Huttig Building Products, St. Louis, MO, distributor of millwork, building materials and wood products, has closed its distribution facility in Hauppauge, NY, as part of the company's effort to downsize in response to the recent downturn in the housing market.   ; About 30 jobs will be eliminated.   ; While we continue to believe the Long Island, NY, market has long-term potential for more localized distribution of millwork and specialty building products, unfortunately now is not the time for making the additional investments that would be required in today's market environment, said President and CEO Jon Vrabely.   ; Huttig has 41 distribution centers serving 46 states. It serves mostly building materials dealers, national buying groups, home centers and industrial users, including makers of manufactured homes.