2011 Vermont Commercial Building Energy Standards (CBES) · 2020-01-31 · with the 2011 VT CBES? 1. Chapter 5 - General Prescriptive Approach •Use for ≤40% of gross wall area

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2011 Vermont Commercial Building Energy Standards (CBES)

February 9, 2012Efficiency Vermont—Better Buildings By Design

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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.

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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.

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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.

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Overview

•CBES Update Process

•Administration

•General Requirements

•Envelope

•Mechanical Systems

•Service Water Heating

•Electrical Power and Lighting

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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

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CBES Update Process

2011 VT CBES

2007/2010 ASHRAE

90.1

2005 VT CBES

2009/2012 IECC

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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

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VERMONTCOMMERCIAL BUILDING

ENERGY STANDARDS (CBES)

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CHAPTER 1:ADMINISTRATION

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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)

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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

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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…

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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]

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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

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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

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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.

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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

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CHAPTER 3:GENERAL REQUIREMENTS

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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”

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CHAPTER 5: COMMERCIAL ENERGY EFFICIENCY

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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

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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

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SECTION 502:BUILDING ENVELOPE

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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

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Building Envelope502.2.1:Roof Assembly

Skylight and mechanical curbs required to insulate skylight to at least R-5

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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.

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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

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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

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Building Envelope: Above-Grade Walls

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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

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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

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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-

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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

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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

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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

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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

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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.

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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:

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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

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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.

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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

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SECTION 503:BUILDING MECHANICAL

SYSTEMS

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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

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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)

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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

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Simple Versus Complex Systems

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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)

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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.

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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

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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.

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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

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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.

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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

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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

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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.

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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.

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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.

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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

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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

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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

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SECTION 504:SERVICE WATER HEATING

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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

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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.

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SECTION 505:ELECTRICAL POWER AND

LIGHTING SYSTEMS

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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

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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

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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

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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

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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 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!

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Space by Space Method – Decorative Lighting

•Additional allowance of 1 W/SF for decorative lighting no longer exists

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Daylight Zone ControlDaylight zones

• Must have individual control of the lights independent of general area lighting

What is a “daylight zone”?

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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

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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”

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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

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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.

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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

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• 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

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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

6

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

7

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

8

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

9

WHAT’S REQUIRED?

• Basic Requirements

• Performance Requirements -- Three Methods

“Fast Track” method

VTcheck Software

Home Energy Rating

• Certification

10

BASIC REQUIREMENTS

• Air Tightness

• Vapor Retarder

• Ducts

• Thermostats

• Solid Fuel Appliances

• Ventilation & Combustion Air

• Window U-value

• Pipe Insulation

• Lighting

• Equipment Sizing

11

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

12

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.

13

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

14

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

15

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

16

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

17

BASIC REQUIREMENTS

CHIMNEYS

• All chimney-vented oil and gas equipment must

establish spill-free draft within 2 minutes under worst-

case conditions

18

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

20

BASIC REQUIREMENTS

WINDOW EFFICIENCY

• The average area-weighted U-value of windows

may not exceed 0.32

• Skylights may not exceed U-0.55

21

BASIC REQUIREMENTS

LIGHTING

• At least 50% of lighting fixtures must be high-

efficiency lamps

• CFL or equivalent

22

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

23

BASIC REQUIREMENTS

COMPLIANCE METHODS

• “Fast Track” Method

• Software Method

• Home Energy Rating

24

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

25

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

26

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

27

FAST TRACK METHOD

FAST TRACK TABLE

28

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

29

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

31

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

32

SUMMARY -- WHAT’S REQUIRED?

• Basic Requirements

• Performance Requirements -- Three Methods

“Fast Track” Method

Software Method

Home Energy Rating

• Certification

33

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

34

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

2

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.

3

Code Compliance

4

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.

5

Enforcement

CBES Certificate

7

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.

8

Barry MurphyDepartment of Public [email protected]: 802-828-3183

Contacts