83% of non-homeowners say student loans are the reason they can't afford to buy

Fewer young people are buying houses than their parents and grandparents did at the same age. And for many, student loan debt might be to blame.

In its 2019 Home Affordability Report, home co-investment company Unison found that 83% of non-homeowners said student debt is the reason they can't afford to buy a home right now. Generally, they're delaying buying a house by around seven years because of it, the report found.

That's especially true for millennials: "A recent study by the Federal Reserve found that every $1,000 increase in student loan debt causes a 1 to 2 percentage point drop in the homeownership rate for student loan borrowers during their late twenties and early thirties," Miron Lulic, founder and CEO of financial comparison site SuperMoney, tells CNBC Make It.

It's not surprising, given the rising cost of higher education. "Student loans are the fastest growing source of debt for U.S. households," Lulic says. "Since 2007, student loan debt has grown three times faster than auto loans and 150 times faster than mortgages."

For the 1987-1988 school year, students at public four-year institutions paid an average of $3,190 in tuition, according to College Board's "Trends in College Pricing 2017" report. But for the 2017-2018 school year, that average had risen to $9,970 — a nearly 213% increase.

Private schools are even more expensive. A 1989 graduate of Harvard University, for example, would have spent around $18,000 on tuition during their senior year. For the 2018-2019 school year, tuition costs $67,580. That marks a 275% increase.

However, while student loan debt remains a problem, Lulic points out that it's not the only thing preventing young people from becoming homeowners.

"While increasing levels of student loan debt are a contributing factor, home price inflation (especially for coastal cities) and lifestyle choices are likely bigger factors in the declining home ownership rates among young people," he says.

The combination of stagnant wages and rising costs of owning a home could also make a difference: Between 2017 and 2018, monthly mortgage payments on median-priced homes grew 12%, while median incomes only rose 6%, Unison reports.

As Lulic clarifies, "College price inflation is a problem, but the narrative that student debt is the driving force behind declining homeownership rates among young people is likely an inaccurate conflation."

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