Steel Roof Sweating

At night the thin metal in the roof quickly cools down.

Steel roof sweating.

That excess moisture ends up as drops of condensation on the roof. Traditionally condensation is managed by insulating the metal roof so that the panel temperature never reaches the dew point. Essentially condensation occurs at night when the temperature inside a building is warmer than outside. 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.

Metal gets cold faster than other items so condensation begins on metal first. The prime reason for this is due to the temperature differential between the inside and the outside of the shed. The result is the roof sweating and dripping water all over your precious stuff. Warm wet air rises and meets the cold roof and cools.

Picture a cloud of moisture floating overhead between the rafters. Metal roofs are known for this with condensation forming particularly at the beginning and end of a day. The condensation occurs most commonly on the roof as the warmest most moisture laden air rises to roof level. It can lead to roof leaks even if rain has not occurred for several days.

Condensation on metal roofs can be a problem once the weather starts to get cold. Metal roofs must be laid flat on a vapor barrier because steel will condensate if there s any air space underneath it. Metal roof over shingles condensation. Metal roof condensation especially with a tin roof can cause serious problems when the metal sweats or rainwater collects under the tin panels when this happens the tin roof can rust and even warp.

As it cools it can t hold as much moisture. This is often accomplished using vinyl backed fiberglass insulation to prevent humid air from coming into contact with the cooler metal roof which may be at or below the dew point. Put the steel down directly on a vapor barrier. Condensation happens when moisture filled air contacts anything that is below the dew point temperature.

The cold metal in contact with the warm air means that water droplets condensation forms on the inside surface of the shed roof. If the tin roof sits on top of another material such as wood then you can get a case of wood rot. When then environment outside becomes cooler i e.