Insulation material for Cali

[drmanhattan]

Over the last winter, when using the Cali heater, I noticed a fair amount of condensation forming inside the kitchen cupboards, where the warm air reacts with the cold metal bodywork. From looking inside other Calis, it seems I'm missing some of the insulating material particularly under the sink and hob, which is probably the root cause. Does anyone know what insulating material I should try to get to prevent this condensation?