The number of homes under construction in Tomball, Magnolia and Pinehurst ZIP codes increased in 2017 and the first quarter of 2018 after a decline, which began in late 2014, according to quarterly data from Metrostudy. Throughout the Greater Houston area, new home construction is also up in the first three months of 2018. Houston added 6,693 new homes under construction—the second-highest first-quarter starts in a decade, according to a report from Metrostudy.