Baby boomers make up more than a third of all homeowners, and more than half don’t even have a mortgage, Eric Finnigan, vice president of demographics for John Burns Research and Consulting, previously told Fortune. So in our current environment, where mortgage rates skyrocketed from historic lows throughout the pandemic to a more than two-decade high in October 2023, being mortgage-free is like hitting the mother lode. It’s partly why boomers aren’t moving—because why give up no mortgage rate, or a substantially lower one, for one that’s in the 6% to 7% range, plus a higher monthly payment? 

On the other hand, some millennials, who haven’t even bought their first home, are looking at a much different housing market than before the start of the pandemic—one where the salary needed to buy a starter home has almost doubled, the cost of owning a home is the highest on record, and low inventory levels are much more dire. 

And baby boomers are sitting on particularly large homes that millennials who are starting families need. A 2024 Redfin analysis from found empty-nest boomers own 28% of the country’s largest homes, those with three bedrooms or more; and millennials with kids own only 14%. As mentioned earlier, there’s simply no financial incentive for the former group to let go of their homes. But it wasn’t always this way. “The landscape has transformed over the last decade: 10 years ago, young families were just as likely as empty nesters to own large homes,” the analysis read. 

Baby boomers are aging in place and have no reason to sell their homes

Last year, existing home sales fell to their lowest level in almost three decades; nobody was selling their home or buying. And apart from there being no financial incentive to sell, boomers are aging in place because they can. In doing so, they’re remodeling and improving their current homes—not only for safety but to live comfortably and luxuriously, Finnigan previously explained. 

For some baby boomers, the idea of renovating their family home—albeit likely too big for their empty nesting—is much more appealing than moving. Plus, there’s a housing crisis for baby boomers who try to move with a shortage of retirement homes. More than half of them have no plans to move, although the majority of them have lived in their current homes for more than a decade, according to a 2024 report by home improvement company Leaf Home and Morning Consult. 

And some baby boomers have spent tens of thousands of dollars—and in some cases hundreds of thousands of dollars—on home renovations to make their homes feel more updated, comfortable, and safe for aging. A Californian couple in their seventies, Brenda Edwards and her husband, spent more than $100,000 on home renovations to accommodate a wheelchair in case they ever need one. 

“We felt comfortable,” Edwards told the Associated Press about why they wanted to stay instead of move. “We have a pool. We have a spa. We just put a lot of love and effort into this yard. We want to stay.” Plus, “it would be too hard to purchase anything else” since their house was nearly completely paid off, she said. 

Many baby boomer homeowners are “opting to upgrade their current homes for the long haul,” Marine Sargsyan, chief economist at home renovation and design site Houzz, told Fortune, rather than deal with higher mortgage rates. So much so that baby boomers lead renovation activity across all generations, according to the site’s 2024 Houzz & Home Study released in March. 

“We’re seeing a growing trend toward universal design elements in kitchens and bathrooms specifically as homeowners ready their homes to age in place,” Sargsyan said. “Changes include wheelchair-accessible pathways, additional lighting, pull-out cabinets, rounded countertops, non-slip flooring, and grab bars.” 

Leaf Home also reports seeing an uptick in demand for walk-in showers and tubs as well as stairlifts, making homes more accessible for aging generations. “We expect to see an increase in boomers’ desire to make improvements for their homes to remain comfortable and safe,” Nina George, chief growth officer at Leaf Home, told Fortune. 

But some baby boomers are selling and some millennials are buying homes. Millennials surpassed baby boomers as the largest generation of homebuyers, according to the National Association of Realtors. 

“The generational tug-of-war between millennials and baby boomers continued this year, with millennials rebounding to capture the largest share of homebuyers,” NAR’s deputy chief economist and vice president of research, Jessica Lautz, said alongside a recent generational trends report. 

A version of this story was published on Fortune.com on June 6, 2024.