Driving through the sprawling Craig Ranch community, you’d never know that North Texas housing construction is at the lowest point in two decades.

Builders are pouring foundations and putting up framing for homes in the McKinney project — thanks in part to the efforts of startup firms that are taking advantage of the down market.

One of the busiest is Dunhill Homes, a company that just began building in the Dallas area this year.

“We are probably going to have 60 to 70 starts this year, and our first community didn’t open until May,” said Dunhill’s John Mann. “We already have five communities going in Dallas-Fort Worth.”

Dunhill last year built houses in the Las Vegas area, then leapfrogged to North Texas with locations in McKinney and North Fort Worth.

“We were able to get into a bunch of good communities before the lot prices started going crazy,” said Mann, who was previously a top officer with Meritage Homes. “For a ‘no name’ builder, we are selling pretty well — 12 homes just last month.”

Dunhill is part of the small cadre of residential companies to get under way since the housing crash began five years ago.

Single-family home construction in the Dallas-Fort Worth area has plunged almost 75 percent since 2006. And almost half of the homebuilding firms that were active in North Texas have shut down or pulled out of the market.

“We are today at about 43 builders, down from 80 at the peak of the market,” said Ted Wilson, principal with Dallas housing analyst Residential Strategies.

One of the country’s biggest homebuilders — Ryland Homes — announced plans last week to sell off more than 1,000 lots in North Texas and withdraw from the market.

“It’s very competitive here, and that — as much as anything — had to be weighing on the folks at Ryland’s minds,” Wilson said. “At one time they were building over 1,000 units here and had dropped to 120” in the last year.