The Automist pump is not much bigger than a kitchen kettle and will fit in a cupboard or under the sink. It is only 385 mm (height) by 216 mm (length) by 181 mm (width) and weighs 6.0 kg, and doesn't require a tank. A sprinkler (category 1) is usually supplied by a stored water tank (1200L) that weighs approx. 1.2 Tonne. It is generally located in the attic, sometimes needing to be reinforced to take this load. If your sprinkler is category 2, 3000-4500 litres is required, weighing 3 to 4.5 tonnes, and if it is category 3, 6000-9000 litres at 6 to 9 tonnes.