Steel Roof Sweating

Metal gets cold faster than other items so condensation begins on metal first.

Steel roof sweating.

Picture a cloud of moisture floating overhead between the rafters. The condensation occurs most commonly on the roof as the warmest most moisture laden air rises to roof level. Condensation on metal roofs can be a problem once the weather starts to get cold. When the temperature of the roof is lower than the air inside the extra moisture in the air condenses on the underneath of the roof.

At night the thin metal in the roof quickly cools down. Warm wet air rises and meets the cold roof and cools. Metal roofs are known for this with condensation forming particularly at the beginning and end of a day. If the tin roof sits on top of another material such as wood then you can get a case of wood rot.

Traditionally condensation is managed by insulating the metal roof so that the panel temperature never reaches the dew point. Metal roofs must be laid flat on a vapor barrier because steel will condensate if there s any air space underneath it. It can lead to roof leaks even if rain has not occurred for several days. Ok now we understand a bit how the condensation in metal sheds happens.

Metal roof over shingles condensation. Essentially condensation occurs at night when the temperature inside a building is warmer than outside. Put the steel down directly on a vapor barrier. Condensation happens when moisture filled air contacts anything that is below the dew point temperature.

When then environment outside becomes cooler i e. The result is the roof sweating and dripping water all over your precious stuff. It doesn t matter if the air space is a half inch or six inches because the condensation factor will remain the same. As it cools it can t hold as much moisture.

The prime reason for this is due to the temperature differential between the inside and the outside of the shed. That excess moisture ends up as drops of condensation on the roof. Metal roof sweating is a result of excess humidity condensing on the underside of your roof.