The rental market in Manhattan south of 96th Street is projected to expand in the next 20-24 months as the pipeline of projects developed over the past several years comes to market. In this area, there will be 4,152 new rental apartments this year (compared to last year’s 3,313); in 2016 the new rental units coming to market should be roughly 8,800 (forecast by Citi Habitats).

The near-term onrush could give way to concerns of a glut, but most experts believe that demand is strong enough to offset the additions on the supply side.

In fact, new inventory is expected to reverse course in 2017 and decline 14 percent to 7,540 apartments, according to the brokerage’s projections. And the culprit is the sky-high prices development sites that are making condos more feasible as opposed to rentals.

By last fall, the average price for a buildable square foot in Manhattan had climbed to $548, up 23 percent from the year before, according to commercial brokerage Massey Knakal Realty Services.

In the short term, the increase this year is largely the result of a couple of mega-projects, most notably the Moinian Group’s 1,174-unit 605 West 42nd Street, the Durst Organization’s 709-unit “pyramid” on West 57th Street and Rose Associates’ 70 Pine Street, which will deliver 644 units.

One result of the higher prices developers are paying for property these days is that it pushes minimum rents up to the areas of $75 and $80 per square foot. People who pay those types of prices expect certain finishes and a certain lifestyle. It’s driving the product quality to a higher level of finish than what was put out five or six years ago.

Nowadays apartments are updated a lot quicker (maybe even every 5 years) and that adds to the acceleration of the rent. The demand for the latest finishes and amenities creates room for growth in those rents. Most experts predict a 5% to 10% rents increase in 2015.

Manhattan is not the only borough in New York City that will see more rental units coming online this year. In fact, the number of rental units coming to market in Brooklyn is expected to jump to 6,527 units from just shy of 3,000 in 2014, according to Citi Habitats.

In Queens, Long Island City alone is forecast to add 1,800 new rentals this year, a bump of 87 percent over last year.

Rents in Queens were up 5.9 percent on the year in December, with a median price of $2,839, according to Miller Samuel. In Brooklyn, the median price of $2,900 was up 9 percent on the year.

Condos grow at faster clip.

While developers are building more rental units in Manhattan this year, rentals in the borough are a decreasing percent of the new residential total.

Last year, rental units in Manhattan accounted for 58 percent of the new residential product, according to Citi Habitats. This year, they will make up only 41 percent. That is because condo production is projected to outpace growth on the rental side this year, expanding roughly 150 percent to 6,097 units.

The opposite is true in Brooklyn, where rental growth outpaces condos. New rentals are expected to make up more than 80 percent of the market in Brooklyn, as well as in Long Island City.