Falling stocks mean cheaper mortgages. But what’s the big picture for housing?

The big sell-off in stocks that began last week has already sent mortgage rates plummeting, but so far that’s only translated into more demand for refinancings.

The bigger questions for housing markets are whether stock market volatility will undermine homebuyer confidence, and whether declines in equity prices will mean buyers will have a harder time scraping together down payments.

Jan. 1 reductions in FHA loan limits already have builders offering discounts.