Multigenerational living is becoming more popular and widespread. The trend is likely to boost demand for house plans designed for several generations living under one roof. According to the American Community Survey data, in 2012 there were 4.4 million multigenerational households residing in the United States, accounting for more than 5.7 percent of all family households. This represents a noticeable increase since 1990, when there were 2.9 million multigenerational households accounting for only 4.5 percent of family households. That equates to a 26.7 percent rise in share.
The most common type of multigenerational household is one in which a householder lives with a child and a grandchild. These accounted for close to two thirds of all multigenerational households in 2012. Even though the number of these families has been increasing, the share of multigenerational households with a child and a grandchild declined from more than 68 percent in 1990 to less than 65 percent in 2012.
The second most common and fastest rising type of multigenerational households is one where a householder lives with a child and a parent. In 2012, these accounted for one third of all multigenerational households, up from 30 percent in 1990. The four-generation households remain quite rare in the United States (less than 75,000 in 2012), consistently accounting for less than 2 percent of all multigenerational households.
Figure 1. Multigenerational Households by Type
Multigenerational households are larger and more likely to live in single-family homes and own their property. On average, these households have 5.1 people compared to only 2.4 persons in other households. In 2012, 79 percent of multigenerational households lived in single-family homes and more than 69 percent owned their homes. In comparison, less than 69 percent of households with two or less generations occupied single-family homes, and the share of homeowners in this group was less than 64 percent in 2012.
Multigenerational households are twice as likely to include foreign-born persons as other households. In 2012, one in three multigenerational households had immigrants, while that share was less than 17 percent among other households with two or less generations.
Multigenerational households are also more racially and ethnically diverse. Close to 63 percent of multigenerational households included either Hispanic or people of races other than White. The racial and ethnical composition of other households, with less than three generations, is almost the exact opposite. Only a third of these traditional households contained Hispanic or racial minorities.
Figure 2. Characteristics of Multigenerational and Traditional Households
Looking at all US households, including one-person-living-alone households, the share of multigenerational households increased from 3.2 percent in 1990 to 3.8 percent in 2012. Their prevalence among family households rose even more, from 4.5 percent in 1990 to 5.75 percent in 2010. The fact that multigenerational households are becoming more common stands in sharp contrast with other well-known demographic trends that have been shrinking household size in the United States, such as the rising share of those living alone and the falling share of families.
At the same time, the increase in multigenerational living coincided with the rising number of young adults choosing to live with their parents–a trend that has become particularly noticeable since 2005. While only one in four young adults ages 18 to 34 lived with their parents or parents-in-law in 1990 and 2000, that share increased to one in three by 2012. This was particularly true for older young adults, ages 25 to 34, whose share living with parents was fluctuating around 12 percent from 1990 through 2005 and then rose quickly to exceed 19 percent in 2012.
The closer examination of the ACS data shows, however, that the rising share of young adults choosing to stay in parental homes contributed little to the growing popularity of multigenerational households with three or more generations. While the number of these households increased from 1.8 million in 1990 to 2.4 million in 2012, the share of multigenerational households with young adults living with their parents or parents-in-law actually declined. In 1990, 62 percent of all multigenerational households included young adults living with parents. By 2000 this share declined to less than 54 percent and has been fluctuating around this level ever since. This trend is even more pronounced for younger, college-age adults. The share of multigenerational households with young adults ages 18-24 living with parents has been steadily declining from 28 percent in 1990 to 26 percent in 2000 and further to 23 percent in 2012.
Figure 3. Share of Multigenerational Households with Young Adults Living with Parents, Minority and Foreign Born Persons
A much stronger force behind the growing popularity of multigenerational living is the country’s growing ethnic and racial diversity. While 1.53 million multigenerational households included Hispanic or racial minorities in 1990, that number grew to 2.76 million in 2012. At the same time, the share of ethnically or racially diverse multigenerational households increased from 53 to 63 percent. Similarly, immigration provided a strong boost to multigenerational living. The number of multigenerational households with foreign born people increased from 577 thousand in 1990 to 1.5 million in 2012, and their share rose from 20 to 34 percent.
There are various reasons and demographic trends that help explain the rising popularity of multigenerational living. Builders and their architects should be prepared to provide a variety of house plans that reflect the needs of families with several generations choosing to live under one roof.