American homeowners are using less space than ever before

There may not be a lot of homes for sale these days, but there is a lot of housing space sitting empty. In fact, the most in recorded history.

The number of extra bedrooms, which is defined as a bedroom in excess of the number of people in the home, and even including one for an office, has reached the highest level since the U.S. Census began recording this metric in 1970, according to a new report from Realtor.com.

Last year, which is the latest Census data available, the number of extra bedrooms reached 31.9 million, up from 31.3 million in 2022. Back in 1980, there were just 7 million extra bedrooms.

The fourfold jump comes as the number of people in any given household has declined, from a high of 3.1 persons per household in 1970 to a record low 2.5 per household in 2023.

“We are seeing more guest rooms for two main reasons: homes getting bigger and household size getting smaller,” said Ralph McLaughlin, senior economist at Realtor.com. “What’s more, we find that spare rooms are more popular in cheaper areas where it’s more affordable to buy a home with extra bedrooms.”

The average size of a new home grew during the famous “McMansion” era, beginning in the 1980s, when builders went big. But they stopped growing about a decade ago; much of that has to do with rising costs as well as both energy efficiency and environmental demands from consumers.

So the average number of bedrooms per home over the past 50 years has increased, from an average of 2.5 rooms in 1970 to 2.8 rooms in 2023, but there has been no change over the past 10 years.

Looking regionally, since all real estate is local, excess space trends are highest in the Mountain West and in the South. That is simply because there is more land there, and homes are built with larger floor plans, according to the report. Urban homes have just the opposite dynamic.

“If people value having extra space, then we didn’t overbuild during the McMansion era. But if homebuyers are simply tolerating these big homes because they’re what’s available, then perhaps we did overbuild a bit over the past few decades,” McLaughlin added.

The 10 markets with the highest share of total bedrooms that could be considered excess are:

1. Ogden, Utah (12.2%)
2. Colorado Springs, Colo. (12.1%)
3. Salt Lake City, Utah (12%)
4. Memphis, Tenn. (11.8%)
5. Atlanta (11.6%)
6. Cleveland (11.3%)
7. Wichita, Kan. (11.3%)
8. Columbia, S.C. (10.8%)
9. Charleston, S.C. (10.7%)
10. Jackson, Miss. (10.7%)

The 10 markets with the lowest share of total bedrooms that could be considered excess are:

1. Miami (5.9%)
2. Sarasota, Fla. (6.4%)
3. New York (6.5%)
4. Los Angeles (6.6%)
5. New Haven, Conn. (6.7%)
6. Worcester, Mass. (6.9%)
7. Stockton, Calif. (6.9%)
8. Bakersfield, Calif. (7%)
9. Honolulu area (7%)
10. Providence, R.I. (7.1%)