April 1 (Reuters) - U.S. apartment vacancy rate fell to 4.1 percent in the first quarter, from 4.2 percent in the fourth, while new construction declined to its lowest level since the first quarter of 2013, real estate research firm Reis Inc said on Wednesday.
New construction fell to 28,812 units delivered in the first quarter, from 39,436 units in the fourth, as a number of projects were pushed until 2015.
"Although it was a bit surprising that new supply continued to decline during the quarter, this decline likely means that quarters with historically high levels of completions could be on the horizon in the near future," Reis Senior Economist Ryan Severino said.
Rents reached record-high nominal levels during the first quarter. Asking and effective rents rose 0.6 percent during the first quarter, Reis said.
New York remained the most expensive market in the country with effective rents registering $3,200 per month, a 45 percent premium to San Francisco, which remained the second-most expensive market, the report said.
Sacramento, California remained the tightest market in the United States, having the lowest vacancy rate of 2.3 percent.
Reis said it expects the national vacancy rate to rise by 0.7-0.8 percent in 2015 as massive amounts of new supply comes online. It expects rent to rise about 3.5 percent this year.
(Reporting by Ankit Ajmera in Bengaluru)