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2011 Vermont Commercial Building Energy Standards (CBES)
February 9, 2012Efficiency Vermont—Better Buildings By Design
2
Efficiency Vermont is a Registered Provider with The American Institute of Architects Continuing Education Systems (AIA/CES). Credit(s) earned on completion of this program will be reported to AIA/CES for AIA members. Certificates of Completion for both AIA members and non-AIA members are available upon request.
This program is registered with AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product.
Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.
3
Learning Objectives Understand basic background and history of Vermont’s energy
code.
Understand the basic requirements for meeting Vermont’s 2011
RBES and CBES.
Understand differences between applicability of RBES vs.
CBES in specific project scenarios.
Learn what methods can be used to show compliance with
RBES and CBES.
4
Course EvaluationsIn order to maintain high-quality learning experiences, please
access the evaluation for this course by logging into CES Discovery and clicking on the Course Evaluation link on the
left side of the page.
5
Overview
•CBES Update Process
•Administration
•General Requirements
•Envelope
•Mechanical Systems
•Service Water Heating
•Electrical Power and Lighting
6
CBES Update Process
•Vermont must meet minimum 2009 IECC/ASHRAE 90.1-2007 (ARRA requirements)
•Carry-over and add VT-specific amendments and improvements
•Consider changes included in 2012 IECC/ASHRAE 90.1-2010
7
CBES Update Process
2011 VT CBES
2007/2010 ASHRAE
90.1
2005 VT CBES
2009/2012 IECC
8
CBES Update Process
• The update process was not focused on enforcement/compliance
• Acceptance of ARRA funds requires the state to develop a plan to improve and evaluate compliance
• State is currently developing this plan and working with stakeholders
9
VERMONTCOMMERCIAL BUILDING
ENERGY STANDARDS (CBES)
10
CHAPTER 1:ADMINISTRATION
11
All buildings covered EXCEPT:
• R-3 buildings (single detached houses and duplexes)
• R-2 and R-4 buildings 3 or less stories in height (apartments, dorms, assisted living, residential care)
12
Scope and Exempt Buildings
101.2 Scope
• The code does not apply to farm structures or process applications (“equipment or portions of building energy systems that use energy primarily to provide for industrial, manufacturing or commercial processes”)
101.5 Compliance
Exempt Buildings:
1. Low energy buildings (<3.4 Btu/h*ft2 for space conditioning)
2. Unconditioned buildings
3. Inflatable buildings
13
101.4.3 Additions, Alterations, Renovations and Repairs
Working on an existing building?
If you touch it, bring it up to code…
Additions, alterations, renovations or repairs to an existing building, building system or portion thereof shall conform to the provisions of this code…
without requiring the unaltered portion(s) of the existing building or building system to comply with this code.
With some exceptions…
14
101.4.3 Additions, Alterations, Renovations and Repairs
Exceptions:
• Storm windows installed over existing fenestration.
• Glass only replacements in an existing sash and frame.
• Existing ceiling, wall or floor cavities exposed during construction provided that these cavities already are filled with insulation.
• Construction where the existing roof, wall or floor cavity is not exposed.
• If you replace an existing door, separating conditioned space from exterior, you do not need to add a vestibule; however, if a vestibule is part of the door assembly that is modified, it must remain on the building or be replaced [paraphrased]
15
101.4.3 Additions, Alterations, Renovations and Repairs
New Exceptions:
• Re-roofing where neither sheathing nor insulation is exposed
• Up to 50% of the luminaires can be replaced as long as the load is not increased in the building
• Bulb & ballast replacements are exempt providing the alteration does not increase the load.
Context: New in 2009 IECC
16
101.4.4 Change in Occupancy or Use• 2005 CBES required a building undergoing a change in
occupancy resulting in increased load to comply with the code
• 2011 CBES
(1) maintains same language (“space” in lieu of “building”)
and
(2) requires installed lighting wattage to comply with CBES if the space changes from one use to another use as defined in Lighting Power Allowance Table
17
101.4.5 Change in Space ConditioningAny non-conditioned space that is altered to become
conditioned space shall be required to be brought into full compliance with thiscode.
18
103.2: Construction Documents
1. Added: Additional information required on construction documents
a. Design ambient temperatures; interior temperatures for heating and cooling modes; relative humidity setpoints; ventilation rates;
2. Added: Additional information required on mechanical equipment schedules
a. Equipment efficiencies; Fan and pump nameplate motor and brake horsepower; Hydronic system (if applicable) supply and return water design temperatures for boilers and all terminal devices (e.g. baseboards, unit ventilators, etc); Steam system (if applicable) design pressure for boilers and all terminal devices
Context: Useful information for code review, commissioning, future energy audits, etc
19
CHAPTER 3:GENERAL REQUIREMENTS
20
301.2: Design Conditions
• 2005 CBES had broad allowance for adjustments.
• 2011 CBES: Allows adjustments for:
1. Winter heating design temperatures for projects either:
a. Located at an elevation of 1,500 feet or higher or
b. Located in Caledonia, Essex or Orleans counties
2. As approved by the code official or other authority having jurisdiction
Context: Improves language from 2005 VT CBES which allowed adjustments for “local design conditions”
21
CHAPTER 5: COMMERCIAL ENERGY EFFICIENCY
22
What are My Options for Complying with the 2011 VT CBES?
1. Chapter 5 - General Prescriptive Approach
•Use for ≤ 40% of gross wall area in vertical fenestration
•Use for ≤ 3% of gross roof area in skylights
2. ASHRAE/IESNA Standard 90.1-2007
• 2005 CBES allowed individual sections to comply with either CBES or ASHRAE 90.1
• 2011 CBES requires compliance with either CBES or ASHRAE 90.1 in its entirety
23
CBES Compliance PathsMust the
Project Comply with the CBES?
Comply with the Envelope
Requirements
Comply with the Mechanical/SWH
Requirements
Comply with the Power & Lighting
Requirements
Section 502 90.1 Section 5 Sections 503 and 504 90.1 Section 6 Section 505 90.1 Section 9
Document Compliance with
the CBES
Post/Submit Certificates
Inspection
24
SECTION 502:BUILDING ENVELOPE
25
Major Changes to Envelope Requirements
• Added Group R category for insulation
• Revised insulation requirements
• Added/revised descriptions metal building walls/roofs
• Consolidated skylight categories into one category
• Expanded air leakage requirements
• Revised vestibule requirements
26
Building Envelope502.2.1:Roof Assembly
Skylight and mechanical curbs required to insulate skylight to at least R-5
27
Building EnvelopeTable 502.2 (1) Envelope Tables
1. Envelope R-Values/U-Factors are only for Vermont Climate Zone 6
2. Added additional metal building description and U-factor reference tables
3. Maximum Vertical fenestration area is 40% of above-grade wall area, same as 2009 IECC. 2005 CBES was 50% maximum.
28
Building Envelope: RoofsRoofs 2005
VT CBES2009 IECC/90.1-2007
2011 CBES
Roof: Insulation entirely
above deck
R-24ci
U - 0.040
R-20ci
U-0.048
R-30ci
U - 0.032
Metal Buildings
R-19+R-10 or R-30
U-0.051
R-13+R-19
U-0.049
*See Options*
U-0.049
Steel Joist
R-30+R-5ci (with R-5 thermal
blocks)U-0.027
N/A N/A
Attic and other
R-38U-0.027
R-38U-0.027
R-38U-0.027
29
Building Envelope: Metal Building RoofsLiner System (Ls):
A continuous membrane installed below the purlins and uninterrupted by framing members. Uncompressed, un-faced insulation rests on top of the membrane between the purlins.
For multilayer installations, the last rated R-value of insulation is for unfaced insulation draped over purlins and then compressed when the metal roof panels are attached. A minimum R- 3 thermal spacer block between the purlins and the metal roof panels is required, unless compliance is shown by the overall assembly U-factor.
Example: R-19 + R-11 Ls U-0.035
30
Building Envelope: Above-Grade Walls
30
Walls-Above Grade
2005 VT CBES
2009 IECC/90.1-2007
2011 VT CBES
Mass
R-9.5ci
U-0.104
R-13.3ci
U-0.080
R-13.3ci
U-0.080
[GROUP R]R-15.2ciU-0.071
Metal building
R-19 or R-6+R-13
U-0.070
R-13 + R-5.6ci
U - 0.069
R-11 + R-13ci orR-19.5ci
U-0.054
Metal-framed
R-13+R-7.5ci
U-0.064
R-13+R-7.5ci
U-0.064
R-13+R-7.5ci orR-13ci
U-0.064
Wood-framed and other
R-19 or R-12ci or
R-13+R-3.8ci
U-0.064
R-13+R-7.5ci
U-0.051
R-13+R-7.5ci orR-20 + R-3.8ci or
R-23 or R-15ci
U-0.051
31
Building Envelope: Below-Grade Walls
Note: VT was already ahead of 2009 IECC. Maintained the current 2005 VT CBES values.
Walls-Below Grade 2005 VT CBES
2009 IECC/90.1-2007
2011 VT CBES
Below Grade Wall
R-10ci
C-0.092
R-7.5ci
C-0.119
R-10ci
C-0.092
32
Building Envelope: Floors
Floors 2005 VT CBES
2009 IECC/90.1-2007
2011 VT CBES
Mass
R-10ci
U-0.074
R-12.5ci
U-0.064
R-12.5ci
U-0.064
Joist/Framing-Metal
R-30
U-0.038
R-30[Group R] R-
38
U-0.033
R-30
U-0.038
[Group-R]
R-38U-0.032
Joist/Framing-Wood and
Other
R-30
U-0.033
R-30
U-0.033
R-30
U-0.033
33
Building Envelope: Slab-on-GradeSlab-on-Grade Floors*
2005 VT CBES
2009 IECC/90.1-2007
2011 VT CBES
Unheated
R-10 for 48 inches
F-0.64
R-10 for 24 inches below
F-0.55
R-10 for 48 inches
F-0.48**
Heated
R-10 for entire slab (under
slab and perimeter)
F-0.55
R-15 for 24 inches below
F-0.86
R-10 for entire slab (under slab and perimeter)
F-0.55*The insulation shall be placed on the exterior of the foundation
**Change to F-Value from 2005 CBES to reflect vertical installation
34
Building Envelope: Opaque Doors
Opaque Doors
2005 VT CBES
2009 IECC/90.1-2007
2011 CBES Proposed Values
Swinging U-0.50 U-0.70 U-0.37
Roll-Up or sliding R-10 U-0.50 U-0.20 (R-5)
Upward-Acting or Sectional N/A N/A R-10
• IECC /90.1 only provides U-Factors• Upward-Acting or Sectional is new and unique to the Vermont code. Note typo in draft posted on web
35
Building Envelope: Fenestration Category 2005 VT CBES 2009 IECC 2011 VT CBES
Vertical Fenestration (Maximum %) 50% 40% 40%
Framing Materials other than Metal with or without Metal Reinforcement or Cladding U‐0.35 U‐0.35 U‐0.35
Metal framing with or without Thermal BreakCurtain Wall/Storefront U‐0.45 U‐0.45 U‐0.42
Entrance Door U‐0.80 U‐0.80 U‐0.80All Other U‐0.50 U‐0.55 U‐0.50
SHGC‐All Frame TypesPF < 0.25 0.40 0.40 0.40
0.25 < PF < 0.5 0.55 NR 0.55PF >= 0.5 NR NR NR
Skylights (Maximum %) 5% 3% 3%Skylights, Glass U‐0.60 U‐0.60 U‐0.50
SHGC‐0.40 SHGC‐0.40 SHGC‐0.40Skylights, Plastic U‐0.60 Plastic Not Specified
SHGC‐0.62 Plastic Not Specified
36
Section 502.4. Air Leakage• 2005 CBES/2009 IECC: broad language
• 2011 CBES: Mandatory continuous air barrier
Three air barrier compliance options:
• Option 1: Materials
• Option 2: Assemblies
• Option 3: Building Test (0.50 cfm/ft2 of shell area @ 50 Pa)
Air Barrier penetrations-explicit language on air sealing
Fenestration air leakage table
Context: Included in 2012 IECC. Originally adapted from MA building code, so it is “field-tested” and regionally appropriate.
37
Section 502.4. Air Leakage -Materials
1. 3/8-inch (10 mm) plywood.
2. 3/8-inch (10 mm) oriented strand board (OSB).
3. 1/2-inch (12 mm) extruded polystyrene.
4. 1/2-inch (12 mm) foil-backed polyisocyanurate.
5. 11/2-inch (36 mm) closed-cell spray foam.
6. 41/2-inches (113 mm) open-cell spray foam.
7. 1/2-inch (12 mm) gypsum board.
8. 1/2-inch (112 mm) cement board.
9. Built-up roofing.
10. Modified bitumen roofing.
11. Fully adhered, single-ply roofing.
12. 5/8-inch (16 mm) Portland sand parge or gypsum plaster.
13. Cast-in-place or precast concrete.
14. Fully grouted block masonry.
15. Sheet steel or aluminum.
Fifteen materials deemed to comply if installed properly:
38
Section 502.4. Air Leakage -AssembliesPresumptive compliance if installed
properly:
1. Sealed concrete masonry unit (CMU) (coated with one application of block filler and two applications of a paint or sealer coating) or
2. 1/2-inch (12 mm) Portland cement/sand parge, stucco or plaster or
3. Concrete block masonry with all cores filled with grout
39
Section 502.4. Air Leakage –Building Test
Building’s air leakage rate cannot exceed 0.50 cfm/ft2 at 50 Pa in accordance with ASTM E 779.
40
Section 502.4.7 Vestibules
a. Utilizes new definition of “Building Entrance”
b. If vestibule is tempered, max temperature setting of 55° F. Cooling prohibited.
c. If tempered, shall be constructed according to envelope provisions
d. If tempered, thermostat shall be programmable and inaccessible to public
41
SECTION 503:BUILDING MECHANICAL
SYSTEMS
42
Major Changes to Mechanical Requirements• Revises equipment efficiency tables for water-chilling
packages
• Requires snow melt control
• Requires demand control ventilation (DCV) for certain spaces
• Removes exception for energy recovery ventilation for lab fume hood systems ≤ 15,000 cfm
• Lowers the system capacity for economizer requirement to 54,000 Btu/h
• Introduces fan power limitations
• Reorganizes hydronic water loop heat pump section
• Introduces supply air temperature reset controls for multiple-zone systems
43
Section 503 Building Mechanical Systems
Simplified to Include Only Four Sections:
• What Provisions of the Code Apply (503.1)
• Mandatory Provisions (503.2)
• Simple HVAC Systems and Equipment (503.3)
• Complex HVAC Systems and Equipment (503.4)
44
Simple Versus Complex SystemsBuildings served by unitary or
packaged HVAC each serving 1 zone controlled by 1 thermostat. Two-pipe heating systems serving multiple zones are included if no
cooling system is installed
[Tables 503.2.3(1) through 503.2.3(5)]
Section 503.3Simple Systems
Section 503.4Complex Systems
All buildings served by HVAC systems not
covered under 503.3
45
Simple Versus Complex Systems
46
Section 503.1.2 Electric Resistance Space Heating
Prohibition on electric resistance space heating
• Carried over from 2005 VT CBES
• Exceptions:
• Stairways
• Replacement of existing unit
• Special conditions (health/safety/environmental)
• Limited areas/practical application (e.g., restroom distant from distribution system)
47
The automatic controls for a snow-melt system shall be capable of shutting off the system when the pavement temperature is above _____ and no precipitation is falling.
1. 35°F
2. 45°F
3. 40°F
4. 50°F
Pavement above 50F, but notethat systems shall also include an automatic or manual control that will allow shutoff when the outdoor temperature is above 40°F(4°C) so that the potential for snow or ice accumulation is negligible.
48
Section 503.2.5 Ventilation
• References ASHRAE 62.1-2007 rather than IMC
• Ventilation rates to be based on expected occupancy levels versus default ASHRAE 62.1 rates, where available
o Goal: avoid using worst-case ventilation rates when better information is available
49
Section 503.2.5.2 Demand Controlled Ventilation
• 2005 CBES had no DCV requirement
• 2011 CBES: DCV must be provided for each zone with spaces > 500 ft² and the average occupant load > 40 people/1000 ft² of floor area where the HVAC system has:
• An air-side economizer, or
• Automatic modulating control of the outdoor air damper, or
• A design outdoor airflow > 3,000 cfmDemand controlled ventilation (DCV): a ventilation system capability that provides for the automatic reduction of outdoor air intake below design rates when the actual occupancy of spaces served by the system is less than design occupancy.
50
Section 503.2.5.2 Demand Controlled Ventilation - Exceptions
• Systems with energy recovery per 503.2.6
• Multiple zone systems without direct digital control of single zones communicating with central control panel
• Systems with design outdoor airflow < 1,200 cfm
• Spaces where supply airflow rate minus any makeup or outgoing transfer air requirement < 1,200 cfm
51
Section 503.2.7: Duct and Plenum Insulation and Sealing
*When located within a building envelope assembly, the duct or plenum shall be separated from the building exterior or unconditioned or exempt spaces by a minimum of R-10 insulation.
51
2005 VT CBES 2011 VT CBES
Unconditioned Spaces
R-5 R-8
Exterior R-8 R-10
Within BuildingEnvelope Assembly*
R-8 R-10
Typo online
52
Section 503.2.10: Systems Performance Verification and Completion
1. Buildings ≥ 50,000 SF
2. Requires independent, third-party commissioning agents to perform functional testing to verify efficient “as-designed” operation of three systems:
a. Economizers
b. VAV fan control
c. Part load hydronic controls
3. Prescriptive testing requirements for each of these systems
FAIL
53
Section 503.2.10: Systems Performance Verification and Completion
Qualifications:
1. Have experience as a commissioning authority on at least (3) previous projects each at least 20,000 SF or greater, and
2. Be an independent third party entity. The commissioning authority shall not be an employee of the design team, construction team, owner or developer.
54
Section 503.2.10: Systems Performance Verification and Completion
Example of Requirements:
Test and record the following:
A. Economizers (Section 503.3.1)
A.1. Method of economizer control
A.2. Economizer setpoints
A.3. Economizer operates in full 100% outside air mode when enabled.
A.4 Economizer operates with additional mechanical cooling when 100% outside air mode is active
A.5 When economizer is disabled, outside air dampers revert to minimum outside air mode that provides for the minimum amount of outside air necessary.
55
Section 503.2.10 Systems Performance Verification and Completion (Continued)
Context:
1. 2012 IECC dedicates separate chapter to commissioning (Cx) requirements
2. Cx for buildings >50K ft2 as a starting point for code requirements
3. Current proposal provides a testing ground for future Cx requirements in VT, utilizing only large buildings
4. Feedback from use of 2012 IECC and VT requirements will be helpful for next update of VT code
5. Performance verification should ensure systems comply with code intent and operating at maximum energy efficiency
6. Performance verification improves building performance, hopefully reduces contractor call-backs, issues.
56
Section 503.3.1 Economizers and 503.4.1 Economizers (Complex HVAC Systems)
1. Economizers required on all systems ≥ 54,000 Btu/h (2005 CBES ≥ 65,000 Btu/h)
2. Defined allowable economizer sequences to align with ASHRAE 90.1-2007
3. Clarified section 503.4.1 using improved language from 2012 IECC
a. Design Capacity
b. Maximum Pressure Drop
c. Integrated Economizer Control
57
Section 503.3.1 Economizers and 503.4.1 Economizers (Complex HVAC Systems)
DEVICE TYPE REQUIRED HIGH LIMIT (ECONOMIZER OFF WHEN):
EQUATION DESCRIPTIONFixed dry bulb TOA>70°F Outdoor air temperature exceeds 70°F
Differential dry bulb TOA>TRAOutdoor air temperature exceedsreturn air temperature
Fixed enthalpy hOA> 28 Btu/lbaOutdoor air enthalpy exceeds 28 Btu/lb of dry air
Electronic Enthalpy (TOA , RHOA) > BOutdoor air temperature/RH exceeds the "B" setpoint curve
Differential enthalpy hOA> hRAOutdoor air enthalpy exceeds return air enthalpy
Dew-point and dry bulb temperatures
DPOA > 55°F or TOA>70°F
Outdoor air dry bulb exceeds 70°F or outside dew point exceeds 55°F (65 gr/lb)
Table 503.3.1.1.3(2) HIGH-LIMIT SHUTOFF CONTROL SETTING FOR AIR ECONOMIZERS
58
Section 503.4: Additions from ASHRAE 90.1
• 503.4.2.1 Static Pressure Sensor Location language
• 503.4.3.4 Hydronic variable flow systems language
• 503.4.3.6 Chilled and Hot Water Temperature Controls
59
SECTION 504:SERVICE WATER HEATING
60
Section 504.1.1 Electrical Water Heating Limitation
Electric service water heating units shall be limited to a maximum of 5 kW total power input
Context: This is carried over from 2005 CBES
61
Section 504.7.2 Covers
Hot tubs and spas heated to more than 90°F(32°C) shall have a cover with a
minimum insulation value of R-12.
62
SECTION 505:ELECTRICAL POWER AND
LIGHTING SYSTEMS
63
Section 505.5.2 Interior Lighting PowerBuilding Area Method and Space by space Method
included
Lighting Power Density values equal to 2012 IECC
• 2009 IECC equal to 2005 CBES
• 2012 IECC values include revised categories, higher efficiency for certain categories, and scaled back values for others
64
Table 505.5.2.1 Interior Lighting Power Allowances
• All others unchanged from 2005 CBES
Space Type 2005 VT
CBES (W/SF)
2009 IECC
(W/SF)
2011 VT CBES (W/SF)
Office 1.0 1.0 0.9
Retail 1.5 1.5 1.4
Fire Station 1.0 1.0 0.8
Warehouse 0.8 0.8 0.6
Building Area Method
65
Table 505.5.2.2 Interior Lighting Power Allowances
Space Type 2005 VT CBES (W/SF)
2011 VT CBES (W/SF)
Conference/Meeting/Multipurpose
1.3 1.2
Corridor/Transition 0.5 0.7Electrical/Mechanical
1.5 1.1
Office - Enclosed N/A 1.1 1.1Office - Open Plan 1.1 1
Space by Space Method – Common Space Types
66
Table 505.5.2.2 Interior Lighting Power Allowances
Space Type 2005 VT CBES (W/SF)
2011 VT CBES (W/SF)
Healthcare Clinic/Hospital
Exam/Treatment 1.5 1.7
Radiology/Imaging 0.4 1.3
Hotel - Lobby 1.1 2.1Warehouse –Medium/Bulky Material
0.9 0.6
Space by Space Method – Building Specific Space Types
67
Table 505.5.2 – FootnotesAdditional Retail Lighting Power Allowance
Additional Interior Lighting Power Allowance = 1000 watts +
(Retail Area 1 x 0.6 W/ft2) +
(Retail Area 2 x 0.6 W/ft2) +
(Retail Area 3 x 1.4 W/ft2) +
(Retail Area 4 x 2.5 W/ft2),
Where:
Retail Area 1 = the floor area for all products not listed in Retail Area 2, 3 or 4.
Retail Area 2 = the floor area used for the sale of vehicles, sporting goods and small electronics.
Retail Area 3 = the floor area used for the sale of furniture, clothing, cosmetics and artwork.
Retail Area 4 = the floor area used for the sale of jewelry, crystal, and china.
Intent: Allow flexibility in design for
critical retail applications!
68
Table 505.5.2.2 Interior Lighting Power Allowances
Space by Space Method – Decorative Lighting
•Additional allowance of 1 W/SF for decorative lighting no longer exists
69
Daylight Zone ControlDaylight zones
• Must have individual control of the lights independent of general area lighting
What is a “daylight zone”?
70
Daylight Zone Definition –Under Skylights
• The area under skylights whose horizontal dimension, in each direction, is equal to the skylight dimension plus the smaller of:• The floor-to-ceiling height, or
• The distance to a ceiling height opaque partition, or
• One-half the distance to adjacent skylights or windows
71
Daylight Zone Definition –Adjacent to Vertical Fenestration
The daylight zone depth is assumed to be 15 feet into the space or to the nearest ceiling height opaque partition, whichever is less
The daylight zone width is assumed to be:
• the width of the window plus 2 feet on each side, or
• the window width plus distance to opaque partitions, or
• the window width plus one-half the distance to adjacent skylight or vertical fenestration, whichever is least.
Read: “Next to a Window”
72
Table 505.6.2(1) Exterior Lighting Zones
Lighting Zone Description
1 Developed areas of national parks, state parks, forest land, and rural areas
2 Areas predominantly consisting of residential zoning, neighborhood business districts, light industrial with limited nighttime use and residential mixed use areas
3 All other areas
4 High-activity commercial districts in major metropolitan areas as designated by the local land use planning authority
73
505.6.2 Exterior Lighting Power Limits What areas are covered under
exterior lighting allowances?
• Tradable surfaces
Common exterior lighted needs that can be traded for other needs.
For example, wattage allowed for parking lot lighting can be “traded” and used for canopy lighting.
• Nontradable surfaces
Less common exterior lighted needs that cannot be traded for other needs.
These applications have more specific security or task illuminance needs.
74
Table 505.6.2(2) Exterior Lighting Power Allowances
Zone 1 Zone 2 Zone 3 Zone 4Base Site Allowance
500 W 600 W 750 W 1300 WTradable Surfaces Uncovered Parking Areas
Parking areas and drives 0.04 W/ft2
0.06 W/ft2 0.10 W/ft2 0.13 W/ft2
Building Grounds
Walkways less than 10 feet wide
0.7 W/linear foot
0.7 W/linear foot
0.8 W/linear foot
1.0 W/linear foot
Walkways 10 feet wide or greater
0.14 W/ft2 0.14 W/ft2 0.16 W/ft2 0.2 W/ft2
Plaza areas
Special Feature Areas
Stairways 0.75 W/ft2 1.0 W/ft2 1.0 W/ft2 1.0 W/ft2
Pedestrian Tunnels 0.15 W/ft2 0.15 W/ft2 0.2 W/ft2 0.3 W/ft2
75
• Vermont Department of Public Service
http://publicservice.vermont.gov/energy/ee_commstandards.html
• Readable version of 2011 CBES (non-printable)
• Efficiency Vermont CBES Information
• http://www.efficiencyvermont.com
• Go to “Partners” section for Design Professionals and Engineers
Additional Resources
76
Questions/Discussion
Efficiency Vermont is a Registered Provider with The American Institute of Architects Continuing Education Systems (AIA/CES). Credit(s) earned on completion of this program will be reported to AIA/CES for AIA members. Certificates of Completion for both AIA members and non-AIA members are available upon request.
This program is registered with AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product.
Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.
LEARNING OBJECTIVES
Understand basic background and history of Vermont’s
energy code.
Understand the basic requirements for meeting
Vermont’s 2011 RBES and CBES.
Understand differences between applicability of RBES
vs. CBES in specific project scenarios.
Learn what methods can be used to show compliance
with RBES and CBES.
Course EvaluationsIn order to maintain high-quality learning experiences, please
access the evaluation for this course by logging into CES Discovery and clicking on the Course Evaluation link on the
left side of the page.
THE VERMONT RESIDENTIAL ENERGY
CODE
WHICH BUILDINGS MUST COMPLY?
• New residential construction, 3 stories or less– Does not include commercial buildings
– But does include residential part of mixed-use buildings
• Existing low-rise residential buildings– Additions
– Only the addition needs to conform
– Gut renovations,
– Does not require code levels of insulation for renovation, but must fill cavities if exposed
• Replacement windows
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EXEMPTIONS
• Extreme low energy use – less than 1 watt per square foot peak load
• Mobile homes– Title VI, National Manufactured Housing Construction &
Safety Standards Act of 1974
– Site-constructed components still must comply
• Buildings (or areas) not heated or cooled
• Historical buildings
• Hunting camps
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LOG HOMES
• Vermont code distinguishes between log homes
and everything else
• In general, log homes are allowed to be less
efficient
• But there are more stringent requirements for other parts of
the building to partially make up for the difference
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OWNER/BUILDER PROJECTS
• Specifically exempted from meeting the technical requirements of the code
• Owner must direct the details of construction, including energy items, must live in the building
• Must do calculations, complete and file the Owner/Builder Disclosure Statement
• Must disclose in writing to potential buyers before purchase and sale agreement
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LIABILITY
• Homeowner may take civil action against
person certifying building
• Damages may include increased energy
costs and costs to bring the building into
compliance (as well as court, attorneys’ fees)
• Claims must be filed within six years
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WHAT’S REQUIRED?
• Basic Requirements
• Performance Requirements -- Three Methods
“Fast Track” method
VTcheck Software
Home Energy Rating
• Certification
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BASIC REQUIREMENTS
• Air Tightness
• Vapor Retarder
• Ducts
• Thermostats
• Solid Fuel Appliances
• Ventilation & Combustion Air
• Window U-value
• Pipe Insulation
• Lighting
• Equipment Sizing
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AIR LEAKAGE
• Air leakage locations must be sealed
• Applies to leakage points between:
– Conditioned space and outside
– Conditioned and unconditioned spaces
• Testing option
– Blower Door test, less than 5 ACH @ 50Pa
• Visual inspection option
– Detailed checklist
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BASIC REQUIREMENTS
ACCESS HATCHES
• Access doors must be weatherstripped and
insulated to a level equivalent to the insulation on
the surrounding surfaces.
• Access must be provided to all equipment that
prevents damaging or compressing the insulation.
• A wood framed or equivalent baffle or retainer is
required when loose fill insulation is installed.
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BASIC REQUIREMENTS
VAPOR RETARDER
• Class I or II (aluminum foil, poly, kraft facing)
required on frame walls
• Except basement walls & below grade walls
• Class III (paint) allowed if:
• Vented cladding over fiberboard or gypsum
• Insulated sheathing R-7.5 on 2x4 wall
• Insulated sheathing R-11.25 on 2x6 wall
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BASIC REQUIREMENTS
DUCTS
• All ducts must be air sealed
• Ducts outside thermal envelope must be insulated
to the same R-value as required for immediately
adjacent surfaces
• If air handler or any ductwork is located outside
conditioned space, ducts must be tested
• Less than 6 CFM@25 Pa leakage to outdoors per 100 sq ft
conditioned floor area
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BASIC REQUIREMENTS
HEATING CONTROLS
• Programmable thermostat required if furnace, heat
pump or boiler
• Not required for space heaters, solid fuel or spaces
served by radiant floors
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BASIC REQUIREMENTS
COMBUSTION AIR FOR GAS & OIL
• All chimney-vented gas and oil appliances must
have combustion air as specified in the gas and
oil codes (NFPA 54 & 31)
• All new homes are “unusually tight construction” as
defined in the gas & oil codes, so air must be supplied,
regardless of the volume of the space Also, taking
combustion and dilution air from attics or crawl spaces is
specifically prohibited
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BASIC REQUIREMENTS
CHIMNEYS
• All chimney-vented oil and gas equipment must
establish spill-free draft within 2 minutes under worst-
case conditions
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BASIC REQUIREMENTS
SOLID FUEL COMBUSTION
• Must have gasketed doors with compression closure
or compression latch system
• Solid fuel combustion air must be delivered directly
to the firebox (except older stoves where not
possible)
• Site-built exterior air inlets must meet detailed
installation requirements19
BASIC REQUIREMENTS
MECHANICAL VENTILATION
• Whole house ventilation
• Including local exhaust
• Automatic controls
• Minimum flow rates – two options
• Install minimum rated capacity fan, or
• Measure system flow
• Installation requirements
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BASIC REQUIREMENTS
WINDOW EFFICIENCY
• The average area-weighted U-value of windows
may not exceed 0.32
• Skylights may not exceed U-0.55
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BASIC REQUIREMENTS
LIGHTING
• At least 50% of lighting fixtures must be high-
efficiency lamps
• CFL or equivalent
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BASIC REQUIREMENTS
SYSTEM SIZING
• Air conditioners and heat pumps must not be
oversized by more than 15%
• Fuel-fired appliances must not be oversized by
more than 40%
• Or use smallest available unit
• Manual J & S or other approved methodology
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BASIC REQUIREMENTS
COMPLIANCE METHODS
• “Fast Track” Method
• Software Method
• Home Energy Rating
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FAST TRACK METHOD
• Advantages
• Simplest method
• Minimal calculations
• Drawbacks
• Least flexible, limited types of homes
• Glazing area cannot exceed 20% of wall area
• Must comply with conditions
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FAST TRACK: PROCESS
• Calculate glazing percent area
• Find the right Fast Track table for your building type
• Choose desired package
• Complete and file Certificate after building is finished
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CONDITIONS FOR TABLES
• Basement wall insulation must extend from the top of the wall to the floor
• Crawl space wall insulation must go from top of wall to at least 12” below grade
• Minimum slab edge insulation
• Floors over outside air insulated as per attics
• Higher R-value in attics if diminished at eaves
• 1% of window area and one door exempt
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FAST TRACK METHOD
FAST TRACK TABLE
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SOFTWARE METHOD
Advantages• Easy to try variations, update changes• Reduces calculation time and errors• Use for wide variety of designs• Do-it-yourself, with basic computer skills• Generates report automatically
• Drawbacks• Requires a computer and basic skills• Need to calculate all areas of thermal envelope,
not just window and wall
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2/10/2012 30
HOME ENERGY RATING
Advantages– High degree of flexibility– Calculations done by energy specialist– Gives credit for air sealing and passive solar gains (can be
easier to pass)
Drawbacks– Complete building design required
Can pay for the rating, but most are done for free through the Vermont Energy Star Homes Program
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THE CERTIFICATE
• Provides:– Details about the house – Builder’s word that house
meets code
• Fill out & file– Post in house, record with
town, copy to Public Service Dept
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SUMMARY -- WHAT’S REQUIRED?
• Basic Requirements
• Performance Requirements -- Three Methods
“Fast Track” Method
Software Method
Home Energy Rating
• Certification
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RESOURCES
• Energy Code Assistance Center• 1-855-887-0673• www.efficiencyvermont.com/for_our_partners/res_
nc_partners/energy_code_assistance.aspx• Department of Public Service
• publicservice.vermont.gov/energy/ee_resbuildingstandards.html
• Efficiency Vermont• Energy Code Plus• Vermont ENERGY STAR Homes
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Background on Energy Codes in VT
Energy Codes Background in Vermont
History Residential Building Energy Standards (RBES):
1997, 2005, 2011 Commercial Building Energy Standards (CBES):
2001, 2005, 2011
Compliance Rates Residential:
72 +/-% in 2008 Current market study: NMR – REScheck – performance based
assessment Commercial:
Current market study: Navigant – DOE Building Energy Codes Program – modified to 2005 CBES
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2011 Energy Codes Update
CBES: January 3rd 2012 effective date. House Bill H.643 MAY change the effective date.
RBES: October 1st 2011 effective date.
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Code Compliance
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Code Compliance
Vermont is not really behind other states just because we don’t have a code enforcement infrastructure. We may actually be in a better position to build a new system from scratch since we aren’t hindered by an existing system.
Public Review Draft of the Code Compliance Draft is available on the DPS website.
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Enforcement
CBES Certificate
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Enforcement
Enforcement: DPS has responsibility for overseeing code and
monitors for non-compliance
Working closely with the Division of Fire Safety. Initial plan review for permitting. Inspection for issuance of CO.
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Barry MurphyDepartment of Public [email protected]: 802-828-3183
Contacts