[sheeny (Al)]

G'Day Terry.

Condensation is caused by the surface of your dome being cooled below the dew point of the air. Heating would solve it, but it's not a very good solution.

In normal buildings, this is why a vapour barrier is used (the shiny aluminium foil - sisalation). The sisalation keeps a sealed quantity of air between it and the roof so any condensation is minimised (no air movement to bring more moisture in), and condensation hopefully doesn't occur on the sisalation due the air gap insulating it from the cold roof.

If you have a slot type dome, you might be able to insulate the dome with foil backed insulation, but remember to seal the foil all around to make an effective vapour barrier, otherwise it could all end up a sodden mess.

I'm getting a little bit on condensation inside my POD this winter but I can't insulate inside as half the dome slides inside the other half, but at least the POD has a double skin, so the problem isn't bad.

Al.