BASELINE CHARACTERISTICS

OF THE 2002-2004 NONRESIDENTIAL SECTOR:

SEATTLE CITY LIGHT

For the

Northwest Energy Efficiency Alliance

David Baylon

Final Report October 31, 2008

Ecotope, Inc. i

Table of Contents

1. Introduction ................................................................................................................. 1

2. Sample Design .............................................................................................................. 1

3. Building Characteristics ............................................................................................. 2

3.1. Lighting ....................................................................................................................................... 2 3.2. HVAC ......................................................................................................................................... 5 3.3. Building Envelope .................................................................................................................... 10

3.4. Building Commissioning .......................................................................................................... 13 3.5. Operations / Training ................................................................................................................ 14 3.6. LEED

® Buildings ...................................................................................................................... 15

4. Energy Use and Energy-Use Intensities (EUIs) ...................................................... 15

5. Interviews with Architects and Designers .............................................................. 18

5.1. Interview Sample ...................................................................................................................... 19

5.2. Energy Codes ............................................................................................................................ 19

5.3. Attitudes Toward Energy Efficiency ........................................................................................ 20

6. Overall Observations ................................................................................................ 22

7. References .................................................................................................................. 24

Ecotope, Inc. ii

Table of Tables

Table 2.1: Sample Population by Building Type (N) ................................................................................. 2 Table 3.1: Distribution of Lamp Type (% of Total Lighting Watts) .......................................................... 3 Table 3.2: Distribution of Lighting Controls (% of Floor Area Controlled by Particular Strategy) .......... 3 Table 3.3: LPD by Building Type (Watts/sq. ft.) ....................................................................................... 4

Table 3.4: Actual LPD Code Requirements (Watts/sq. ft.) ........................................................................ 5 Table 3.5: Lighting Code Compliance Results ........................................................................................... 5 Table 3.6: HVAC Systems by Building Type (% Floor Area) ................................................................... 6 Table 3.7: Heat Source Type by Building Type (% Floor Area) ................................................................ 7 Table 3.8: Cooling Source Type (% Floor Area) ........................................................................................ 8

Table 3.9: Average Cooling Equipment Efficiency and Code Compliance (SCL Sample) ....................... 9 Table 3.10: Average Heating Efficiency and Code Compliance (SCL Sample) ...................................... 10 Table 3.11: Building Heat Loss Rate (UA/sq. ft.) .................................................................................... 10

Table 3.12: Window Area by Building Type (% of Gross Wall) ............................................................. 11 Table 3.13: Window U-Factor by Building Type (% of Glazing Area) ................................................... 12 Table 3.14: Window SHGC Category (% of Window Area) ................................................................... 12

Table 3.15: Envelope Code Compliance by Code (% and N) .................................................................. 13 Table 3.16: Reported Commissioning by Building Type ......................................................................... 14 Table 3.17: Operator Training as Reported by Building Operators (% of Buildings) .............................. 14

Table 3.18: LEED Certified Buildings Observed (N) .............................................................................. 15 Table 4.1: Total EUI summary (kBtu/sq. ft.) ............................................................................................ 16

Table 4.2: Total EUI summary (kWh/sq. ft.) ............................................................................................ 16 Table 4.3: Electric Only EUI summary (kWh/sq. ft.) ............................................................................... 17 Table 4.4: Adjusted EUIs from CBSA Regional Study (1990-2000 Cohorts) and CBECS..................... 17

Table 5.1: Interview Sample Distribution by Design Role ....................................................................... 19 Table 5.2: Reactions to Energy Code Provisions...................................................................................... 19

Table 5.3: Plan Reviewer or Building Official Feedback (%) ................................................................. 20 Table 5.4: Percent of Respondents Claiming “Beyond Code” in their Designs ....................................... 20

Table 5.5: Importance of Energy Efficiency to the Design Team (%) ..................................................... 20 Table 5.6: LEED

® Requested by Clients .................................................................................................. 21

Table 5.7: Opportunities to Promote Energy Efficiency .......................................................................... 21

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1. Introduction This summary presents the 2002-2004 baseline characteristics of nonresidential buildings within

the service territory of Seattle City Light (SCL). The summary is a breakout of utility specific

data collected as part of a larger regional study, Baseline Characteristics of the 2002-2004

Nonresidential Sector: Idaho, Montana, Oregon, and Washington (Baylon and Kennedy 2008).

The main research activities for the regional study included field visits and interviews with

design professionals and building operators. Please refer to the full report for a description of the

regional sample and characteristics of nonresidential buildings by state and building type.

Additionally, not all of the characteristics summarized in the full report are summarized here.

This is due to the insignificant number of cases available to generate certain comparisons (such

as building components compared by building type).

The Seattle City Light summary presents the following information:

Building Characteristics. General characteristics and specific characteristics associated

with the major energy-using components (lighting, HVAC, and envelope) of commercial

buildings. This information includes identification of building components, equipment,

and controls used in each building.

Energy Code Compliance. Energy code compliance is assessed for lighting, HVAC, and

envelope components.

Energy Use and Energy Use Intensities (EUIs). EUIs are presented by building type

within the SCL sample.

Interviews with Architects and Designers. Insights into the attitudes among design

professionals active in the commercial sector toward energy conservation, sustainable

design, and related practices.

2. Sample Design As part of the regional study a stratified random sample was designed to be representative of new

commercial construction in Idaho, Montana, Oregon, and Washington. The study included

development of a sample frame drawn from the F.W. Dodge® database. For a detailed

description of the techniques and design of the regional sample please see Section 3 of the

2002-2004 Baseline Study.

Individual utilities requested enhancements to the regional sample to allow their particular

service territories to be characterized independently. These samples were designed with the

same stratification boundaries used to develop the state samples. This allowed the maximum

overlap between the enhanced samples and the state samples, and thereby allowed the maximum

coverage for the particular utility service territories.

Seattle City Light requested additional buildings to ensure a statistically representative sample

for its service territory and allow more robust comparisons between its population and others in

the study. In addition, a few buildings were added within Seattle City Light’s sample to allow a

partial characterization of buildings certified by the U.S. Green Building Council’s (USGBC)

Leadership in Energy and Environmental Design (LEED®

) program. There were several

2

buildings in the original sample that were LEED certified. The utility asked for three buildings

to be added to complete a contemporary picture of this program in the Seattle area. Ultimately,

six LEED buildings were included in the sample. Two of these buildings were drawn from the

utility records and had no representation in the sample frame used for the rest of the study. For

this purpose the buildings added were not included in the characteristics summaries unless they

could be weighted from the original sample frame. They are included in a separate summary

focused on LEED certified buildings (Baylon, 2008).

Table 2.1 shows the final sample drawn for Seattle City Light, including both the overlap with

the state samples and the utility enhanced sample. This table does not include sample points that

were only part of the building type sample.

Table 2.1: Sample Population by Building Type (N)

Building Type SCL Washington Regional

Assembly 2 4 8

College 1 2 9

Schools 7 30 67

Grocery 0 10 18

Health Services 2 6 16

Hospital 4 13 25

Institution 3 10 23

Office 1 8 27

Other 0 2 9

Residential/Lodging 4 11 18

Restaurant / Bar 0 1 8

Retail 7 32 78

Warehouse 1 17 40

Total 32 146 346

3. Building Characteristics This section summarizes characteristics associated with the major energy using components

(lighting, HVAC, and envelope,) of commercial buildings in the Seattle City Light service

territory. This information includes identification of building components, equipment, and

controls used in each building. This section also outlines information collected on building

commissioning, operations/training, and LEED status.

The regional study also reviewed refrigeration systems; however, due to the insignificant number

of refrigeration system within each utility sample, these systems are not summarized in the

supplemental utility reports.

3.1. Lighting

Individual fixtures, lamps, and control strategies and technologies were determined using a

combination of plan review and field audit. The tables in this section present Seattle City

Light results for lighting technologies, lighting controls, and lighting power densities (LPD).

3

Lamps were divided into five classes: compact fluorescent (CFL), linear fluorescent (LF),

high intensity discharge (HID), incandescent (INC), and other.

Table 3.1 shows the distribution of lighting wattage by these classes. In cases where

particular samples have a large amount of residential type uses (e.g., motels, assisted living)

the fraction of incandescent lighting increases.

Table 3.1: Distribution of Lamp Type (% of Total Lighting Watts)

Building Type CFL LF HID INC Other Total

Assembly 24 53 10 13 0 100

College 40 7 0 53 0 100

Schools 9 64 26 2 0 100

Grocery — — — — — —

Health Services 14 71 0 16 0 100

Hospital 11 73 2 12 2 100

Institution 19 67 6 6 1 100

Office 10 77 0 13 0 100

Other — — — — — —

Residential / Lodging 26 24 0 25 25 100

Restaurant / Bar — — — — — —

Retail 5 65 20 10 0 100

Warehouse 0 13 81 6 0 100

Weighted Average (SCL) 15 56 14 11 4 100

Region 9 58 17 14 1 100

Table 3.2 presents the distribution of lighting controls. Lighting control has been

summarized into the following major categories observed throughout the sample:

Sweep control enables the building lighting to be shut off during unoccupied hours.

Lighting EMS integrates the lighting control into a central system with the HVAC

and other building systems.

Daylighting control provides an automatic system for turning off portions of a

building lighting system with the availability of daylight from windows or skylights.

Occupancy sensors monitor room or area occupancy and turn off lights when the

room in unoccupied.

Multi-level switching allows occupants to reduce lighting levels manually as lighting

needs change.

Table 3.2: Distribution of Lighting Controls (% of Floor Area Controlled by Particular Strategy)

Control Type SCL Washington Region

Sweep 42 39 37

Lighting EMS 58 41 34

Daylighting 61 25 18

Occupancy 70 46 47

Multi-Level Switching 41 34 39

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Lighting power densities are summarized in Table 3.3. This summary includes all lights

in the building, both interior and exterior. Lighting that is exempted from the energy

code (e.g., security lighting, dental and medical lighting) has been included in this

summary if it is permanently installed in the building (not included with furnishings etc.).

It should be noted that these summaries are the relevant summaries for the buildings

surveyed. All buildings have some variation in LPD given the particular mix of

exemptions, and exterior lighting that were selected by the designer and builder. The

code regulates most of these exemptions separately outside the LPD allowances. Thus,

the comparison tables do not really reflect the relative severity of these requirements only

the mix of responses and requirements that the particular buildings in the sample

experienced.

Table 3.3 also includes a summary of the results of the 2000 building stock assessment

done for Seattle City Light. The nature of the 2000 sample is that it included much more

specialty retail than this study. While there have been improvements in the LPDs of the

retail sector (especially display lighting) the apparent change in this table is the result of

the major differences between these two samples. The baseline “office” sample is more

limited in large part because the construction of large offices was more limited in the

2002-2004 time period. The few buildings built included only LEED projects, which

probably reduced the LPD substantially. Aside from these sectors, the LPDs observed in

this sample are comparable to the previous sample.

Table 3.3: LPD by Building Type (Watts/sq. ft.)

Building Type SCL SCL 2000 Washington Region

Assembly 1.11 — 1.04 1.05

College 0.98 1.11 1.01 1.03

Schools 1.14 1.18 1.12 1.10

Grocery — 1.59 1.57

Health Services 1.47 1.35 1.33 1.36

Hospital 1.26 — 1.17 1.26

Institution 0.99 — 0.95 1.10

Office 0.74 .99 1.02 1.03

Other — .86 0.81 0.85

Residential/Lodging 1.18 — 1.35 1.23

Restaurant / Bar — 2.66 1.77 1.43

Retail 1.23 2.39 1.48 1.37

Warehouse 0.79 .77 0.72 0.58

Weighted Average 1.14 — 1.16 1.08

3.1.1. Lighting Code Compliance

Each state regulates lighting using a lighting power allowance. Table 3.4 summarizes the

lighting power allowance applied to the particular buildings in the utility sample. For

Seattle, there is a separate code that applies to buildings in that jurisdiction.

Table 3.5 summarizes the level of compliance in the utility area and compares it to the

level of lighting code compliance in the state and region. It should be noted that for this

table only code compliance is summarized against the codes enforced in the jurisdiction

where the building is located.

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Table 3.4: Actual LPD Code Requirements (Watts/sq. ft.)

Mean Code

LPD Std. Dev. N

SCL 1.31 .33 28

Washington 1.26 0.38 146

Region 1.31 0.45 347

Table 3.5: Lighting Code Compliance Results

Compliance (%) N

SCL 89 28

Washington 78 146

Region 79 346

3.2. HVAC

Auditors collected HVAC system characterization information and detailed specifications for

heating, ventilation, and cooling equipment.

3.2.1. HVAC System Types

Table 3.6 summarizes the main HVAC systems and their delivery systems. HVAC

systems were categorized by system type and whether water was used to deliver space

conditioning (heating, cooling, or both). DX cooling units and gas furnaces are included

as hydronic if they used water as the main working fluid.

Descriptions of HVAC system types:

Zone/Unit Heater (Z/UH). Single-zone, ductless, direct heating and/or cooling

equipment as well as passive radiation baseboard and heated floors that utilize hot

water.

Single-Zone (SZ). CV, single-zone, ducted systems. This type of system is the most

common type of system and is generally associated with rooftop package systems.

Single-Zone VAV (SZ-VAV). Systems with a single-zone air handler with variable

flow. Flow in heating mode is at a minimum and then flow is ramped to meet cooling

or ventilation needs. Fan flow is varied using a VFD drive on the fan.

Multi-Zone (MZ). Systems with CV operation and reheat to condition spaces with

varying requirements. Typically, these systems have variable frequency drives

(VFD) on the central fans and many have VAV terminal boxes primarily to help with

balancing the system. The systems may have a few zones with variable flow

operation but overall the systems do not come close to meeting code requirements for

a variable flow system. These systems typically have very large heating requirements

to reheat cooled primary air. All of these systems utilize hot water reheat from a

boiler.

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Variable Air Volume (VAV). All versions of VAV systems, fanless, series, and

parallel fan-powered. Reheat is typically needed and generally adds a significant

additional heating load. Generally, hot water reheat systems dominate hospital,

college, lodging, and educational buildings. Electric reheat dominates office areas.

Institutions and health services utilize an equivalent amount of hot water reheat and

electric reheat. This category includes the “under floor air distribution” systems often

used in LEED projects.

Heat Pump Loops (HPLP). Systems that use small heat pumps to supply zone-level

conditioning. The heat pumps are connected together with a water loop that is

conditioned in part by the diversity of the loads on the heat pump loop and in part by

a boiler and cooling tower that ensures that the loop temperature is maintained within

prescribed limits.

2 Pipe/4 Pipe Fan Coil (2/4-P). These systems are a variation on water loop

conditioning and use a chilled water and/or a hot water loop to feed fan coils in all

zones. This system is common in hospital and school settings and favored because it

affords a variety of control strategies to adjacent zones.

Table 3.6: HVAC Systems by Building Type (% Floor Area)

Building Type Z/U

H SZ SZ VAV MZ VAV HPLP 2/4 P Total

Assembly 2 81 17 0 0 0 0 100

College 40 60 0 0 0 0 0 100

Schools 16 30 0 0 12 30 11 100

Health Services 2 51 0 0 47 0 0 100

Hospital 2 6 0 43 49 0 0 100

Institution 2 27 9 11 52 0 0 100

Office 0 0 0 0 93 6 0 100

Residential / Lodging 4 30 0 18 0 48 0 100

Retail 9 86 0 1 4 0 0 100

Warehouse 100 0 0 0 0 0 0 100

Weighted Average (SCL) 10 43 2 8 23 12 3 100

Washington 17 52 1 6 15 4 5 100

Region 16 52 2 4 18 4 4 100

3.2.2. Heating Type

Table 3.7 summarizes the primary heating fuel by building type. Multi-zone reheat

systems with different primary coil fuel and reheat fuel are categorized by the reheat fuel

type. Heat pump fuel includes air source and water source heat pumps. Central plants

are included in the “other” category. This category includes remote plants that were not

part of the audited project. When the fuel type for building plants was recorded, it was

included in the appropriate fuel category rather than plant. “Other” heat sources included

oil, geothermal, heat recovery, and wood waste. In addition, if no heating system was

included (especially warehouse storage facilities) these were included under “other.”

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We also compared the heating results to the summaries from the 2000 commercial

building audits and report (Baylon et al. 2001). As can be seen here there were

substantial differences between the building in this sample and the previous sample. This

is mostly explained by the relative importance of “office” uses in the 2000 study. In both

this sample and the previous sample, electric reheat accounts for about 90% of the built-

up VAV systems in Seattle. For cooling systems the saturations of chillers seems

unchanged between the two samples and the overall results of the 2002–2004 Baseline

Study.

Table 3.7: Heat Source Type by Building Type (% Floor Area)

Building Type Electric Heat

Pump

Natural

Gas Propane Other Total

Assembly 3 0 97 — 0 100

College 17 9 75 — 0 100

Schools 2 31 67 — 0 100

Grocery — — — — — 100

Health Services 1 11 88 — 0 100

Hospital 23 0 72 — 0 100

Institution 40 0 30 — 30 100

Office 94 6 0 — 0 100

Other — — — — — 100

Residential / Lodging 4 62 33 — 0 100

Restaurant / Bar — — — — — 100

Retail 4 30 66 — 0 100

Warehouse 0 0 100 — 0 100

Weighted Average (SCL) 14 20 60 — 5 100

2000 Average 58 1 22 — 17 100

Washington 15 10 69 4 2 100

Region 12 9 72 3 4 100

3.2.3. Cooling Type

The list below describes the various cooling types assessed in the study. Table 3.8

summarizes the primary cooling types by building type:

Direct Expansion (DX) Cooling. Dominates the cooling sources described here.

These systems are typically associated with packaged single-zone, constant volume

equipment though roughly 40% of all VAV systems also utilize DX cooling.

Chillers. Make up the next most common cooling type. These chillers typically

provide chilled water to fan coils or other air handlers throughout the building. Air-

cooled units represent a total of 60% of all chiller capacity installed.

Water Source Heat Pumps (WSHP). Refers to equipment served by a water loop.

These systems typically utilize a cooling tower to dump loop heat.

Evaporative Cooling is used very sparingly. Most of the evaporative cooling

reported results from a single home improvement chain.

Cold Ground Water. Utilized directly by a few buildings to provide cooling.

8

Economizer-Only. Cooling utilized in all states. In this case, an air handler has a

full economizer setting that is activated by a cooling thermostat. No additional

mechanical cooling is provided in these systems.

No Cooling. A large fraction of building floor area has no cooling. These areas are

dominated by warehouse type activities.

Table 3.8: Cooling Source Type (% Floor Area)

Building Type DX WSHP Evap Chiller Plant Ground Econo None

Assembly 88 0 0 0 — — 6 6

College 60 0 0 0 — — 0 40

Schools 11 30 0 20 — — 6 34

Grocery 0 0 0 0 — — 0 0

Health Services 49 0 0 47 — — 0 4

Hospital 6 0 0 91 — — 0 2

Institution 56 0 0 26 — — 15 3

Office 2 6 0 91 — — 0 1

Other 0 0 0 0 — — 0 0

Residential / Lodging 20 48 3 0 — — 23 7

Restaurant / Bar 0 0 0 0 — — 0 0

Retail 88 0 0 0 — — 0 12

Warehouse 31 0 0 0 — — 0 69

Weighted Average

(SCL)

44 11 0 23 — — 6 15

2000 Average 75 — — 18 — — 8

Washington 49 4 1 17 2 0 5 23

Region 53 4 1 17 2 0 4 20

3.2.4. HVAC Code Compliance

Where possible, auditors collected detailed capacity and efficiency information on the

HVAC equipment found in the buildings. These data often came from plans, equipment

nameplates, O&M manuals, and occasionally manufacturers’ websites.

Each piece of equipment was assigned an energy code minimum efficiency based upon

the equipment tables adopted by the applicable code. For Idaho and Montana the codes

utilized the ASHRAE 90.1-1999 base values throughout the design window so those

were chosen as the applicable code values. Washington and Oregon adopted the

ASHRAE 90.1-1999 October 29, 2001 efficiency values in early 2002, so those values

were used for buildings there. Note that ASHRAE Standard 90.1 has become a de facto

manufacturing standard, so newly made equipment generally complies with the current

standard. The problem is that there are several effective dates for enforcing this standard

and it does not apply to equipment already manufactured.

Table 3.9 shows the result of the equipment review for cooling equipment. Table 3.10

shows the results of the review of heating equipment. In both cases the compliance rate

is based on the code tables enforced in the 2001 codes.

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Cooling equipment types:

Air conditioning equipment (AC) is the most common type of package cooling

equipment. The compressor is usually installed with a gas burner or furnace for

heating in either a package or as a split system. This category also includes split

system AC and large AC equipment in built-up systems.

Heat pumps include any and all air conditioning equipment with a reversing valve

and compressor drive heating mode. In smaller sizes (less than six tons) the rating

used is a SEER (a weighted average of performance in BTU/W in three different

operating conditions at 82°F); for larger sizes the EER is the primary rating measure

(BTU/W at a single weighting point, 95°F).

Packaged Terminal Air Conditioning (PTAC) are generally small, through-the-

wall, single-zone units with local control of temperature and air flow. These are very

common in lodging and other residential applications.

Water Source Heat Pumps (WSHP) refers to equipment served by a water loop.

These systems typically utilize a cooling tower to dump loop heat.

Table 3.9: Average Cooling Equipment Efficiency and Code Compliance (SCL Sample)

Cooling

Equipment

Seattle Region

Install Code Compliance

%

Install Compliance %

Cooling Package SEER/EER Efficiency

AC 10.5 9.7 84 10.5 85

HP 10.0 10.1 8 10.4 69

PTAC 11.0 9.9 100 10.5 100

WSHP 13.0 11.9 100 14.3 100

Chiller COP Efficiency

Air 2.9 2.8 90 3.0 95

Water 9.1 6.1 100 7.0 100

Heating equipment types:

Heat Pump (HP). All unitary heat pump equipment regulated under the HVAC

efficiency tables. These units are regulated based on size and configuration. The

efficiency shown here is the weighted average of the each heat pump observed in this

sample.

Packaged Terminal Heat Pump (PTHP). Generally small, through-the-wall heat

pumps with both compressor and condenser in a single package.

Water Source Heat Pumps (WSHP). Equipment served by a water loop. These

systems typically utilize a boiler to maintain loop temperature in heating mode.

Furnace/Unit Heater (FURN/UH). Single-zone air handlers with combustion heat

exchanger or electric resistance coils.

Boiler. The primary equipment of hot water heating systems, usually supplying heat

through a water loop.

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Table 3.10: Average Heating Efficiency and Code Compliance (SCL Sample)

Heating Equipment Seattle Region

Efficiency Compliance % Efficiency Compliance %

Electric

HP 3.5 9 3.3 93

PTHP 3.4 100 3.1 100

WSHP 4.0 86 4.1 94

FURN/UH 1.0 100 1.0 100

Combustion

FURN/UH .82 100 .82 98

Boiler .87 100 .86 100

3.3. Building Envelope

Construction techniques and insulation strategies vary dramatically within the commercial

sector. The techniques used are determined largely by building type and to a lesser degree

location. Insulation levels are driven by code requirements that do not distinguish between

individual building types. One exception to this is the use of semi-heated spaces in the

Washington codes and the use of unheated spaces in all regional codes. Table 3.11 summarizes

the building heat loss rate for the audited buildings. Given the timing of the audit, the heat loss

rate often had to be calculated without direct observation of the components. In most cases,

architectural details and specifications were used to determine the insulation values and

performance of particular components. In cases where these sources were not available, the

default values were used from the applicable code requirements. The overall heat loss rate has

been normalized by conditioned floor area. This allows the relative heat loss rate of each

building type in the samples to be reasonably comparable. The Seattle sample has about 22%

lower overall heat loss rate in spite of the increased window area shown in Table 3.12.

Table 3.11: Building Heat Loss Rate (UA/sq. ft.)

Building Type SCL N Region N

Assembly 0.26 2 0.19 8

College 0.11 1 0.11 9

Schools 0.17 7 0.14 67

Grocery — 0 0.14 18

Health Services 0.13 2 0.14 16

Hospital 0.10 4 0.11 25

Institution 0.13 3 0.17 24

Office 0.11 1 0.16 26

Other — 0 0.17 9

Residential / Lodging 0.10 4 0.12 18

Restaurant / Bar — 0 0.20 8

Retail 0.12 7 0.21 78

Warehouse 0.25 1 0.26 40

Weighted Average 0.14 32 0.18 346

11

Building components have not changed drastically since the last study. However, glazing

performance has increased to the point that low-ε coatings are nearly ubiquitous and solar

heat gain coefficients (SHGC) have been reduced. These performance improvements are

partially offset by the design trend of increased glazing areas.

The summary in Table 3.12 shows that the percentage of window area to total window area is

significantly greater in Seattle than in the state and regional level. This is true even though

the sample size for this utility service territory is only 31 buildings. This summary does not

include the two LEED buildings that were not part of the sample frame for either the city or

the region.

The distribution of high performance windows in Table 3.13 summarizes the U-value of the

windows observed. These performance values have been binned into four major categories.

This simplification was necessary to allow estimation in the absence of direct installer or

manufacturer tests of the overall window performance. Table 3.13 also reflects the improved

window performance in the Seattle sample that roughly counterbalances the increased

window area. The values in this table are the fraction of the total window area in each

building type that is assigned to the particular performance bin. For example, 26% of the

windows in the School sector are assigned values between class 30 (U=0.30) and Class 40

(U=0.40).

When the results of the 2002-2004 sample are compared to the results of the previous sample

(which were largely permitted in 1998 and 1999) there is a striking improvement in window

U-value. In some building types (especially “office”) window areas increased, but on the

whole no clear trend toward higher glazing percentage appeared across building types.

Table 3.12: Window Area by Building Type (% of Gross Wall)

Building Type SCL 2000

Sample Washington Region

Assembly 23 — 16 16

College 19 31 24 20

Schools 15 — 13 14

Grocery — 14 6 9

Health Services 34 18 26 26

Hospital 34 — 21 21

Institution 25 — 15 18

Office 55 37 31 29

Other — 19 4 10

Residential/Lodging — — 27 25

Restaurant / Bar 23 — 11 16

Retail 12 18 11 11

Warehouse 10 1 5 4

Weighted Average 22 29 15 15

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Table 3.13: Window U-Factor by Building Type (% of Glazing Area)

Building Type U-Factor Class (100 x U-factor)

30-40 41-50 51-60 >60

Assembly 1 99 0 0

College 100 0 0 0

Schools 26 66 8 0

Grocery — — — —

Health Services 0 59 42 0

Hospital 84 2 14 0

Institution 80 20 0 0

Office 79 0 21 0

Other — — — —

Residential / Lodging 92 8 0 0

Restaurant / Bar — — — —

Retail 1 83 17 0

Warehouse 0 0 0 100

Weighted Average

(SCL)

46 40 10 4

SCL 2000 Average — 27 39 33

Washington 39 33 16 13

Region 42 36 12 10

3.3.1. Solar Heat Gain Coefficient

The solar heat gain coefficient (SHGC) is largely a function of the glazing properties

rather than the frame properties. SHGC varies substantially with the types of low-ε

coating and types of glass substrate to which they are applied. The auditors attempted to

retrieve SHGC information directly from the building, the window specifications, the

window installer specifications, or the architect. Shading components were then

combined with frame information to estimate SHGC, organized into bins as shown in

Table 3.14. As with heating performance, the Seattle buildings have lower SHGC than

the remainder of the sample. This is largely the result of the addition of low-ε coatings

required to bring the overall window area into compliance.

Table 3.14: Window SHGC Category (% of Window Area)

SHGC Class (100 x U-factor)

17-35 35-54 55-86 Clear

SCL 55 26 19 0

Washington 42 35 24 2

Region 43 37 19 2

3.3.2. Building Envelope Code Compliance

Envelope code requirements differ in both style and substance across the various state

codes. As with other components in this study, the code review was based on the code

enforced in each jurisdiction in 2001. In Table 3.15, code compliance was calculated for

both the 2001 code and the 2005 code, which represents the code that would have been in

place in all of the jurisdictions in 2005.

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The Seattle Energy Code was updated during the period of this study. Trade-offs were

evaluated using the code available in 2001. As can be seen in Table 3.15, the impact of

subsequent revisions would lower the potential compliance substantially. The table

shows that for both the SCL and Washington state samples, the percentage of envelope

code compliance would decrease somewhat due to the tightened code requirements of the

2005 code.

Table 3.15: Envelope Code Compliance by Code (% and N)

State Code Year

2001 2005 N

SCL 90 82 32

Washington 94 76 148

3.4. Building Commissioning

During the review, auditors examined plans for indication of commissioning, asked on-site

staff whether commissioning was completed, and looked for commissioning documents

on-site. Table 3.16 summarizes the observed commissioning as gathered from available

documentation or from direct conversations with the building operators. There are several

large buildings in the Retail and Lodging sectors that did not report commissioning and no

evidence of commissioning reports could be found. This resulted in reduced overall

commissioning fractions although in most building types commissioning was used in the

Seattle sample. This was about twice the rate observed in the remainder of the state and

region.

Commissioning included comprehensive commissioning with reports and deficiency lists,

sites with plan notes requiring witnessed operational testing, and cases where the building

representative stated commissioning had been done. In many cases, the building

representatives participating in the audit process were not involved in construction of the

project and so may not have been aware of commissioning activities. As a result, levels of

commissioning were likely higher than this summary shows.

During this period “completion requirements” were a requirement in Washington state. It is

likely that some commissioning steps were taken in every building, however, the auditors

were not able to review commissioning documents on site and the building operator was not

aware of actual commissioning in these cases.

14

Table 3.16: Reported Commissioning by Building Type

Building Type % of Buildings

Reporting

Commissioning

% of Floor Area

Commissioned

Assembly 0 0

College — —

Schools 100 100

Grocery — —

Health Services 100 100

Hospital 100 100

Institution 100 100

Office 100 100

Other — —

Residential / Lodging 39 31

Restaurant / Bar — —

Retail 4 14

Warehouse 0 0

Weighted Average (SCL) 50 69

Washington 27 43

Region 21 37

3.5. Operations / Training

Buildings in this sample have a large amount of digital controls that allow operators more

access to individual schedules and zone controls for both HVAC and lighting.

Unfortunately, the training available for the actual building operators seems to be minimal.

Even in complex buildings when individual operators were asked, they usually did not have

any training beyond the manuals that may have been included in the building documentation.

These were usually very hard to find and even harder to discern. The commissioning

requirements under the Washington code and the ASHRAE code require commissioners to

provide a level of documentation and training to the building owner or operator. Table 3.17

shows the percent of operators interviewed that received some degree of direct operator

training either in the specifics of their particular building or as part of professionally

sponsored training for building operators. As Table 3.17 shows, approximately 30% of the

building operators in the region (that were on site during the audit period) had completed

some sort of building operator training. The buildings in the Puget Sound region were

roughly consistent with the rest of the region.

Table 3.17: Operator Training as Reported by Building Operators (% of Buildings)

Type of Training Reported

BOC† Other None

SCL 3 9 88

Washington 13 9 78

Region 13 21 68 † BOC = Building Operator Certification

15

3.6. LEED® Buildings

In this sample, eight Seattle buildings had been LEED certified by the USGBC. This group

represented approximately a third of the overall sample and over 50% of the total floor area

reviewed in Seattle. The impact of this sample was increased somewhat by the addition of

two buildings beyond the buildings that were drawn from either the regional random sample

or the enhanced sample for Seattle. Even without these added buildings, 43% of the building

area in the SCL sample was LEED certified. A detailed description of these buildings and a

comparison with other LEED buildings is included in a separate report (Baylon and Storm

2008). Table 3.18 summarizes the LEED certified buildings included in this report.

Since the LEED program was only proposed in 1999, the cohort of buildings sampled in this

study is among the early adopters for this program. In virtually every case, their LEED

participation corresponded to their participation in SCL’s “ESS” commercial energy

efficiency incentive programs.

Table 3.18: LEED Certified Buildings Observed (N)

4. Energy Use and Energy-Use Intensities (EUIs) As a part of the field protocol developed for the 2002–2004 Baseline Study auditors were asked

to get signed releases allowing the utility to release energy bills. This was supplemented with

meter numbers when available. Several problems arose in the regional sample that reduced the

number of bills that could be collected. In the SCL sample about 70% of the buildings

participated and had sufficient bills to summarize their particular energy use. In the regional

sample as a whole, only about 55% of the sample could be included in this analysis. A detailed

comparison and explanation of the development of this billing analysis is included in the EUI

supplement (Baylon and Robison 2008) to the 2002–2004 Baseline Study. In addition, the

LEED sample also includes additional summaries of the energy bills from that subset of the

regional sample. For this summary we have included a total line that is meant to give the

weighted average of the EUIs across each sample. While such a summary is traditional in

reporting EUI data, it is potentially very misleading since the average depends on the relative

number of buildings with large energy use (e.g., Hospitals, Groceries) and low energy use (e.g.,

Warehouses). The sample as it finally appears in these summaries is a subset of the initial

representative sample and, unfortunately, the amount of non-response in developing the EUIs

compromises the meaning of the “Total” entry.

For this summary the energy use of each building was normalized by the size of the building. In

addition, the various energy and fuel use was converted to a set of common units. KBtu/sq. ft.

was the resulting Energy Use Intensity (EUI) used in evaluating the buildings of these samples

and comparing to other datasets. For this purpose the building area was defined as the

LEED Certification

Certified Gold Silver Total

SCL 2 2 4 8

Washington 3 4 5 12

Region 3 10 10 23

16

conditioned, enclosed area of the building. In the case of “warehouse” use, the area used

generally included all the storage area that was generally “semi heated” but included lights and

other equipment. In all other building types the areas of parking garages, outdoor sales areas,

outdoor parking areas and unconditioned mechanical penthouses or similar spaces were not

included in the building areas used in calculating the EUIs. This definition was used by the

CBECS authors and the CBSA data was adjusted to be consistent with this approach.

Table 4.1 shows the relationships between EUIs observed in the Seattle buildings and the EUIs

observed in similar buildings in the state and regional samples. These comparison values are

calculated with the building area as the only weighting. The case weighting was abandoned

when EUIs could not be developed on a large portion of the sample. Only the total line preserves

the original weighting in the hope of reducing the bias in such a calculation. Table 4.2 uses the

same data but recalculates data into kWh/ sq. ft.

Table 4.1: Total EUI summary (kBtu/sq. ft.)

Building Type Seattle Washington Region

Mean SD Obs. Mean SD Obs. Mean SD Obs.

Assembly 68.6 1.0 2 64.1 15.0 4 83.1 37.1 7

Education 45.4 16.8 4 72.3 17.6 15 61.4 18.2 34

Health Services 98.4 7.3 2 119.9 27.3 6 111.8 35.3 10

Hospital 249.2 2.4 2 184.5 34.9 6 193.5 46.6 10

Institution 69.3 19.9 4 71.6 20.7 11 75.2 29.7 20

Office 59.9 15.5 2 60.2 12.4 4 71.7 26.1 19

Retail 112.7 36.9 5 111.1 33.8 17 95.5 34.9 40

Warehouse 84.1 0.0 1 88.8 55.1 12 70.5 58.1 25

Total 84.1 41.8 22 87.0 46.8 75 77.8 43.0 165

Table 4.2: Total EUI summary (kWh/sq. ft.)

Building Type Seattle Washington Region

Mean SD Obs. Mean SD Obs. Mean SD Obs.

Assembly 20.1 0.3 2 18.8 4.4 4 24.3 10.9 7

Education 13.3 4.9 4 21.2 5.2 15 18.0 5.3 34

Health Services 28.8 2.1 2 35.1 8.0 6 32.8 10.4 10

Hospital 73.0 0.7 2 54.1 10.2 6 56.7 13.7 10

Institution 20.3 5.8 4 21.0 6.1 11 22.0 8.7 20

Office 17.6 4.6 2 17.6 3.6 4 21.0 7.7 19

Retail 33.0 10.8 5 32.5 9.9 17 28.0 10.2 40

Warehouse 24.6 0.0 1 26.0 16.2 12 20.7 17.0 25

Total 24.6 12.2 22 26.0 12.5 75 22.4 14.2 165

17

Table 4.3 shows the electric only EUIs for the samples. These values are summarized from the

billing information provided by the various utilities and reflect the electric use independent of

heating type, or other factors.

Table 4.3: Electric Only EUI summary (kWh/sq. ft.)

Building Type Seattle Washington Region

Mean SD Obs. Mean SD Obs. Mean SD Obs.

Assembly 7.6 0.4 2 7.2 1.7 4 13.3 6.8 7

Education 10.1 11.4 4 10.9 4.2 15 9.6 3.5 34

Health Services 12.9 0.0 1 14.9 6.2 5 14.3 6.6 9

Hospital 37.2 9.2 2 25.1 8.2 6 25.3 8.4 10

Institution 15.2 3.0 4 14.9 3.0 11 15.4 3.7 20

Office 15.7 1.7 2 15.8 1.5 4 17.8 7.0 19

Retail 23.6 5.9 5 24.6 5.8 17 21.6 6.0 40

Warehouse 19.5 0.0 1 19.8 11.6 12 15.1 11.7 25

Total 18.2 7.9 21 18.5 9.4 74 16.5 9.0 164

Table 4.4 shows the comparable EUIs from the Commercial Building Stock Assessment (CBSA)

sample (Kema-Xenergy 2003) and the Commercial Building Energy Consumption Survey

(CBECS) sample (EIA 2003) in kBtu for all energy sources used in the buildings. The CBSA is

a regional summary based on audits conducted on new building stocks from 1990 to 2000 soon

after they were constructed. The regional sample is restricted to buildings of the same type as

the SCL sample for which data was available. Weighting is compiled by building type and not

designed to summarize across building types to the entire commercial sector. The CBECS

summaries give an indication of the scale of the EUIs observed in the SCL sample, however, it is

included here as the standard table used to assess energy performance in various programs

including LEED and the “2030 Challenge.”

Table 4.4: Adjusted EUIs from CBSA Regional Study (1990-2000 Cohorts) and CBECS

Building Type SCL CBSA CBECS

Mean Mean Std. Dev. N Post 1990 All

Assembly 68.6 — — — 81.5 68.7

Education 43.5 83.8 73.7 7 80.6 83.1

Health Services 98.2 76.5 48.4 8 84.4 94.6

Hospital 250.1 — — — — 249.2

Institution 69.3 — — — 119.7 115.8

Office 59.4 81.8 46.7 46 88.0 92.9

Retail 112.7 139.0 71.6 32 94.4 91.3

Warehouse 84.1 83.0 46.2 11 33.3 45.2

18

In this relatively small sample, the EUI comparisons between the regional sample and the Seattle

buildings suggest that the energy use in these two sets are comparable. Indeed, within the

precision of the sample size and standard there is only limited statistically significant differences

between these two datasets:

Especially when compared to the older regional sample and the CBECS sample the education

sector sample in Seattle has significant savings. This difference is less significant when

comparing to the regional or state 2002-2004 sample, although there is still some noticeable

difference.

In the office sector, two large buildings with large and active server loads were not included

in the summary of the regional samples. Had these buildings been included, the office sector

EUI would have increased over 40% and the difference between the Seattle buildings and the

regional or state sample would have been significant. We elected to remove these two

buildings because with such small samples very small sample differences can result in

unrealistic comparisons. In this case, the server loads were not atypical of some Seattle

buildings, but no such buildings appeared in the Seattle sample.

The retail sector is compromised by the integration of grocery stores into more traditional

“big box” stores. The grocery application adds a substantial refrigeration and heating load to

those buildings. Even in very large stores this combination increases the EUI by 70 to

100 percent. As a result, the EUIs calculated for any particular retail sample is largely

determined by the fraction of grocery application which incidentally occurs within the stores

in the sample.

5. Interviews with Architects and Designers Interviews were conducted with the architects and engineers involved in the design of the

buildings surveyed.

The goals of the interviews were to:

Understand what energy codes were used and how they were enforced.

Learn about current trends in attitudes toward energy efficiency/energy codes.

Determine the importance of energy efficiency in the design process.

The interviews focused on the decision-making process in the individual building projects.

Because of the time between the planning phases of these projects and the actual interviews

(typically at least five years or longer) the interviews tended to focus more on current attitudes

toward energy efficiency and energy codes and less on the decisions made specifically for

buildings in this study.

In this section, the responses from the individual utility territories are compared to the responses

from the rest of the regional survey. While the main study compares the results in this survey to

previous interview results in the regional survey done in 1999, for this summary the data was not

available to make such comparisons in individual service territories. Thus in these summaries

comparisons are made with the regional results.

19

Auditors also performed on-site interviews with building operators and site managers. These

interviews sometimes supplemented, or were comparable to, the interviews with designers but

the time span between the design phase of these projects and the designer interviews limited the

utility of such comparisons.

5.1. Interview Sample

Table 5.1 shows the distribution of the interviews conducted in the Seattle City Light service

territory and how this compares with the rest of the regional survey.

Table 5.1: Interview Sample Distribution by Design Role

Design Role SCL Washington Region

N % N % N %

Architect / Envelope

Designer 11 52 37 51 83 55

Mechanical Engineer 9 43 33 45 58 38

Mechanical Contractor 0 0 0 4 3

Other 1 5 3 4 6 4

Total 21 100 73 100 151 100

5.2. Energy Codes

As with previous studies, interviews tried to gauge the attitude and acceptance of the energy

codes. While there were complaints, the level of acceptance in these types of surveys has

increased over the last two decades. In some cases, architects even suggested that the code

be made even more stringent.

Interviewees were asked if there were any elements of the energy code they considered to be

poorly thought-out or not cost-effective. The results are presented in Table 5.2. Only about

60% of the interviewees answered this question with the majority arguing that the codes were

too strict. This was less true in jurisdiction with little or no enforcement. The Seattle code is

among the strictest and most heavily enforced codes in the nation. This level of enforcement

is illustrated by the amount of feedback that designers received (Table 5.3).

Table 5.2: Reactions to Energy Code Provisions

Code Problems SCL Washington Region

N % N % N %

Too Strict 11 58 28 58 43 44

Too Lenient 1 5 1 2 7 7

Poor Wording 2 11 7 15 16 16

Internal Conflicts 3 19 7 15 15 15

Not Enforced 0 0 2 4 3 3

Flexible 0 0 0 0 1 1

Good Code 0 0 0 0 2 2

Deficient Coverage 1 5 3 6 11 11

Total 19 100 48 100 98 100

20

Table 5.3: Plan Reviewer or Building Official Feedback (%)

Feedback after Plan

Examination SCL Washington Region

Yes 57 52 46

No 38 41 51

Don’t Remember 5 7 3

The majority of respondents said they design their buildings in accordance with the relevant

energy code. Respondents also indicated that they sometimes worked to exceed minimum

lighting, HVAC, and envelope requirements.

Table 5.4 shows that many designers assert that they often exceed code requirements in some

components. In Seattle, the designers seemed to be convinced that they often exceeded the

code requirements.

Table 5.4: Percent of Respondents Claiming “Beyond Code” in their Designs

Component SCL Washington

Regional

Total

% % %

Lighting 45 38 37

HVAC 41 36 49

Envelope 64 44 40

5.3. Attitudes Toward Energy Efficiency

Interviewees were questioned about how important incorporating energy efficient features

were to members of the design team. Table 5.5 shows that about half of the regional sample

identified energy efficiency as an important factor. The Seattle area largely mimicked the

region as a whole and represented some increase over the rest of the Washington sample.

Table 5.5: Importance of Energy Efficiency to the Design Team (%)

Level of

Importance SCL Washington Region

Not at all 18 26 48

Moderate 23 30 37

Very 59 44 56

The interviews assessed how energy efficiency decisions are made and if design practices

have changed since the 1999 interviews. Individual design professionals still make the

majority of energy efficiency decisions; however, team decision making is becoming more

prevalent and design professionals are changing their practices to reflect a growing client

demand for energy efficiency.

Table 5.6 illustrates the responses to questions about the use of LEED in the design process.

In general substantial interest was shown in the LEED process and LEED certification.

21

However, outside of Seattle this interest did not result in much client interest. By the end of

the time the projects were completed only a small number had actually pursued LEED

certification. Of all the areas in the regional survey, Seattle City Light had the largest

number of LEED buildings implemented after the initial interest. It should be pointed out

that the LEED program was only just starting when buildings in this sample were in planning

stages. Later the support of various utility and state agencies might close the apparent

difference between Seattle and the rest of the region.

Table 5.6: LEED® Requested by Clients

LEED Requested

in SCL

LEED Included

in SCL

LEED Requested

in Washington

LEED Requested

in Region

LEED Included

in Region

% % % % %

Yes 36 32 6 8 5

No 64 68 94 92 95

N/A 0 0 3 1 1

N 31 22 73 150 150

Interviewees were asked to suggest the best opportunities to promote energy efficiency.

Table 5.7 presents the set of responses to this request. Respondents indicated that the best

way to promote energy efficiency is to provide more education on life-cycle costs and on

potential energy efficiency options. In many cases throughout this review it was apparent

that the distinction between the goals of the energy efficiency and the implementation of that

efficiency is disconnected. It appears from our interview respondents that at least this group

felt the utility of education would be helpful. Developing case studies showing real world

buildings and their energy use was the most common educational tool mentioned. Providing

more financial incentives in the form of either utility rebates/incentives or tax credits was

another way of supporting energy efficiency mentioned.

Table 5.7: Opportunities to Promote Energy Efficiency

Best Opportunities SCL Washington Region

N % N % N %

Education 15 56 51 61 106 63

Financial Incentives 5 18 11 13 25 15

Stronger code 4 15 8 10 12 7

Increase Energy Costs 0 0 5 6 8 5

Technology Changes 2 7 5 6 7 4

Keep-up with the Jones

Marketing 1 4 1 1 5 3

LEED® 0 0 1 1 4 2

Enforce code 0 0 2 2 2 1

Total 27 100 84 100 169 100

22

6. Overall Observations The sample and buildings reviewed in this survey were designed to represent the Seattle building

stock separately. As such the comparison to the regional samples reflect both the differences in

the attitudes and design approaches used in this locality and the different building types

reflective of a built-up urban area.

Building Size and Type. As with any sample some of the nature of comparison is

influenced by the buildings that happened to be built in the city in the construction

window used to constrain the sample. This process is further influenced by the level of

participation from the building operators and owners in the audits and billing analysis.

For this sample, the buildings in the SCL sample were 25% larger than comparable

buildings in the regional sample. This difference vanishes when buildings are compared

to other urbanized areas throughout the region.

Envelope Characteristics. The most striking features of the Seattle buildings is a large

amount of glazing in the large Seattle buildings. This is partly the result of building size,

but even with that taken into account the sample has about 46% more glazing area as a

percent of wall area than the regional sample (see Table 3.12). Indeed this spread is

apparent (or even greater) when the data is subdivided into separate states or utility

regions. It does appear that the trend toward greater glazing area is balanced by a trend

toward higher performance glass and higher performance in other building components.

This combination results in a 22% reduction in building heat loss rates in Seattle

compared to the regional heat loss rates (see bottom row of Table 3.11).

HVAC Characteristics. The nature of the Seattle building population seems to result in

more complex and more controlled HVAC systems than the region as a whole. The

incidence of built-up VAV systems (particularly with electric reheat) was almost 30%

higher in Seattle than the regional sample as a whole. Conversely, the use of

single-zone-Dx systems was only about 60% as likely as the regional sample as a whole.

The more complex HVAC systems were a focus of the utility incentive programs and

several innovative HVAC system designs were observed in this service territory. For the

simple, single-zone, HVAC systems the efficiency and controls were more typical of

building observed throughout the region.

Lighting Characteristics. The actual average LPD in the entire Seattle sample was 1.14

Watts/sq. ft.., or 13% lower than the average Seattle Energy Code LPD of 1.31 across

building types combined (see Table 3.3 and Table 3.4). However, the lighting systems in

the SCL sample as a whole were similar to the region and state samples. In most building

types the distinctions in actual average LPDs between any of these samples was minor.

One exception to this was the SCL sample of offices. In this case, the LPDs of the Seattle

sample of office buildings were almost 30% less than the regional sample as a whole. The

average LPD in the Seattle office buildings was 0.74 Watts/sq. ft., or 22% more efficient

than the Seattle Energy Code requirement of 0.95 in office buildings. And although not

statistically significant, the LPD in Seattle’s institutional buildings, residential/lodging,

and retail buildings were slightly lower than in the regional sample (see Table 3.3).

23

Similarly, lighting controls were in use much more often in the SCL sample. Daylighting

controls, for example were more than twice as likely to be used in the Seattle buildings

than in the state sample, and over three times as likely than in the regional sample (see

Table 3.2). This was partly due to the use of daylighting as part of the LEED program,

which was supported by the utility and has become quite popular in this area. This seems

to represent a significant difference with the rest of the regional sample.

Overall Energy Use. The EUIs of the Seattle buildings were not generally much different

than comparable building types in the region as a whole. It appears, however, that when

compared to the CBECS national benchmarks the SCL sample does have significantly

lower EUIs in at least some building types. Since this comparison was made with a large

number of buildings built throughout the country after 1990, the improvements are not

surprising. When compared to the Post-1990 cohort in the CBSA data there are

differences in some building types, but the small sample sizes tend to reduce the utility of

these comparisons.

Code Compliance and Designer Interviews. On the whole, the level of code compliance

in Seattle is comparable to the other sample throughout the region. In the case of Seattle,

the energy code is generally more stringent and more enforced than in most other areas of

the region. Nevertheless, the level of code compliance is comparable. There were some

differences in individual building components:

Lighting Code compliance. The actual lighting efficiency in the Seattle sample was

89% in compliance with the Seattle Energy Code (SEC). This is 1l% more compliant

than the level of compliance in the Washington and regional samples (see Table 3.5).

HVAC Code Compliance. The compliance with equipment efficiency standards in

the Seattle sample was about 82% for cooling equipment and 99% for heating

equipment. This compares to about 87% for cooling equipment and 98% for heating

equipment in the region as a whole.

Envelope Code compliance. The level of envelope code compliance is mixed. For

the 2001 code, the Seattle sample buildings were 90% compliant, slightly lower that

the 94% compliance in the Washington sample (excluding Seattle).

Designer Attitudes. A more striking finding came from the interviews conducted

with the architects and engineers involved in the SCL sample. This group was more

interested and more willing to develop building designs that “exceeded” code

requirements. About 20% more respondents asserted that they attempted to exceed the

code in the buildings and systems they designed. For the most part, this group seems

to welcome the Seattle energy code and be willing to comply with it or with a more

stringent code.

Much of the differences observed in the SCL sample could be traced to the participation and use

of the LEED certification system as a basis for marketing and assessing energy efficiency. The

24

assessment of that program in the SCL service territory is included in a separate document. For

the overall SCL sample, the impact of the LEED buildings is not particularly striking. While

many of the more advanced control and HVAC systems are associated with those buildings,

overall performance does not seem to be much improved at least within the statistical limitations

of this small sample. In many cases, the architectural or programmatic needs of the building

dominate the overall performance and the nuances brought by the sustainable design goals are

relatively less significant.

From the point of view of the architects and other professional interviewed, there seemed to be

an expanded interest in energy efficiency. There were numerous comments along the line that

education and direction from the utility would be well received. From this review it would

appear that such input is also necessary.

7. References

Baylon, David, and Mike Kennedy. 2008. Baseline Characteristics of the 2002-2004

Nonresidential Sector: Idaho, Montana, Oregon, and Washington. Portland, Oregon:

Northwest Energy Efficiency Alliance.

Baylon, David, 2008, Comparison of LEED buildings in the Seattle City Light Service Area and

the 2004-2004 Pacific Northwest Commercial Building Stock, Seattle City Light, Seattle

Washington,

Baylon, David, Mike Kennedy, and Shelley Borelli. 2001. Baseline Characteristics of the

Nonresidential Sector: Idaho, Montana, Oregon, and Washington. Portland, Oregon:

Northwest Energy Efficiency Alliance.

Baylon, David, and David Robison. 2008. Baseline Energy Use Intensities of the 2002-2004

Nonresidential Sector: Idaho, Montana, Oregon, and Washington. Portland, Oregon:

Northwest Energy Efficiency Alliance.

Baylon, David, and Poppy Storm. 2008. Comparison of Commercial LEED Buildings and

Non-LEED Buildings within the 2002-2004 Pacific Northwest Commercial Building Stock.

Proceedings of the 2008 ACEEE Summer Study. Washington DC: ACEEE.

Energy Information Administration. 2003. Commercial Buildings Energy Consumption Survey

(CBECS). http://www.eia.doe.gov/emeu/cbecs/

Kema-Xenergy, Inc. 2004. Assessment of the Commercial Building Stock in the Pacific

Northwest (CBSA). Portland, Oregon: Northwest Energy Efficiency Alliance.