Table HC9.4 Space Heating Characteristics by Climate Zone, 2005

 Million U.S. Housing Units

Total......................................................................... 111.1 10.9 26.1 27.3 24.0 22.8

Do Not Have Space Heating Equipment................ 1.2 Q Q N 0.3 0.8

Have Main Space Heating Equipment.................... 109.8 10.9 26.0 27.3 23.7 22.0

Use Main Space Heating Equipment..................... 109.1 10.9 26.0 27.3 23.2 21.7

Have Equipment But Do Not Use It........................ 0.8 N N Q 0.5 Q

Main Heating Fuel and Equipment

Natural Gas........................................................... 58.2 6.2 17.6 14.9 12.6 6.9

Central Warm-Air Furnace................................. 44.7 5.0 13.4 11.0 9.8 5.5

For One Housing Unit..................................... 42.9 4.9 12.4 10.5 9.7 5.4

For Two Housing Units................................... 1.8 Q 0.9 0.5 Q Q

Steam or Hot Water System.............................. 8.2 1.0 3.3 3.3 0.3 Q

For One Housing Unit..................................... 5.1 0.7 2.3 1.9 Q Q

For Two Housing Units................................... 3.1 0.3 1.0 1.4 Q Q

Floor, Wall or Pipeless Furnace......................... 2.3 Q 0.6 0.3 1.4 Q

Room Heater...................................................... 2.0 Q Q Q 0.8 0.8

Other Equipment................................................ 0.9 Q 0.2 Q 0.3 0.3

Electricity............................................................... 33.7 1.0 3.3 7.1 8.1 14.1

Built-in Electric Units.......................................... 5.0 0.6 1.1 2.0 0.9 0.4

Central Warm-Air Furnace................................. 16.0 0.3 1.3 2.0 4.7 7.6

For One Housing Unit..................................... 15.2 0.3 1.2 2.0 4.6 7.1

For Two Housing Units................................... 0.9 N Q Q Q 0.5

Heat Pump......................................................... 9.2 Q 0.4 2.7 1.8 4.2

Portable Electric Heater..................................... 1.6 N Q Q 0.6 0.7

Other Equipment................................................ 1.9 Q 0.4 Q Q 1.2

Fuel Oil.................................................................. 7.7 1.5 2.9 3.1 Q N

Steam or Hot Water System.............................. 4.7 0.8 1.7 2.1 Q N

For One Housing Unit..................................... 3.3 Q 1.5 1.2 N N

For Two Housing Units................................... 1.4 Q 0.3 0.9 Q N

Central Warm-Air Furnace................................. 2.8 0.7 1.1 0.9 Q N

Other Equipment................................................ 0.3 Q Q Q Q N

Wood..................................................................... 2.9 0.7 0.4 0.8 0.6 0.4

Heating Stove.................................................... 2.0 0.4 0.3 0.6 0.5 Q

Other Equipment................................................ 0.9 Q Q Q Q Q

Propane/LPG......................................................... 6.0 1.3 1.2 1.0 1.9 0.6

Central Warm-Air Furnace................................. 4.1 1.0 1.0 0.8 1.1 0.2

Room Heater...................................................... 0.9 Q Q Q 0.4 Q

Other Equipment................................................ 1.0 0.3 Q Q 0.4 Q

Kerosene............................................................... 0.7 Q Q Q Q Q

Other Fuel.............................................................. 0.6 Q Q Q Q N

Housing Units Served by

Main Heating Equipment

One Housing Unit.................................................. 101.0 10.2 23.1 23.6 23.0 21.0

Two or More Housing Units.................................... 8.8 0.7 2.9 3.7 0.7 1.0

Do Not Have Heating Equipment........................... 1.2 Q Q N 0.3 0.8

Climate Zone1

Space Heating Characteristics

2,000 CDD 

or More

and Less 

than 4,000 

HDD

Less than 2,000 CDD and --

Less than 

4,000 HDD

Greater than 

7,000 HDD

5,500 to 

7,000 HDD

4,000 to 

5,499 HDD

Housing 

Units 

(millions)

Energy Information Administration

2005 Residential Energy Consumption Survey: Preliminary Housing Characteristics Tables
Table HC9.4 Space Heating Characteristics by Climate Zone, 2005

 Million U.S. Housing Units

Climate Zone1

Space Heating Characteristics

2,000 CDD 

or More

and Less 

than 4,000 

HDD

Less than 2,000 CDD and --

Less than 

4,000 HDD

Greater than 

7,000 HDD

5,500 to 

7,000 HDD

4,000 to 

5,499 HDD

Housing 

Units 

(millions)

Age of Main Heating Equipment

Used by One Housing Unit

Less than 2 Years.............................................. 11.7 1.1 2.5 2.5 2.7 2.8

2 to 4 Years....................................................... 13.8 1.4 2.9 2.6 3.0 3.9

5 to 9 Years....................................................... 20.6 2.2 4.4 4.5 4.6 4.9

10 to 19 Years.................................................... 24.8 3.2 5.2 6.0 5.6 4.7

20 Years or More............................................... 21.5 1.9 5.5 5.6 5.4 3.2

Don't Know......................................................... 8.6 0.5 2.6 2.4 1.7 1.5

Used by Two or More Housing Units

Less than 2 Years.............................................. 0.3 Q Q Q Q Q

2 to 4 Years....................................................... 0.4 Q Q Q Q Q

5 to 9 Years....................................................... 0.6 Q Q Q Q Q

10 to 19 Years.................................................... 1.1 Q 0.3 0.4 Q Q

20 Years or More............................................... 2.7 Q 0.7 1.2 0.3 0.3

Don't Know......................................................... 3.7 0.3 1.3 1.7 Q Q

Proportion of Heat Provided by

Main Heating Equipment

All or Almost All..................................................... 98.9 9.6 23.7 24.8 20.5 20.5

Do Not Use Main Heating Equipment.................... 5.8 0.9 1.3 1.4 1.5 0.8

About Three-Fourths.............................................. 4.3 0.5 1.1 1.1 1.2 0.5

Closer to One-Half................................................. 2.0 Q Q Q 0.8 1.0

Secondary Heating Fuel and Equipment

No.......................................................................... 76.2 6.4 18.1 18.6 15.2 17.9

Yes (More than One May Apply) 34.9 4.6 8.0 8.7 8.8 4.9

Natural Gas........................................................ 5.0 0.8 1.2 0.9 1.5 0.6

Fireplace........................................................ 2.7 0.5 0.7 0.4 0.8 0.3

Room Heater.................................................. 0.5 Q Q Q Q Q

Central Warm-Air Furnace.............................. 1.1 Q Q 0.3 0.4 Q

Other Equipment............................................ 0.8 Q Q Q Q Q

Electricity........................................................... 19.7 1.8 4.6 5.3 5.1 2.9

Portable Heater.............................................. 16.0 1.1 3.9 4.1 4.4 2.4

Built-in Electric Units...................................... 2.2 0.6 0.6 0.5 0.3 Q

Heat Pump..................................................... 0.6 Q Q 0.3 Q Q

Other Equipment............................................ 1.3 Q 0.2 0.4 Q 0.4

Fuel Oil.............................................................. 0.4 Q Q Q N N

Wood................................................................. 8.9 1.5 1.6 2.0 2.3 1.4

Fireplace........................................................ 6.7 0.9 0.9 1.6 2.0 1.3

Heating Stove................................................. 2.2 0.5 0.8 0.5 0.4 Q

Other Equipment............................................ Q Q Q Q Q N

Propane/LPG..................................................... 2.3 0.3 0.6 0.7 0.5 Q

Kerosene........................................................... 0.9 Q 0.3 0.3 0.2 N

Other Fuel.......................................................... 0.2 Q Q Q N N

 1. One of five climatically distinct areas, determined according to the 30-year average (1971-2000) of the annual heating and cooling 

degree-days. A household is assigned to a climate zone according to the 30-year average annual degree-days for an appropriate nearby 

weather station.

 Q = Data withheld either because the Relative Standard Error (RSE) was greater than 50 percent or fewer than 10 households were 

sampled.

 N = No cases in reporting sample.

 Notes: ● Because of rounding, data may not sum to totals. ● See Glossary for definition of terms used in these tables.

 Source: Energy Information Administration, Office of Energy Markets and End Use, Forms EIA-457 A, B, C of the 2005 

Residential Energy Consumption Survey.

Energy Information Administration

2005 Residential Energy Consumption Survey: Preliminary Housing Characteristics Tables