7-A-i 

APPENDIX 7-A. RECS 2005 VARIABLES AND VALUES

TABLE OF CONTENTS

7-A.1 INTRODUCTION ................................................................................................. 7-A-1

7-A.2 SAMPLE DETERMINATION .............................................................................. 7-A-1

7-A.2.1 Clothes Dryers ..................................................................................... 7-A-1

7-A.2.2 Room Air Conditioners ........................................................................ 7-A-2

7-A.3 RECS 2005 DATABASE VARIABLE RESPONSE CODES .............................. 7-A-4

LIST OF TABLES

Table 7-A.2.1 Selection of RECS 2005 Records for Clothes Dryers ............................... 7-A-1

Table 7-A.2.2 RECS 2005 Variables Used for Clothes Dryers ........................................ 7-A-2

Table 7-A.2.3 Energy Star Sizing Guidelines for Room Air Conditioners ....................... 7-A-3

Table 7-A.2.4 Selection of RECS 2005 Records for Room Air Conditioners .................. 7-A-3

Table 7-A.2.5 RECS 2005 Variables Used for Room Air Conditioners........................... 7-A-4

Table 7-A.3.1 RECS 2005 Variable Response Codes ...................................................... 7-A-5
7-A-1 

APPENDIX 7-A. RECS 2005 VARIABLES AND VALUES

7-A.1 INTRODUCTION

The U.S. Department of Energy (DOE) created a database containing a subset of the 

records and variables from DOE’s Energy Information Administration (EIA)’s RECS 2005.1

DOE used this RECS subset in the life-cycle cost (LCC) analysis of the Room Air Conditioners 

and Clothes Dryers Rulemaking. This appendix explains the variable name abbreviations and 

provides definitions of the variable values. For the entire RECS 2005 dataset, refer to 

http://www.eia.doe.gov/emeu/recs/recspubuse05/pubuse05.html. 

7-A.2 SAMPLE DETERMINATION

7-A.2.1 Clothes Dryers 

 The subset of RECS households used for clothes dryers met all of the following criteria: 

• The household had a clothes dryer. 

• The household had and used a clothes washer. 

• Clothes dryer fuel was electricity, natural gas, or LPG.

• Clothes dryer use was greater than zero. 

 The RECS 2005 variables used to match the selection criteria are listed in Table 7-A.2.1. 

Table 7-A.2.1 Selection of RECS 2005 Records for Clothes Dryers 

Product Class Selection Criterion # of 

Records

# of US Households 

Represented (million)

Electric

WASHLOAD ≠ 9

DRYRFUEL = 5

DRYRUSE > 0

2655 67.0 

Gas

WASHLOAD ≠ 9

DRYRFUEL = 1 OR 2

DRYRUSE > 0

756 20.3 

Electric 

Ventless

WASHLOAD ≠ 9

DRYRFUEL = 5

DRYRUSE > 0 

Type of Housing = Mobile home, 

multifamily, or single family (≤1000 sq. 

ft., no attached garage, no basement)

570 14.3 
7-A-2 

Table 7-A.2.2 RECS 2005 Variables Used for Clothes Dryers 

Variable Description

Location Variables

REGIONC Census region

DIVISION Census division

DIVISION + LRG STATE* Combined large state (LRGSTATE) and census division (DIVISION) 

Household Characteristics Variables 

DOEID DOE 4-digit identification number

NWEIGHT Final weight

YEARMADE Year residence built

WASHLOAD Average number of wash loads per week in household clothes washer

DRYRUSE Clothes dryer usage frequency

BTUELCDR Electricity used for drying clothes

DRYRFUEL Clothes dryer fuel

BTUNGAPL Natural gas appliance use

BTULPAPL LPG appliance use 

TYPEHUQ Type of housing unit 

TOTSQFT Household square footage

CELLAR Household has a basement

PRKGPLC1 Household has attached garage

* Not part of RECS 2005 variables.

7-A.2.2 Room Air Conditioners

 The subset of RECS 2005 records used for room air conditioners in this analysis met all 

of the following criteria: 

 

• A room air conditioner was present in the household. 

• Room air conditioner energy consumption was greater than zero. 

To divide the subset of RECS records into the appropriate product classes, DOE used Energy 

Star sizing guidelines for room air conditioners2 as shown in Table 7-A.2.3 and the cooling 

square footage area from RECS 2005 for each household. For households with multiple air 

conditioners, DOE divided the square footage by the number of room air conditioners to derive 

the average cooling square footage area per room air conditioner. DOE made adjustments to the 
7-A-3 

guidelines for records where more than two people lived in the household. For each of these 

households this resulted in adding 600 Btu/h to the capacity needed for each additional person. 

The RECS 2005 variables used to match the selection criteria are listed in Table 7-A.2.4. DOE 

used the same RECS 2005 subset to characterize both product classes 3 and 8. 

Table 7-A.2.3 Energy Star Sizing Guidelines for Room Air Conditioners

Area to be cooled Capacity Needed (BTUs per hour) Room Air Conditioner product 

class Assignment

100–150 5,000 <6,000 Btu/h with louvers

150–250 6,000

250–350 7,000

8,000–13,999 Btu/h with louvers

and without louvers

300–350 8,000

350–400 9,000

400–450 10,000

450–550 12,000

550–700 14,000

700–1,000 18,000

≥ 20,000 Btu/h with louvers

1,000–1,200 21,000

1,200–1,400 23,000

1,400–1,500 24,000

1,500–2,0000 30,000

2,000–2,500 34,000

Table 7-A.2.4 Selection of RECS 2005 Records for Room Air Conditioners

Product Class Selection Criterion # of 

Records

# of US Households 

Represented 

(million)

# of Room AC Units 

Represented 

(million)

1 

COOLTYPE = 2

USEWWAC ≠ 0

Average adjusted capacity ≤ 6,000 Btu/h

266 9.2 16.9

3 and 8

COOLTYPE = 2

USEWWAC ≠ 0

Average adjusted capacity > 6,000 Btu/h 

and ≤ 14,000 Btu/h

890 38.9 97.1

5 

COOLTYPE = 2

USEWWAC ≠ 0

Average adjusted capacity ≥ 18,000 Btu/h

66 2.5 5.4
7-A-4 

Table 7-A.2.5 RECS 2005 Variables Used for Room Air Conditioners 

Variable Description

Location Variables

DIVISION Census division

DIVISION + LRG STATE* Combined large state (LRGSTATE) and census division (DIVISION) 

CD65 Cooling degree-days to base 65, 1-04 TO 12-04 

Household Characteristics Variables 

DOEID DOE 4-digit identification number

NWEIGHT Final weight

TYPEHUQ Type of housing unit 

COOLTYPE Type of air conditioning equipment

ACHOUSE Central AC cooling usage 

ACROOMS Number of rooms cooled by central AC during the summer 

NUMBERAC Number of window or wall air conditioning units 

WWACAGE Approximate age of window or wall air conditioning unit 

USEWWAC Usage description for most-used window or wall air conditioner 

TOTCSQFT Household square footage

BTUELCOL Electricity used for household cooling 

LocationID* Not part of RECS, added to link to weather data (See App. 7-E) 

* Not part of RECS 2005 variables.

7-A.3 RECS 2005 DATABASE VARIABLE RESPONSE CODES

Table 7-A.3.1 provides the response codes for all RECS 2005 variables used in the Room 

Air Conditioner and Clothes Dryer samples.
7-A-5 

Table 7-A.3.1 RECS 2005 Variable Response Codes 

Variable Definition

Common Variables (Alphabetical)

CDD65 Cooling degree-days to base 65, 1-04 TO 12-04

DIVISION Census division

 1 = New England 

2 = Middle Atlantic

 3 = East North Central 

4 = West North Central

 5 = South Atlantic 

 6 = East South Central 

 7 = West South Central

 8 = Mountain 

9 = Pacific

DIVISION + LRG STATE* Combined large state (LRGSTATE) and census division (DIVISION)

 1 = New England 

 2 = Middle Atlantic (not including New York) 

 3 = East North Central 

4 = West North Central

 5 = South Atlantic (not including Florida) 

 6 = East South Central 

 7 = West South Central (not including Texas) 

 8 = Mountain 

9 = Pacific (not including California)

10 = New York

 11 = California 

13 = Texas

 14 = Florida 

DOEID DOE 4-digit identification number

LRGSTATE Large state designation

 0 = Other 

1 = New York

2 = California

3 = Texas

4 = Florida

NHSLDMEM Number that live in household 

NWEIGHT Final weight

REGIONC Census region

 1 = Northeast 

2 = Midwest

 3 = South 

4 = West

TOTSQFT Household square footage

TYPEHUQ Type of housing unit

 1 = Mobile Home 

 2 = Single-family detached

 3 = Single-family attached

 4 = Apartment building with 2-4 units 

5 = Apartment building with 5 or more units
7-A-6 

YEARMADE Year home built 

1 = Before 1940

2 = 1940-49

 3 = 1950-59

4 = 1960-69

5 = 1970-79

6 = 1980-84 

7 = 1985-89

8 = 1990-94

9 = 1995-99

 10 = 2000-2002 

 11 = 2003 

 12 = 2004 

13 = 2005

Sample Variables (Alphabetical)

ACHOUSE Central AC cooling usage

 1 = All of the rooms 

 2 = Only some of the rooms 

0 = None of the rooms cooled

ACROOMS Number of rooms cooled by central AC during the summer

ADQINSUL Home/Apartment insulation

1 = Well insulated

2 = Adequately insulated

 3 = Poorly insulated 

4 = No insulation

AGECENAC Central air conditioning equipment age

1 = Less than 2 years old

 2 = 2 to 4 years old 

3 = 5 to 9 years old

4 = 10 to 19 years old

 5 = 20 years or older 

 6 = As old as the home 

ATTCCOOL How much of attic air-conditioned during summer months?

1 = All

2 = Part

3 = None

BASECOOL How much of basement air-conditioned during summer months?

1 = All

2 = Part

3 = None

BEDROOMS Number of bedrooms in the home

BTUELCDR Electricity clothes dryer use estimated (thousands of BTU) 

9999999=Not Applicable

BTUELCOL Electricity cooling use estimated (thousands of BTU) 

9999999=Not Applicable

BTULPAPL LPG appliance use estimated (thousands of BTU) 

9999999=Not Applicable

BTUNGAPL Natural gas appliance use estimated (thousands of BTU) 

9999999=Not Applicable
7-A-7 

CATHCEIL Any cathedral ceilings in the home/apartment?

1 = Yes

2 = No

CELLAR Household has a basement

1 = Yes

0 = No

9 = Skip

CENACHP Is your central air-conditioning system a heat pump?

1 = Yes

0 = No

COOLTYPE Type of air conditioning equipment

1 = Central system

 2 = Individual units in the windows or wall 

 3 = Both central and individual units 

DRYRFUEL Clothes dryer fuel

 1 = Natural gas from underground pipes 

 2 = Bottled Gas (LPG or Propane) 

5 = Electricity

99 = No Answer/Not Applicable

DRYRUSE Clothes dryer usage frequency

1 = Use it every time you wash clothes

 2 = Use it for some, but not all, loads of wash 

3 = Use it infrequently

ESWWAC Energy Star AC unit?

1 = Yes

0 = No

FINATTRMS Number of finished rooms in the attic

FINBASERMS Number of finished rooms in the basement

GARGCOOL Garage air-conditioned during the summer months?

1 = Yes

0 = No

HIGHCEIL Unusually high ceilings in home?

1 = Yes

0 = No

LocationID* Not part of RECS, added to link to weather data (See App. 7-E)

NUMBERAC Number of window or wall air conditioning units

PRKCPLC1 Household has attached garage

0 = No 

1 = Yes

TREESHAD Home shaded by trees from afternoon summer sun?

1 = Yes

0 = No

TOTATTCSQFT Square footage of attic

TOTBASESQFT Square footage of basement

TOTGARGSQFT Square footage of garage
7-A-8 

TYPEGLASS Type of glass in windows in home/apartment

 1 = Single-pane glass

 2 = Double-pane glass

 3 = Double-pane glass with Low-e coating

4 = Triple-pane glass

5 = Triple-pane glass with Low-e coating

USECENAC Central AC usage during summer

 0 = Not used at all 

 1 = Turned on only a few days or nights when really needed 

2 = Turned on quite a bit

3 = Turned on just about all summer

USEWWAC Usage description for most-used window or wall air conditioner

 0 = Not used at all 

 1 = Turned on only a few days or nights when really needed 

2 = Turned on quite a bit

3 = Turned on just about all summer

WASHLOAD Average number of wash loads per week in household clothes washer

 1 = 1 load or less each week

 2 = 2 to 4 loads 

3 = 5 to 9 loads

 4 = 10 to 15 loads 

5 = More than 15 loads

WINDOWS Approximate number of windows (not including unheated areas)

 10 = 1 or 2 

 20 = 3 to 5 

30 = 6 to 9

 41 = 10 to 15 

42 = 16 to 19

50 = 20 to 29

 60 = 30 or more 

00 = None

WWACAGE Approximate age of window or wall air conditioning unit

1 = Less than 2 years old

 2 = 2 to 4 years old 

3 = 5 to 9 years old

4 = 10 to 19 years old

 5 = 20 years or older 

 6 = As old as the home (if volunteered) 

* Not part of RECS 2005 variables.
7-A-9

REFERENCES

1. U.S. Department of Energy - Energy Information Administration, Residential Energy 

Consumption Survey: 2005 Public Use Data Files, 2005.

<http://www.eia.doe.gov/emeu/recs/recspubuse05/pubuse05.html>

2. Energy Star, Properly Sized Room Air Conditioners.

<http://www.energystar.gov/index.cfm?c=roomac.pr_properly_sized>