Living in Coastal areas such as the Gold Coast or Sunshine Coast there is fair chance your roof will be affected by rust or corrosion caused by fine particles of sea salt, usually formed by the evaporation of sea spray. This creates a salt haze that drifts inland on the winds and settles on roofing structures. The salt haze over time corrodes your roofing screws, causing them to rust and weaken. Once corrosion starts the screws will need to be monitored closely or replaced.
Corrosion of roofing screws can also result from acids carried through the air from industry and chemical spraying, U.V. from the sun, or humidity in tropical or moist areas.
Roofing screws are often overlooked as a minor and some building inspection companies fail to report on these all together until it is too late, and the rust has progressed, and the roofing iron must be replaced! Corrosion progresses on the head of the screw and the rubber washers perish overtime. Rust and corrosion run down off the head of the rusty screw and develops a contact to the roof cladding. Overtime the corrosion progresses to cancerous state and penetrates the metal cladding allowing rainwater to ingress into ceiling space causing damage to timbers, plasterboard, insulation, electrical and even cabinetry or flooring below.
Its great practice to have your roof inspected annually if you are withing 1km of salt water or around every 5 years outwards of this. We have seen 3-year-old homes with corrosion bad enough to cause substantial internal damage and No, Insurance will not cover damages to your dwelling caused by a lack of maintenance. Regular Inspections will ensure that you keep on top of the problem to avoid your roofing iron from being affected by rusty screws. After all, replacing rusty screws is a lot cheaper than replacing roof sheets.
When engaging a building inspector for pre-purchase building inspection, make sure you are aware of the condition of the roofing screws, and keep in mind the corrosion process, because what might not be seen as a problem at the time of purchase can become a significant cost if not rectified. If you are made aware of any corrosion to metal roof fixings at the time of your pre purchase building inspection you will have the option of getting the screws replaced, which is a lot more cost effective than replacing the whole roof.
Contact us to find out more on roof corrosion and inspection processes.