Buckle in for a brutal free-fall in home prices and US housing is in a massive bubble, experts say. Here's how bad Jeremy Siegel, Paul Krugman and 5 others think it could get.

The slump in the US housing market is only going to get worse as surging mortgage rates scare away buyers, according to experts.

There are clear signs of stress. In September, existing home sales fell for the eighth month in a row, the longest slide since 2007. There was a decline in the number of new home listings.

The Federal Reserve is raising interest rates to fight inflation, which has been going on for 40 years. Mortgage rates have doubled in the last 20 years.

Mortgage applications are at their lowest since 1997 because of that. Demand has been affected by concerns about an economic downturn.

Here's what 7 top experts are warning about what happens next.

The professor of finance is Jeremy Siegel.

Siegel said in a recent interview that he expects housing prices to fall 10% to 15%.

He said in an interview with CNBC that he thinks we're going to have the second-biggest housing price decline since the end of World War II. It's a very important factor for wealth and equity in the housing market.

Mark Zandi, chief economist at Moody's Analytics 

"Go ahead and do it." "Alright, go ahead and do it." "Alright, go ahead and do it." "Alright, go ahead and do it." "Alright, go ahead and do it." If the economy is not in a recession, then national house prices will fall almost 10% peak to trough. Most of the declines will happen soon. House prices will fall if there is a recession.

He said that the housing market is the most interest-rate sensitive sector of the economy. It's at the forefront of the Fed's efforts to bring down inflation.

The housing market is going to go through a downturn. It will be brutal. There is no part of the market that isn't vulnerable.

A veteran economist and research chief.

Right now, we have a huge housing bubble. Most of the household balance sheet is residential real estate, and most of the time it's in the form of equity, according to an interview released this week.

The Fed is trying to bring inflation down to 2% from its current rate of 8%.

They would like the stock market to fall. Home prices need to go down. What's the reason? There isn't a snowball's chance in hell that they will get to 2% consumer inflation. It is absolutely needed.

Paul Krugman is a winner of the economics prize.

The veteran economist thinks there will be a downturn, but he doesn't think higher rates will hurt home prices.

The Fed's rate hikes have led to a decline in building permit applications. He said in a recent comment piece that construction employment hasn't begun to decline because many workers are still busy finishing houses.

The effects of the housing slump are still months away.

Ian Shepherdson is an economist.

The steep drop in home sales hasn't hit bottom yet, and even buyers who set their sights lower will still face bigger mortgage payments.

The strategist said in a note last week that they expected a drop of 15 to 20% over the next year.

Housing is in free fall. Most of the hit has been in sales volumes, but prices are falling as well.

Don Peebles, real estate developer and Peebles Corp. CEO

The housing market is headed for a recession. Last week, Peebles told Fox News that price declines have already started.

I think we have a freight train that is out of control, speeding up, and no one is looking to slow it down or stop it. He said that it was going to crash into the station.