAE 90.1 Standard, and in particular the parts that most affect architects: building envelope, lighting power reductions, garage design and ventilation. This presentation will contrast the 2010 version with the previous two versions and identify changes to scope, mandatory measures and prescriptive requirements.
Learning Objectives
Identify the new prescriptive envelope changes in the 2010 version vs. 2004-2007 version of ASHRAE 90.1.
Explore the new air barrier requirement and how it affects design and new construction.
Determine updated shading coefficient values and fenestration installation values when applied to the building envelope.
Understand and identify the new reduced lighting power densities and garage ventilation requirements in 90.1.
Applications of the CodeAir BarriersPrescriptive Opaque Envelope ChangesGlass/Low-e CoatingLighting/Power Reductions/Garage VentilationSummary & Questions
Agenda
ASHRAE 90.1 is the reference standard for IECC 2012◦ Supersedes 90.1-2007 by adding over 60 addenda◦ Estimated savings compared to 2007 – 25%◦ Estimated savings compared to 2004 – 30%
ASHRAE 90.1-2010 Review
ASHRAE 90.1 applies to new building portions and systems in new and existing (renovated) buildings.
90.1-2010 now includes new equipment or systems that are identified as part of industrial or manufacturing processes.
All MEP systems are included in 90.1 including:◦ Changes in MEP systems◦ Replacement of MEP system parts◦ Renovation
Scope Changes
D – Daylighting now enabled by glass VT (visible transmittance requirement)
F – Ballasted and vented roofs, including “cool” and vegetative roofs
G – Change Appendix G to normative (mandatory language) will allow Appendix G to be referenced by other standards; e.g., Std. 189.1
H,L,M,N – Improved HVAC Equipment efficiencies
Update of Approved Addenda
Maricopa County IECC 2012
FlagstaffCities which have adopted IECC 2012:• Avondale• Chandler• Glendale• Peoria (Optional)• Phoenix• Scottsdale• Maricopa County
Alternative compliance paths (Section C402.2) Commercial buildings are required to comply with one of the
following:◦ ANSI/ASHRAE/IESNA 90.1-2010
◦ Requirements of C402, C403, C404, and C405 AND commercial buildings Section C406.2, C406.3 OR C406.4
◦ Requirements of C407, C402.4, C403.2, C404, C405.2, C405.3, C405.4, C405.6, C405.7
IECC 2012 Compliance Paths
Additional Efficiency Package Options
◦ C406.2 – Efficient HVAC Performance
◦ C406.3 – Efficient Lighting Systems
◦ C406.4 – On-Site Supply of Renewable Energy
IECC 2012 Requirements
Applications of the Code
Air BarriersPrescriptive Opaque Envelope ChangesGlass/Low-e CoatingLighting/Power Reductions/Garage VentilationSummary & Questions
Agenda
IECC 2012◦ Not required in buildings located in Climate Zones 1, 2, or 3
ASHRAE 90.1-2010◦ Air barrier construction required in all climate zones. ◦ Exception – Semi-Heated spaces in climate zones 1-6.◦ Exception – Single Wythe Concrete Masonry Buildings in CZ
2B
Air Barrier Design
AZ Climate Zones
Phoenix
Tucson
Flagstaff
Mandatory Provisions (Section 5.4)◦ Continuous air barrier on entire building envelope
◦ Secure building wrap with sealed or gasketed joints
◦ Using individual materials that have an air permeability of ≤ 0.004 cfm/ft2
OR◦ Using assemblies of materials and components that
have an average air leakage of ≤ 0.04 cfm/ft2, curtainwall assemblies ≤ 0.03 cfm/ft2
◦ Door Construction ≤ 0.4 cfm/ft2
Air Barrier Design - ASHRAE 90.1
Mandatory Provisions (Section C402.4)◦ Continuous air barrier on entire building envelope
◦ Secure building wrap with sealed or gasketed joints
◦ Using individual materials that have an air permeability of ≤ 0.004 cfm/ft2
OR◦ Using assemblies of materials and components that
have an average air leakage of ≤ 0.04 cfm/ft2, curtainwall assemblies ≤ 0.03 cfm/ft2
◦ Building Testing ≤ 0.4 cfm/ft2 @ 0.3” W.G.
Air Barrier Design – IECC 2012
Section 5.4.3.1.1◦ The air barrier shall be designed and noted in the following manner:
All air barrier components of each building envelope assembly shall be clearly identified or otherwise noted on the construction documents.
The joints, interconnections and penetration of the air barrier components including lighting fixtures shall be detailed unless otherwise noted.
The continuous air barrier shall extend over all surfaces of the building envelope (at the lowest floor, exterior walls, and ceiling or roof).
The continuous air barrier shall be designed to resist positive and negative pressures from wind, stack effect, and mechanical ventilation.
Air Barrier Design
To minimize reheat energy, a limit has been set on the supply air temperature of reheated air to 20°F above the space temperature setpoint.
Intended to minimize short-circuiting of reheated air into the return or exhaust system before it can be effective in heating or ventilating the space.
Air Barrier & HVAC Design
Sealed, caulked, gasketed or weather-stripped:◦ Joints around windows and doors◦ Fenestration joints between walls/foundation and walls/roof◦ Envelope penetrations◦ Penetrations through vapor retarders◦ Site built fenestration and doors◦ All other openings in building envelope
Exceptions:◦ Semiheated spaces
Air Barrier Installation
Conditioned Space◦ Cooled by a cooling system with a sensible output capacity > 5 Btu/h-ft2
◦ Heated by a heating system with an output capacity > 15 Btu/h-ft2 for Zone 4◦ Indirectly conditioned space that is adjacent to conditioned space but neither
heated or cooled. Semiheated Space
◦ Heated at > 3.4 Btu/h-ft2, but not classified as conditioned Unconditioned Space
◦ Crawl Spaces, Attics, etc.
Space Type Definitions
Space Definitions
Graphics Credit: PNNL
Required for all building entrances > than 1000 ft2. Vestibules must have:
◦ Self closing doors◦ Interior and exterior doors not necessary to open
both at the same time◦ Distance between interior and exterior
doors not < 7ft when in closed position
Exceptions:◦ Buildings in CZ’s 1,2◦ Revolving Doors◦ Dwelling Units◦ “Non-entrance” doors
entering a space < 3,000 ft2.
Air Leakage – ASHRAE 90.1
Graphics Credit: PNNL
Graphics Credit: PNNL
Applications of the CodeAir Barriers
Prescriptive Opaque Envelope ChangesGlass/Low-e CoatingLighting/Power Reductions/Garage VentilationSummary & Questions
Agenda
Building Envelope Compliance
Mandatory Provisions
(required for most compliance options)
Building System Compliance Options
Energy Code Compliance
Prescriptive Option
Energy Cost Budget
Trade Off Option
Simplified
Envelope
HVAC
Lighting
SWH
Power
OtherGraphics Credit: PNNL
8 criteria sets for different climate types◦ Each set is a single page that summarizes requirements based on
climate zone Insulation levels for roofs, walls and floors Fenestration Criteria
More stringent than the 50% allowance in 90.1-2004 Alternative is to use the Trade-Off Option (Section 5.6)
Building Envelope – Prescriptive Option
Window Wall Ratio (WWR) ≤ 40% of gross wall area
Skylight-Roof Ratio ≤ 5% of roof area
Each envelope component must separately meet requirements of Table 5.5
◦ Fenestration U-factor requirements in 90.1-2007 are around 38% lower than those in 2004
◦ Fenestration SHGCs are about equal in nonresidential buildings
◦ SHGCs apply to all exposures and are no longer exempt in the north orientation as they were in 2004
◦ The north wall has a reduction of about 59% as compared to 2004
◦ Roofs with attics and roofs with above deck insulation have U-factor requirements are 20% to 24% lower.
◦ Wall U-factor requirements remain about the same.
Changes in the Standard - Envelope
Opaque ElementsTABLE 5.5-2 Building Envelope Requirements For Climate Zone 2 (A, B)*
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
RoofsInsulation Entirely above Deck
Metal BuildingAttic and Other
U-0.063U-0.065U-0.034
R-15.0 c.i.R-19.0R-30.0
U-0.063U-0.065U-0.027
R-15.0 c.i.R-19.0R-38.0
U-0.218U-0.167U-0.081
R-3.8 c.i.R-6.0R-13.0
2004
Opaque ElementsTABLE 5.5-4 Building Envelope Requirements For Climate Zone 2 (A, B)*
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
RoofsInsulation Entirely above Deck
Metal BuildingAttic and Other
U-0.048U-0.065U-0.027
R-20.0 c.i.R-19.0R-38.0
U-0.048U-0.065U-0.027
R-20.0 c.i.R-19.0R-38.0
U-0.218U-0.167U-0.081
R-3.8 c.i.R-6.0R-13.0
2007
Opaque Elements
Reference Table 5.5-4 on page 29 in 90.1-2010
TABLE 5.5-2 Building Envelope Requirements For Climate Zone 2 (A, B)*
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
RoofsInsulation Entirely above Deck
Metal BuildingAttic and Other
U-0.048U-0.055U-0.027
R-20.0 c.i.(2) R-13.0R-38.0
U-0.048U-0.055U-0.027
R-20.0 c.i.(2) R-13.0R-38.0
U-0.218U-0.097U-0.081
R-3.8 c.i.R-10.0R-13.0
2010
Opaque Elements
Reference Table C402.1.2 and C402.2
TABLE C402.1.2 / C402.2 Thermal Envelope Assembly Requirements For Climate Zone 2*
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
RoofsInsulation Entirely above Deck
Metal BuildingAttic and Other
U-0.048U-0.035U-0.027
R-20.0 c.i.R-19+R-11LSR-38.0
U-0.048U-0.035U-0.027
R-20.0 c.i.R-19+R-11LSR-38.0
IECC 2012
Opaque ElementsTABLE 5.5-2 Building Envelope Requirements For Climate Zone 2 (A, B)*
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
Walls, Above GradeMass
Mass BuildingSteel-Framed
Wood-Framed and Other
U-0.580U-0.113U-0.124U-0.089
NRR-13.0R-13.0R-13.0
U-0.151U-0.113U-0.124U-0.089
R-5.7 c.i.R-13.0R-13.0R-13.0
U-0.580U-0.184U-0.352U-0.292
NRR-6.0NRNR
2004
Opaque ElementsTABLE 5.5-2 Building Envelope Requirements For Climate Zone 2 (A, B)*
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
Walls, Above GradeMass
Mass BuildingSteel-Framed
Wood-Framed and Other
U-0.151U-0.113U-0.124U-0.089
R-5.7 c.i.R-13.0R-13.0R-13.0
U-0.123U-0.113U-0.064U-0.089
R-7.6 c.i.R-13.0R-13.0+R-7.5c.i.R-13.0
U-0.580U-0.184U-0.124U-0.089
NRR-6.0R-13.0R-13.0
2007
Opaque Elements
Reference Table 5.5-2 on page 27 in 90.1-2010
TABLE 5.5-2 Building Envelope Requirements For Climate Zone 2 (A, B)*
2010
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
Walls, Above GradeMass
Mass BuildingSteel-Framed
Wood-Framed and Other
U-0.151U-0.093U-0.124U-0.089
R-5.7 c.i.R-16.0R-13.0R-13.0
U-0.123U-0.093U-0.064U-0.089
R-7.6 c.i.R-16.0R-13.0+R-7.5c.i.R-13.0
U-0.580U-0.113U-0.124U-0.089
NRR-13.0R-13.0R-13.0
Opaque Elements
Reference Table C402.1.2 and C402.2
TABLE C402.2 Building Envelope Requirements For Climate Zone 2*
2012 IECC
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
Walls, Above GradeMass
Mass BuildingSteel-Framed
Wood-Framed and Other
U-0.142U-0.079U-0.077U-0.064
R-5.7 c.i.R-13.0+R-6.5c.i.R-13.0+R-5.0c.i.R-20 OR R-13.0+R-3.8c.i.
U-0.123U-0.079U-0.064U-0.064
R-7.6 c.i.R-13.0+R-13.0c.i.R-13.0+R-7.5c.i.R-20 OR R-13.0+R-3.8c.i.
Opaque ElementsTABLE 5.5-2 Building Envelope Requirements For Climate Zone 2 (A, B)*
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
Walls, Below GradeBelow Grade Wall C-1.140 NR C-1.140 NR C-1.140 NR
2004
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
FloorsMass
Steel JoistWood-Framed and Other
U-0.107U-0.052U-0.051
R-6.3 c.i.R-19.0R-19.0
U-0.087U-0.052U-0.033
R-8.3 c.i.R-19.0R-30.0
U-0.322U-0.069U-0.282
NRR-13.0NR
Opaque ElementsTABLE 5.5-4 Building Envelope Requirements For Climate Zone 4 (A, B, C)*
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
Walls, Below GradeBelow Grade Wall C-1.140 NR C-1.140 NR C-1.140 NR
2007
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
FloorsMass
Steel JoistWood-Framed and Other
U-0.107U-0.052U-0.051
R-6.3 c.i.R-19.0R-19.0
U-0.087U-0.052U-0.033
R-8.3 c.i.R-19.0R-30.0
U-0.322U-0.069U-0.066
NRR-13.0R-13.0
Opaque Elements
Reference Table 5.5-2 on page 27 in 90.1-2010
TABLE 5.5-4 Building Envelope Requirements For Climate Zone 4 (A, B, C)*
2010
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
Walls, Below GradeBelow Grade Wall C-1.140 NR C-1.140 NR C-1.140 NR
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
FloorsMass
Steel JoistWood-Framed and Other
U-0.107U-0.052U-0.051
R-6.3 c.i.R-19.0R-19.0
U-0.087U-0.052U-0.033
R-8.3 c.i.R-19.0R-30.0
U-0.322U-0.069U-0.066
NRR-13.0R-13.0
Opaque Elements
Reference Table C402.1.2 and C402.2
TABLE C402.1.2 Building Envelope Requirements For Climate Zone 2*
2012 IECC
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
Walls, Below GradeBelow Grade Wall C-1.140 NR C-1.140 NR C-1.140 NR
Opaque ElementsNonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
FloorsMass
Joist/FramingU-0.107U-0.033
R-6.3 c.i.R-30.0
U-0.087U-0.033
R-8.3 c.i.R-30.0
Applications of the CodeAir BarriersPrescriptive Opaque Envelope Changes
Glass/Low-e CoatingLighting/Power Reductions/Garage VentilationSummary & Questions
Agenda
Fenestration OrientationVertical fenestration area to meet this requirement:
Area South ≥ Area West and Area South ≥ Area East
Exceptions:• Buildings shaded by other buildings within 20 ft to the south which is at least
½ as tall as the proposed building (structures only – no trees)• Buildings with shade on 75% of the west and east• Alterations and additions that don’t increase vertical fenestration area
N
No! Yes!Graphics Credit: PNNL
Window Orientation – No Daylight Controls
Window Orientation – Daylight Controls
Fenestration
Reference Table 5.5-2 on page 27 in 90.1-2010
TABLE 5.5-4 Building Envelope Requirements For Climate Zone 2 (A, B)*
2004Fenestration
Nonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
Vertical Glazing, % of Wall0-10
10.1-2020.1-3030.1-4040.1-50
U-1.22-1.27U-1.22-1.27U-1.22-1.27U-1.22-1.27U-1.22-1.27
SHGC-0.25-0.61SHGC-0.25-0.61SHGC-0.25-0.61SHGC-0.25-0.61SHGC-0.17-0.44
U-1.22-1.27U-1.22-1.27U-1.22-1.27U-1.22-1.27U-1.22-1.27
SHGC-0.25-0.61SHGC-0.25-0.61SHGC-0.25-0.61SHGC-0.25-0.61SHGC-0.17-0.44
U-1.22-1.27U-1.22-1.27U-1.22-1.27U-1.22-1.27U-0.98-1.02
NRNRNRNRNR
2007/2010Fenestration
Nonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
Vertical Glazing, 0-40% of WallNonmetal Framing (all)
Metal Framing (curtainwall)Metal Framing (entrance doors)
Metal Framing (all other)
U-0.75U-0.70U-1.10U-0.75
SHGC-0.25SHGC-0.25SHGC-0.25SHGC-0.25
U-0.75U-0.70U-1.10U-0.75
SHGC-0.25SHGC-0.25SHGC-0.25SHGC-0.25
U-1.20U-1.20U-1.20U-1.20
NRNRNRNR
Fenestration
Reference Table C402.3
TABLE 5.5-4 Building Envelope Requirements For Climate Zone 2(A, B)*
2012 IECC
Fenestration
Nonresidential Residential Semiheated
AssemblyMaximum
InsulationMin. R-Value
AssemblyMaximum
Insulation Min. R-Value
AssemblyMaximum
InsulationMin. R-Value
Vertical Glazing, 0-40% of WallFixed Fenestration
Operable FenestrationEntrance Doors
U-0.50U-0.65U-0.83
SHGC-0.25SHGC-0.25SHGC-0.25
U-0.50U-0.65U-0.83
SHGC-0.25SHGC-0.25SHGC-0.25
Applications of the CodeAir BarriersPrescriptive Opaque Envelope ChangesGlass/Low-e Coating
Lighting/Power Reductions/Garage VentilationSummary & Questions
Agenda
Lighting Power Density Changes ASHRAE Addendum “by” reduces the LPD requirements
Average LPDs:◦ 2004 – 1.12◦ 2007 – 1.09 (3% Reduction)◦ 2010 – 0.906 (17% Reduction)◦ 2013 - ????
Common Building Types
Building Type 2004 2007 2010
School 1.2 1.2 0.99
Hospital 1.2 1.2 1.21
Office 1.0 1.0 0.9
Convention Center 1.2 1.2 1.08
Sports Arena 1.1 1.1 0.78
Retail 1.5 1.5 1.4
Lighting Power Allowance Changes
2012 IECC Interior Lighting Power Allowances – Building Area Method
Lighting Power Allowances
Building Area Type 2009 2012
Fire Station N/A 0.8
Office 1.0 0.9
Retail 1.5 1.4
Warehouse 0.8 0.6
Lighting Power Allowance Changes
ASHRAE 2007 Addendum “by” reduces additional allowance for lighting specifically designed and directed to highlight merchandise.
Change based primarily oneffective use of CeramicMetal Halide technology
Merchandise Reductions
Merchandise Type 2007 2010
All other products 1.0 0.6
Vehicles, Sporting Goods, Electronics
1.7 0.6
Furniture, Clothing, Cosmetics, Artwork
1.4 1.4
Jewelry, Crystal, China 4.2 2.5
Lighting Power Controls Changes
2012 IECC Interior Lighting Control Requirements
Lighting Control Changes
2009 2012
Light Reduction Controls Automatic Time Switch Control Devices
Automatic Lighting Shutoff Occupancy Sensors
Daylight Zone Control Daylight Zone Control
Occupancy Sensor Control (ASHRAE)
9.4.1 Must function as “manual-on” or “50% auto-on” Occupancy Sensors Required:
◦ Conference Rooms◦ Meeting Rooms◦ Classrooms & Lecture Halls◦ Lunch/Break Rooms◦ Office Spaces > 250ft2
◦ Restrooms◦ Locker Rooms◦ Fitting Rooms◦ Copy/Print Rooms
Occupancy Sensor Control (IECC)
Required in classrooms, conference/meeting rooms, employee lunch/break rooms, private offices, restrooms/storage rooms/janitorial closets and other spaces 300 sq ft or more
Automatic off 30 min of vacancy
100% automatic on allowedin public areas
Must provide a system to automatically detect contaminant levels and adjust fan speed accordingly.
Must be able to reduce fan speed to 50% or less of design capacity.
Garage Ventilation
Garages < 30,000 ft2 with ventilation systems that do not utilize mechanical heating or cooling.
Garages that have an area-to-horsepower ratio that is >1,500 ft2/hp and do not utilize mechanical heating or cooling.
Where not permitted by the AHJ.
Garage Ventilation Exceptions
Applications of the CodeAir BarriersPrescriptive Opaque Envelope ChangesGlass/Low-e CoatingLighting/Power Reductions/Garage Ventilation
Summary & Questions
Agenda
Summary Many prescriptive changes from 2004 2007 2010
Must provide a continuous air barrier
Stricter fenestration and orientations requirements
New garage ventilation requirements
Lighting Power Densities ▼, Control ▲
Questions?
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