The Norwesco 400 Gallon Doorway Tank (SKU 43856) is a 400-gallon vertical polyethylene tank built narrow enough to pass through a standard doorway and down a hallway, then stand upright wherever you need bulk water storage. Its narrowest dimension is 29 inches - that is the number your tightest pinch point has to clear - with a 66-inch length and a 70-inch height. That footprint lets it reach basements, utility rooms, garages, and equipment sheds that a full-diameter vertical tank simply cannot. It is molded in natural white polyethylene and carries a 1.5 specific gravity rating.
Will it work for your site?
Plan the install around the footprint and the loaded weight before the tank arrives. The footprint is 29.0 x 66.0 inches and the height is 70 inches. The 29-inch width is the access dimension - your tightest pinch point must clear it - while the 66-inch length governs floor footprint and how the tank negotiates turns, so do not assume you need a 66-inch-wide door. Filled with water this tank holds about 3,336 pounds, and the structure is rated to a maximum contents weight of 5,004 pounds at its 1.5 specific gravity rating. That load has to land on a flat, fully supported, level base - a concrete pad or a continuous floor that can carry it, never blocking or a partial frame. For pad design on an above-ground install, see our concrete pad sizing guide, and to confirm 400 gallons fits your demand, run the Tank Sizing Calculator or read the Tank Sizing Guide. If you are weighing the doorway line across the range, the Norwesco doorway tank sizing guide walks through 100 to 1000 gallon picks by application.
Applications and compatibility
This is a workhorse for indoor and tight-access water storage: bulk water holding, well and hauled-water buffering, rainwater and grey-water collection where access is the constraint, and emergency or fire reserve in buildings where a wider tank will not fit. For reuse and reservoir planning, our guides on industrial water reuse tank topology and fire-water reservoir design for rural and remote sites cover sizing discipline and freeze protection in detail. Rated to 1.5 specific gravity, the tank structure handles water and water-like fluids up to 1.5 SG; for heavier or chemical service, or contents above 1.5 SG, call 866-418-1777 and we will confirm a higher-rated tank and the correct fittings and gaskets for your fluid. Refer to the technical drawing on this page for dimensional confirmation, and contact us at 866-418-1777 to confirm fitting sizes and locations before you plumb it.
The mistake to avoid
The number-one error on a doorway tank is measuring the tank but not the path. The 29-inch width is the whole point of this design - verify every pinch point on the route in, including the door jamb, the swing of the door, stair landings, and railings, before delivery day. The second is the base: a 5,004-pound rated load needs continuous, level support, never blocking or a partial frame. The third is fittings - match every fitting and gasket to your fluid and its specific gravity, because a gasket rated for water is not automatically rated for heavier or chemical service. And note the 1.5 specific gravity rating describes the structural limit; this tank is sold for water service, so keep it to water and water-like contents unless you have confirmed compatibility for anything heavier.
This tank ships LTL freight, quoted live to your ZIP. It is stocked at Norwesco plants nationwide - Griffin, GA; Hanford, CA; Lancaster, OH; Owego, NY; Shawnee, OK; St. Bonifacius, MN; and Washougal, WA - and we ship from the location nearest you to cut transit time and keep freight reasonable. Get a real number with the Freight Cost Estimator, or call us at 866-418-1777 and we will quote it for you and help confirm the 400 gallon doorway tank is the right fit for your space.
