This 500 litre rectangular loft tank is built to fit into a roof void or ceiling space, giving gravity-fed backup water storage without taking up ground space. Buy from REXE Roofing Products. Compact rectangular shape fits between roof trusses and rafters UV-stabilised, food-grade polyethylene, safe for drinking water Gravity feed boosts pressure to taps and showers below Top filling lid and bottom outlet, ready for standard fittings