FHA insured mortgage defaults to unlock home lending

Depression-era mortgages typically required 50 percent down and full repayment within three to five years, ending in a large balloon payment few borrowers could actually make — terms that reflected how completely lenders bore the risk of default themselves. By 1933 up to half the country's home mortgages were in default, and with housing finance near total collapse, banks had every rational reason to keep tightening terms rather than loosen them, shrinking the pool of eligible buyers further.

Every buyer without significant savings was locked out regardless of their actual ability to make monthly payments over time, because the product that would have suited them — a long-term, low-down-payment, fully amortizing loan — was exactly the structure lenders now considered too risky to offer after watching half the market default.

The National Housing Act of 1934 created the Federal Housing Administration, which insured private lenders against borrower default on qualifying mortgages: if a borrower stopped paying, the FHA, not the bank, covered the lender's remaining loss, funded by insurance premiums paid into the program by the borrowers themselves.

The FHA insured lenders against borrower default, funded by borrower-paid premiums, so banks could lend generously without bearing the loss that stopped them.

Banks bore all default risk, so they demanded high down payments and short terms.

FHA insurance shifted default losses from banks to the government, funded by premiums.

With risk off their books, banks could offer long-term, low-down-payment loans.

Premium funding kept underwriting disciplined, so the program stayed solvent.

When a counterparty won't offer better terms, check if it's about risk allocation; insure the specific risk instead of changing their judgment.

With default risk moved to government, lenders offered 20-to-30-year amortizing mortgages with down payments as low as 10 percent. The FHA-insured mortgage became the template for the modern long-term, low-down-payment American home loan, and its insurance model later extended into VA loans, Fannie Mae, and the broader system of government-backed mortgage finance still in place today.