By Prerana Bhat and Indradip Ghosh

BENGALURU (Reuters) - U.S. home prices will rise steadily over the next few years amid prospects for modest interest rate cuts by the Federal Reserve and as many existing homeowners keep their doors closed to selling, according to property experts polled by Reuters.

As aggressive Fed rate hikes have sharply pushed up the cost of standard 30-year mortgages to more than 7%, existing homeowners have held on to rock-bottom rates from the pandemic, some below 3%, limiting the supply of homes for sale.

That, combined with relentless demand for a place to live and a strong economy, cushioned a brief correction in the market. Average house prices soared around 50% during the pandemic and again hit a new record last year.

After rising about 6% last year, defying previous expectations of declines, average home prices are forecast to grow 3.3% this year and around 3.0% in 2025 and 2026, according to the median of 28 analysts in a Feb. 15-March 1 Reuters poll.

Forecasts were based on the S&P CoreLogic Case-Shiller composite index of 20 metropolitan areas.

That outlook was upgraded very slightly from three months ago, modestly outpacing expectations of headline inflation, seen averaging 2.7% and 2.3% this year and next, respectively, according to a separate Reuters survey.

"Despite rapidly climbing mortgage rates in 2023, record low levels of resale inventory have contributed to home prices' resiliency... We expect to see some small gains in home prices as mortgage rates stabilize and reach a more terminal rate over the next year," said Crystal Sunbury, senior real estate analyst at RSM, a U.S.-based consulting firm.

The 30-year fixed mortgage rate, which broke above 7.0% recently for the first time since December, was expected to average 6.50% this year and decline only modestly to 5.98% in 2025 and 5.75% in 2026, according to median forecasts in the poll.

"We may see more resale units come into the market, as mortgage rates ease, but resale inventory is not expected to climb substantially, as over 80% of current homeowners are estimated to have mortgages under 5% and the vast majority will not be willing to trade up their mortgage for a higher rate," Sunbury added.

Average mortgage rate forecasts were broadly upgraded from a November poll and reflect retreating expectations for the number of Fed rate cuts expected later this year, currently due to start in June.

Shelter costs as a category, which is dominated by rental costs rather than home prices, comprise around one-third of the consumer price index. Although the Fed targets the personal consumption expenditure index - which is less driven by housing - higher house prices could delay Fed rate cuts.

On the prediction mortgage rates would decline only slightly, existing home sales, which comprise about 90% of total sales, were seen around current levels of 4 million units this year, much less than over 6 million during the pandemic.

A persistent shortage of previously owned homes pushes buyers into the new home and rental market, adding pressure on already lagging constructions and sales.

Responding to a separate question, 22 strategists were evenly split on whether the ratio of homeowners to renters would increase or decrease.

A further 15 of 23 said the gap between demand for affordable homes and supply of them would stay around the same or widen over the next 2-3 years.

"Overall, the main issue in the housing market is affordability, and mortgage rates are not going to fall enough to make a dent," said Brad Hunter of consultancy Hunter Housing Economics.

"Newly-formed families used to be 'entry level' for the builders. Not anymore. Young families have essentially no hope of buying a new home for their first home. Even on the resale market, they will continue to struggle just to become homeowners at all."

(For other stories from the Reuters quarterly housing market polls:)

US home prices to grind higher as cheap mortgage holders stay put: Reuters poll