If your in this kind of business then you should know how important it is to give a coat of paint to the cladding sheets during their manufacturing process. This prevents the sheets from getting damaged from the elements of nature. But when you cut the sheets to suit your needs, you may not be recoating the edges. This small neglect may leave a major chink, leaving the cladding sheets exposed to the risks of corrosion. If this goes unchecked and unheeded, you may have to change the cladding soon rather too soon.
Cut edge corrosion
Though the quality of coating meant for metal sheets has improved significantly in recent times, corrosion and deterioration due to the delamination of coating is a constant threat. This seriously compromises the roof structure and performance. There are at least two vulnerable sections in the cladding sheets that can develop corrosion: Cut edge and overlapping joints.
The cut edge corrosion begins when water is not able to run off completely. In a typical rainy season, a tiny amount of water often builds up on the edges of the metal sheets and seeps into the protective layer made of zinc. After some time, the water is able to dissolve the zinc and remove the protective coating (PVC/PVF2). The corrosion begins to eat into the iron sheet and if ignored, it progresses from the cut edge to a major part of the metal sheets.
When the corrosion begins to take the sheets into its destructive stride, it first destroys the cover-up joint and gutter overhang. Before you could realise that the quality of your roof is getting tampered with, you are already saddled with some expensive sheet repairs. It will not take long for the roof to start showing corrosion lines along the joints and the whole roof to show rust stains all over it.
There are some standard treatment methods that contractors use across the board for rusting metal sheet roofs. High-quality coatings that offer effective control of roof
corrosion are available from reputed brands. The contractors use these coatings and available techniques to apply a new anti corrosive coating on the damaged and rust-affected portions of the metal sheet roofs. As a result of the re-coat, your building once again becomes fully waterproof.
There are two major techniques to protect the metal roof edge from corrosion: Seamsil and Cladspray solutions.
Seamsil is another very efficient method to treat the corroding cut metal edges. It’s a long term solution that protects the overlap joints. Seamsil is a silicone-based treatment that aims to restore and augment the original level metal sheet protection. It is an effective formulation to treat rust. Seamsil also tends to fix chemical corrosion and industrial pollution at metal cut edges. Considered fit for coastal and marine environments, it completely stops the deterioration of lap joints by effectively stopping the inflow of water. Seamsil provides the most effective protection against any kind of cut edge rusting.
Cladspray solutions are applied to the cut edges of the metal sheets. The process involves removing rust and corrosion mechanically and then applying recoats on the corroded edge laps. After filling up the damaged portions with a re-coat, a fresh coat of anticorrosion is applied, followed by another waterproof coating.
Cut edge corrosion is as common as not giving it a coat when the sheets are being used in cladding. However, there are ways and treatments that can restore corroded metal sheets and prevent them from further corrosion.