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Residential Energy Consumption Survey (RECS)

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Table HC10.7 Total square footage of apartment units, 20151

Release date: October 2017
Revised date: May 2018

Number of housing units (million) Total square footage (billion square feet)
  Total
apartment units2
Total3 Heated Cooled
All homes 30.5 28.2 25.6 18.9
Census region and division        
Northeast 7.8 7.4 7.4 3.6
New England 2.0 1.9 1.9 0.8
Middle Atlantic 5.8 5.5 5.5 2.8
Midwest 6.0 5.5 5.5 3.6
East North Central 4.3 4.0 4.0 2.7
West North Central 1.7 1.5 1.5 1.0
South 9.6 9.3 8.1 8.2
South Atlantic 5.4 5.3 4.4 4.7
East South Central 1.2 1.2 1.2 1.0
West South Central 3.0 2.8 2.6 2.5
West 7.2 6.1 4.6 3.5
Mountain 1.8 1.5 1.4 1.2
Mountain North 0.9 0.7 0.7 0.5
Mountain South 0.9 0.8 0.7 0.7
Pacific 5.3 4.6 3.2 2.3
Census urban/rural classification4        
Urban 29.7 27.5 24.9 18.5
Urbanized area 26.2 24.2 21.7 16.4
Urban cluster 3.6 3.3 3.3 2.1
Rural 0.8 0.7 0.7 0.4
Metropolitan or micropolitan statistical area        
In metropolitan statistical area 27.8 25.7 23.1 17.4
In micropolitan statistical area 1.8 1.7 1.7 1.2
Not in metropolitan or micropolitan statistical area 0.9 0.9 0.8 0.3
Climate region5        
Very cold/Cold 10.9 10.2 10.2 5.6
Mixed-humid 8.7 8.2 8.2 6.2
Mixed-dry/Hot-dry 4.4 3.7 2.8 2.5
Hot-humid 5.4 5.1 3.5 4.4
Marine 1.1 1.0 0.9 0.2
Year of construction        
Before 1950 6.0 5.7 5.6 2.7
1950 to 1959 2.1 1.9 1.7 0.9
1960 to 1969 3.6 3.1 2.5 1.6
1970 to 1979 5.4 5.0 4.4 3.5
1980 to 1989 4.9 4.2 3.7 3.2
1990 to 1999 3.6 3.3 3.0 2.6
2000 to 2009 3.8 4.0 3.6 3.5
2010 to 2015 1.1 1.1 1.0 0.9
Fuels used for any use (more than one may apply)        
Electricity 30.5 28.2 25.6 18.9
Natural gas 17.1 15.5 14.3 9.4
Propane6 0.9 0.8 0.7 0.3
Wood 0.6 0.6 0.6 0.4
Fuel oil/kerosene 1.5 1.4 1.4 0.6
Main space heating fuel        
Natural gas 11.9 11.0 11.0 6.9
Electricity 14.1 13.0 13.0 9.6
Fuel oil/kerosene 1.4 1.3 1.3 0.5
Propane Q Q Q Q
Wood Q Q Q Q
Do not use heating equipment 2.8 2.6 0.0 1.7
Type of air-conditioning equipment used (more than one may apply)        
Use central air-conditioning equipment 14.9 14.6 13.1 14.6
Use individual air-conditioning units 11.1 9.9 9.5 4.9
Do not use air-conditioning equipment 5.1 4.3 3.5 0.0
Fuel used by main water heater        
Natural gas 14.0 12.6 11.5 7.5
Electricity 15.1 14.4 12.9 10.9
Propane 0.4 0.4 0.3 0.2
Fuel oil/kerosene 1.0 0.8 0.8 0.3
Some other fuel Q Q Q Q
Indoor light bulbs installed        
Fewer than 20 12.3 10.7 9.6 6.9
20 to 39 9.5 8.8 8.1 5.8
40 to 59 4.4 4.2 3.8 2.7
60 to 79 3.8 4.0 3.6 3.0
80 or more 0.5 0.6 0.5 0.5
Total number of rooms (excluding bathrooms)        
1 or 2 5.1 3.4 2.8 2.4
3 7.2 5.7 5.3 3.7
4 9.9 9.2 8.5 5.9
5 5.5 6.2 5.7 4.4
6 2.2 2.6 2.3 1.8
7 0.5 0.7 0.7 0.5
8 Q Q Q Q
9 or more Q Q Q Q
Number of bedrooms        
0 3.1 2.0 1.7 1.5
1 9.9 8.0 7.4 5.1
2 13.9 13.6 12.4 9.5
3 3.1 3.9 3.4 2.3
4 0.5 0.6 0.6 0.5
5 or more Q Q Q Q
Adequacy of insulation        
Well insulated 8.2 7.8 7.1 5.7
Adequately insulated 14.8 13.8 12.6 9.6
Poorly insulated 6.5 5.8 5.4 3.2
No insulation 1.1 0.9 0.6 0.5
Type of glass in windows        
Single-pane glass 16.7 15.0 13.4 9.9
Double-pane glass 13.6 12.9 12.1 8.8
Triple-pane glass 0.3 0.3 Q 0.2
Number of household members        
1 member 12.4 10.6 9.9 7.2
2 members 9.6 9.0 7.9 6.0
3 members 4.1 3.9 3.5 2.7
4 members 2.7 2.7 2.4 1.8
5 members 1.1 1.3 1.2 0.8
6 or more members 0.6 0.7 0.7 0.4
2015 annual household income        
Less than $20,000 10.6 9.2 8.6 5.6
$20,000 to $39,999 8.1 7.4 6.6 5.0
$40,000 to $59,999 3.9 3.8 3.4 2.5
$60,000 to $79,999 3.4 3.3 3.1 2.3
$80,000 to $99,999 1.5 1.6 1.4 1.2
$100,000 to $119,999 1.1 1.2 1.0 0.9
$120,000 to $139,999 0.6 0.5 0.5 0.4
$140,000 or more 1.3 1.3 1.0 1.0
Ownership of housing unit7        
Owned 3.3 3.8 3.2 2.8
Rented 27.2 24.4 22.5 16.1

1Housing characteristics data were collected between August 2015 and April 2016.
2Total apartment units includes all primary occupied housing units in apartment buildings in the 50 states and the District of Columbia. Vacant housing units, seasonal units, second homes, military houses, and group quarters are excluded.
3Total square footage includes all basements, finished or conditioned (heated or cooled) areas of attics, and conditioned garage space that is attached to the home. Unconditioned and unfinished areas in attics and attached garages are excluded. The square footage for some housing units was calculated based on measurements taken by the interviewer. For households responding without the presence of an interviewer, square footage was imputed based on characteristics of the housing unit. See 2015 RECS Square Footage Methodology for full details about data collection and processing.
4Housing units are classified using criteria created by the U.S. Census Bureau based on 2010 Census data. Urbanized areas are densely settled groupings of blocks or tracts with 50,000 or more people, while urban clusters have at least 2,500 but less than 50,000 people. All other areas are rural.
5These climate regions were created by the Building America program, sponsored by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE).
6Households that use propane only for outdoor grilling are excluded from the RECS estimate of households using propane.         
7Rented includes households that occupy their primary housing units without paying rent.

Q = Data withheld because either the Relative Standard Error (RSE) was greater than 50% or fewer than 10 cases responded.

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

Source: U.S. Energy Information Administration, Office of Energy Consumption and Efficiency Statistics, Forms EIA-457A and EIA-457C of the 2015 Residential Energy Consumption Survey.