Drying a Store Room Below the Silverfish Threshold: Dehumidifier Capacity From a Moisture Balance

Silverfish breed freely in humid rooms and largely stop below about 60 percent relative humidity, so drying a room is a control measure in itself. This study sizes the dehumidifier for a 48 m3 basement store room at 20 C by moisture balance: infiltration of 0.7 air changes per hour of air at 26 C and 80 percent relative humidity, plus 180 g per day of wall and ground ingress. Holding 75 percent relative humidity requires removing 3.99 L per day; holding 60 percent requires 6.08 L per day, which at a stated derating factor of 0.55 for cool-room duty means buying a machine rated at 11.06 L per day. Holding 55 percent needs a 12.33 L per day rating. The originated rule is therefore to select a dehumidifier with a nameplate rating of at least 12 L per day for a room of this size and climate load, and to expect a smaller 'bedroom' unit rated near 7 L per day to stall around the 75 percent level where silverfish continue to breed. This study is simulated, not measured. SIMULATED, NOT MEASURED.