The U.S. housing market is expected to cross the $50 trillion threshold during the next 12 months, according to a new report from Redfin.

The total value of U.S. homes gained $3.1 trillion over the past 12 months, an increase of 6.6%, to reach a record $49.6 trillion. That more than doubles the total U.S. housing value of $22.5 trillion 10 years ago. A lack of inventory is preventing downward pressure on prices, while at the same time, new construction is driving increases in market valuation, the firm said.

"Mortgage rates have started falling, but many potential sellers and buyers are waiting to make a move, meaning we are likely to continue seeing a pattern where prices slowly tick up," said Redfin economics research lead Chen Zhao. "That's great news for the millions of American homeowners who see their equity rising, but first-time buyers are going to keep finding it tough to find an affordable home."