The house prices peaked in 2006, and then it fell about 30 percent until it hit bottom in 2011. After that house prices have been increasing steadily and it is almost close to its pre-recession peak levels. However, the San Francisco Federal Reserve claims this is not another bubble.

According to a post by researchers in the official website of the Federal Reserve Bank of San Francisco, the increase in the house prices since 2011 has a staggering difference from the housing boom in the mid-2000s. The housing boom since 2011 is a credit-fueled bubble where housing valuation increased with a self-reinforcing loop. That valuation is measured by house price-to-rent ratio, as well as household leverage, which is measured by the mortgage debt-to-income ratio. Meanwhile, the more recent house price growth has a valuation increase that is less-pronounced and it has an outright drop in housing leverage. That pattern doesn't point to a credit-fueled bubble.

Bloomberg writes that San Francisco Fed President John Williams warned that monitoring asset price bubbles is vital. Preventing imbalances from accumulating can lead to interest rate hikes. In October he said he was seeing signs of imbalances in real estate and other high asset prices. He said once these issues become too big, it will be difficult to address them. However, he said the market hasn't reached its tipping point yet, and the recent report from the San Francisco Federal Reserve confirms that claim.

The Business Insider reported that the constant downward curve of the household leverage reflects a healthy appreciation of the present home prices, according to the Fed. It also means that there is a steady removal of factors that inflated the pre-crisis bubble. These factors help ensure that there won't be another credit-fueled housing bubble. 

The researchers from the Federal Reserve Bank of San Francisco wrote that there are no red flags from the current housing rebound, but still advised policy makers and regulators to be vigilant to make sure the housing bubble of the mid-2000s can be prevented.