Posted on: 24 October 2016Share
When you install a metal roof on your house, you must coat and shield it from the corrosive elements that gradually choke it to death. Lack of a protective coating shortens the life of your roof, forcing you into high replacements costs. Notably, the secret to choosing a quality water-based acrylic coating is to understand its chemical components. What exactly do they bring to the table to guarantee that your roof will be in place for many years? Here are some of the chemical additives that you should look out for when buying a water-based acrylic coating for your metal roof:
Surfactants and Dispersants
Surfactants and dispersants are like pepper and salt additives, giving an x-factor to your water-based acrylic coating after it has been applied. They are a mixture of solvents and emulsifiers, which help to break down the oil in the acrylic coating. By doing so, the surfactants and dispersants improve the uniformity and ease with which the coating is applied on the surface of the roof. They stabilise the coating such that the blend remains uniform for consistent and efficient application on the metal surface. To add on that, they improve the water resistance of the roof and help to reduce the build-up of mould and mildew. This is important for roof sections that spend lots of time covered by shade from nearby trees.
Defoamers help you deal with air entrapment issues when you are applying the coating on the roof. Basically, acrylic water-based coatings are thicker (more viscous) than ordinary paints. Moreover, they are applied in thicker layers regular paints due to the harsh conditions that roofs expose them to. All these factors (viscosity and thick layers) encourage air entrapment when you are applying the coating on the roof. The entrapped air is a cause for concern because it creates lines of weakness within the coating film. Therefore, look out for defoamers on the coating's packaging to guarantee good performance from the membrane.
Does your roof have steep and vertically inclined sections that are generally challenging to coat? Well, you can go for a water-based acrylic coating with thickeners to provide resistance to sagging. Thickeners ensure that the coating cures properly by proving the appropriate rheology. Preferably, an acrylic coating with thickeners should have dispersants and surfactants for ease of application. Note that various manufacturers use different additives in their products, and an understanding of the things discussed here will help you when selecting what's best for your roof.