Silicone roof coatings are a popular choice for many commercial buildings. They provide protection against the elements, UV rays, water damage, and more, and are a cost-effective alternative to roof replacement. As with any type of coating, they do have a limit to their lifespan, and this can be affected by a variety of factors. These include the quality of the silicone, the climate, the installation technique, and the level of maintenance.
Silicone coatings are single-layer roof coatings made from silicone. Their main component is silicone polymers, a synthetic material derived from silicon, oxygen, carbon, and hydrogen. The key ingredient is siloxane, which gives silicone roof coatings their waterproofing and flexibility.
To enhance the performance of the silicone, other additives include:
There are some key advantages of silicone roof coatings that make them an ideal choice for protecting a commercial roof.
Over time, UV rays contribute to the degradation of roofing material. A silicone roof coating has reflective properties that bounce UV rays away from the roof, rather than absorbing them into the materials.
One of the most harmful factors affecting roofs is water damage. Moisture can cause structural damage over time, and it can be difficult to protect roofs entirely from it, especially when there are harsh weather conditions.
A silicone coating has hydrophobic qualities. This means that water cannot get past the roof surface, and instead runs straight off.
Read our post "Can you make roof tiles waterproof".
High-solids silicone roof coatings provide extra durability compared to other coatings like acrylic. Silicone roof coatings usually have a solids content that is over 90%. This means that after the coating is applied and dries, a large portion of it remains on the surface. The result is a thicker, more protective layer, even after a single application.
In contrast, acrylic roof coatings have a lower solids content and rely more on water and other solvents that evaporate after they dry. This results in a thin layer remaining on the roof, rather than thick. To achieve the same thickness as a single layer of silicone, acrylic coatings will require more coats.
Check out our post “How long does acrylic roof coating last”.
A silicone coating can help to reduce your energy costs, by preventing the heat from the sun from warming the building. This means that you won't have to use as much energy to cool it.
A silicone roof coating lasts between 15 and 20 years, and sometimes even longer. The average lifespan of a standard roof is anywhere from 20 to 50 years, so an additional decade or more can have a significant impact.
As we have discussed, the best silicone roof coating system may differ slightly in its composition and additives. To get the best-expected lifespan, you should seek advice from your roofing company about the highest quality silicone roof coating available.
There are several factors that can impact the longevity of a silicone roof coating.
The condition of the existing roof can alter the lifespan of any roof coating you apply. For example, if there is any roof damage such as cracks or holes, water can seep through which can cause the coating to fail or bubble.
In a similar way, anything that affects the roof's structural integrity can shorten the lifespan of a silicone roof coating. If the roof is too old or weak, there will be more frequent flexing or movement, which can put added stress on the coating materials, causing them to fail.
A flat roof or a roof with poor drainage can experience "ponding water". This is when water pools in certain areas rather than draining off. A silicone roof coating is more resistant to ponding water than an acrylic roof coating, but prolonged exposure can still cause some localised weakening.
If the roof has previously had a roof coating applied, its compatibility with the silicone roof coating will make a big difference to its longevity. If the materials are not compatible, this can result in adhesion problems or bubbles forming. If the old coating peels or lifts, it can take the new silicone coating with it.
In some cases, older roof coatings will need to be removed before a silicone roof coating is applied. In other cases, a primer will be needed before application.
Arguably the biggest factor that impacts the lifespan of a silicone roof coating is whether or not it has been applied correctly.
A clean roof surface is important for a silicone roof coating to adhere properly. Any contaminants such as debris, dirt, mildew, or oil can prevent the silicone from sticking to the surface, leading to peeling, lifting, or bubbling.
If there is damage, it needs to be repaired before the roof is coated, and the roof also needs to be dry. Water on the surface can lead to water entrapment beneath the coating, which can prevent the coating from sticking to the surface.
The lifespan of a silicone roof coating is highly dependent on its thickness. Most manufacturers recommend a thickness between 20 and 30 mils. Applying the coating too thinly will reduce its protective capabilities, and make it more susceptible to wear and UV degradation.
Hiring professional roofing contractors with experience working with silicone roof coatings is often well worth the investment. They will have specialised knowledge about the best application techniques and can modify their work to suit different conditions and roof types.
They will also use professional tools, equipment, and products that make a smooth, even, and thick application more likely.
Once your silicone roof coating has been applied, you can extend its lifespan through consistent maintenance, cleaning, and repair.
Regular cleaning of your silicone roof coating is an important part of its maintenance. You should pay particular attention to removing debris, especially around drains and gutters, and removing moss. These issues can trap moisture, which can eventually degrade the roof coating.
You should inspect your silicone roof coating semi-regularly. Aim for at least once a year, plus an inspection after any extreme weather conditions. This will help you to spot any emerging issues that can be dealt with before they become more major.
If you do notice any issues with the silicone coating, you should get it repaired as soon as possible. A small crack will get bigger over time and become a more expensive and time-consuming problem to fix.
If you want to protect your commercial roof from damage with a silicone roof coating, we can help. Our professional installation service ensures that your coating is applied with precision and expertise, which will maximise its lifespan and save you the cost and hassle of frequent repairs, or even a full roof replacement.
Our experienced team of technicians will inspect your roof thoroughly to check for any underlying issues and the compatibility of any existing roof coating, and will prepare the surface before installing the silicone with professional attention to detail.
A silicone roof coating is a popular choice for UK building owners. With our variable and wet weather conditions, roofs are at risk of water and UV radiation damage. Silicone roof coatings protect your roof from these issues, and will last 15-20 years, so are a worthwhile and cost-effective investment. Especially in comparison to a full roof replacement.
