Wooden Shed Roof Condensation

Entire roof of the shed is damp, particularly around any knots in the wood so am convinced this is dew or condensation and not a leak. is there any sense in putting a simple air vent at the top of the apex of the roof to try and let the warm air out and reduce the temperature difference?. My problem is that the shed suffers from severe condensation that forms on the roof and drips down onto the floor creating puddles. the summerhouse on the other hand never has any indication of damp whatsoever. could the condensation in the shed result from there being no wooden floor.. A wooden shed i have occasionally used in the past does that too. everytime you go there you have to spend time clearing webs from the lights and mains sockets. it was the dryness of that which made me wonder why i put up with the pod's condensation problem..

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