The gains were a continuation of the US market's positive bent Tuesday, when the S&P 500 and Nasdaq finished at records following strong earnings from Netflix.

US housing starts and building permits both notched strong gains in June, a sign homebuilders may finally be responding to soaring demand, according to government data. Home construction started last month jumped 8.3 percent, well above analyst expectations for a 3.3 percent increase.

Meanwhile, Morgan Stanley reported especially strong earnings, which rose 2.6 percent after reporting an 11.4 percent rise in second-quarter profits to $1.6 billion.

About 35 minutes into trading, the Dow Jones Industrial Average was at 21,600.33, up 0.1 percent.

The broad-based S&P 500 added 0.3 percent to 2,468.26, while the tech-rich Nasdaq Composite Index jumped 0.5 percent to 6,373.60.

Dow member IBM sank 4.1 percent after suffering its 21st straight quarter of declining revenue as second-quarter net income dipped seven percent to $2.3 billion.

United Continental dropped 3.9 percent despite scoring a 39 percent rise in second-quarter profit to $818 million. Analysts cited disappointment with aspects of its third-quarter forecast.

Spice company McCormick dropped 5.2 percent after sealing a deal to buy British consumer health giant Reckitt Benckiser for $4.2 billion. The acquisition covers Reckitt's food brands such as French's mustard.

Scripps Networks Interactive, owner of the Food Network, surged 16.6 percent on reports it held separate talks with Discovery Communications and Viacom on a potential takeover. Discovery gained 5.6 percent and Viacom won 1.6 percent.