KDB was awarded a Design Build Mechanical Contract to design and build the 1.262 million square foot Hotel Convention Center. The Hotel has 16 stories above grade which contain 1,175 guest room suites, three full size luxury restaurants, four bars, a two level spa-fitness center and a grand enclosed glass ceiling atrium. The Hotel has 9 stories below grade which contain two 38,000 square foot ballrooms, 46 meeting rooms, 2 full service kitchens, back of house support services and 2 levels of valet parking. There is also a below grade tunnel located off the grand ballroom for public access into the DC Convention Center across the street.
The facility has over 52 miles of plumbing and HVAC piping systems. Building cooling is provided by four chillers producing 2400 tons of chilled water and building heating hot water is provided by 5 high efficiency gas fired hot water boilers. Ventilation is distributed by 33 central air handlers, 4 heat recovery units, 1424 fan coil units and 112 ventilation fans. The building design includes a fully automated smoke control system for all areas below grade and public areas above grade. The plumbing system serves over 4,500 guestroom and kitchen fixtures. Specialty systems include a fully automated central grease waste removal system for the hotels main kitchens and 40,000 gallons of ozone treated storm water storage which is recycled back into the building cooling towers. The hotels domestic hot water system has over 16,000 gallons of storage produced by 6 high efficiency gas fired boilers.
The Marriott was the 9th project in the world to be built top down — built down 5 floors in the ground before one level could be done above grade.