This is a common problem and one that many donâÂÂt consider in the design of a breezeway. Depending on your climate and time of year, the moisture is likely related to the temperature differential from the exterior and interior of the breezeway. In addition no heat (sunshine) to evaporate the moisture.

The sun heats up the breezeway during the day and when it cools down in the evening, moisture builds up on the interior. Making the problem worse is the breezeway doesnâÂÂt likely get full sun exposure to burn off this moisture during the day. The moisture get trapped until the space is properly ventilated or humidity levels outside get low enough to dry the structure. Same thing with condensation in greenhouses.

IMO, most breezeways should either be insulated and conditioned (I know, I know, whatâÂÂs the point). Or left wide open with as much ventilation as possible and no insulation. I would only use building materials that are impervious to moisture inside the breezeway if it's being left wide open. I.e. NO sheetrock, interior grade carpet, interior latex paint, etc. etc. etc.

Without seeing the structure, it's hard to give a solution. The answer will likely be what I stated in the previous paragraph however.

Here in MO sometimes in the spring it can be cold and suddenly very warm and humid (like the next day). My garage floor is still cold so when I open the door, warm humid air comes in and condenses on the floor.

Ventilation is the key. When it gets wet from condensation, open everything up to get it dried out asap. Maybe if it happens during certain seasons, either keep it completely closed up or completely open during those times.