Empty nesters may be able to help ease housing headaches in Sacramento.

Nine out of ten baby boomers and older Americans want to stay in their homes even if costs rise, according to a Trulia report published Wednesday. Meanwhile, millennials are struggling with high housing prices and rent.

The Sacramento area is seeing some of the fastest rising rent in the nation and the prices will likely continue to climb due to a shortage in new apartment units and an influx of people moving in from other metro cities, mostly from the Bay Area.

Stockton is also experiencing rent hikes that have caught the country's attention.

In Sacramento's case, more housing units or rooms would provide a significant amount of relief from the high rent costs. And baby boomers with spare rooms, known as "boom-mates", can play a role in adding more open units to the market.

According to the Trulia report, tens of thousands of homes in the U.S. have nearly 3.6 million unoccupied rooms that could be rented out. Retired baby boomers and soon-to-be-retired baby boomers can make as much as an additional $14,000 a year simply by renting out a spare room in their home.

For younger adults, the option of living with a "boom-mate" as opposed to a one-bedroom apartment could save them $24,000 annually, the report states.

In the Sacramento area, there are 41,336 spare rooms, according to Trulia data. The Stockton-Lodi market has 8,451 unoccupied rooms.

A recent RentCafe study found the Sacramento region has gained nearly 29,000 new residents so far this year. However, only 738 new apartment units are slated for completion by the end of the year. Sacramento is also seeing a high occupancy rate at 96.7 percent.

The more than 41,000 spare rooms available in the region could provide a sigh of relief for those struggling to find rentals in the now-competitive area, especially millennials in need of affordable housing.

The Sacramento area is home to a number colleges and universities, such as UC Davis and Sacramento State. Many universities now offer exchanges where older Americans and families host a students on a budget.

Sacramento has more spare bedrooms than San Francisco, which has about 22,000 spare rooms. However, San Francisco has the most profitable market for room rentals, earning the room's landlord nearly $22,000 a year and saving a renter more than $14,000 annually.

In addition to financial gains, the study also found other benefits to multi-generational households.

While the boom-mate trend hasn't quite hit the U.S., it's a popular option in Europe, according to the report. Increased social interaction between the young and older can help fight dementia and regulate blood pressure. It can also eliminate feelings of loneliness, which has been linked to increased mortality rate.

Older generations can provide guidance and wisdom to their younger roommate while in exchange, baby boomers can learn new technologies, ideas and perspectives.