How to Prevent Rusting on Metal Roofs by Solving Condensation Problems

Installing Roof Repairs Sydney Wide Specialists over commercial and residential buildings, including sheds, garages, and barns is simple and cost-effective. If properly maintained, powder-coated or galvanized metal roofs can last for a lifetime. Iron is harmed by moisture and oxygen, which are combined.


In winter and when it rains, the temperature outside is usually lower than inside. The combination of lower temperatures outside and higher levels of humidity inside leads to the formation condensation on metal roofs. Metal Roof Condensation can cause drips, but the long-term impact of this is metal corrosion. The roof will need to be completely replaced if the part is neglected. No amount of patching can prevent future leaks. The condensed moisture can be damaging if metal is placed over felt, glass wool or plywood.

To prevent such problems, you can replace your entire roof with fiberglass or plywood sheets. Some have tried to attach plastic sheets as vapour barriers on the roof, but this is an ineffective and cumbersome process. Glass wool is often used in bags attached under the roof to provide insulation. The condensation of humid air that penetrates through cracks and gaps can cause water to accumulate and wet insulation. The water doesn’t dry quickly, and when combined with the oxygen in air it corrodes the iron sheets. When roofs are equipped with under-decks the issue isn’t apparent until there has been a lot of corrosion and rainwater starts to leak in.

The undersides of roofs made from metal tin can be coated to prevent condensation. It is possible to prevent corrosion by painting, but this will not prevent condensation. Water will still drip. Covering the underside with foam is a better solution to both protect the tin sheet and prevent condensation. It acts both as a vapour-barrier and as insulation, keeping warm air from the inside of your home away from cold surfaces and preventing condensation.