How Winterization Effects Epoxy
Half of the country is in the throes of the first winter weeks and the epoxy and building industry is coming upon it’s traditional slow season with outdoor projects being delayed between December and April. This decrease is due to the substantial impact that temperature has on epoxy installation due to its chemical makeup and potential reactions that occur at respective temperatures. These reactions are subject to both the ground temperature and the air temperature.
A standard epoxy has a benchmark of 55 degrees to kick off a a chemical reaction – called an exothermic reaction – that releases heat. While warmer temperatures acerbate this reaction, colder temperatures decelerate exothermic reactions and molecule cross-linking is reduced, thereby decreasing the dependable strength of the bonds. Complications of winterization of epoxy installations include epoxy that:
- must cure for a longer period to achieve the desired cross-linking (i.e. bonding);
- fails to achieve optimal properties despite eventual completion of hardening if the temperature is too low;
- has increased flexibility significantly decreasing the epoxy’s tolerance of repeated fatigue or creep ruptures.
Our decades of epoxy experience have allowed us to cultivate expertise on epoxy’s performance throughout a wide variety of conditions – including winterization. Though we see a slow down in flooring installation during winter, there are occasional projects that come online or repairs that demand immediate attention. So can you complete your epoxy installation during the winter months? Obviously, during winter months, epoxy installers don’t have the benefit of mild temperature and though we always prefer installations under ideal conditions, there are adjustments that can facilitate epoxy installations in a winter climate.
One adjustment is to manipulate the epoxy itself, formulating a solution which cures in less than ideal conditions. This formulation will utilize a unique combination designed to enhance epoxy performance at temperature variances under the benchmark of 55 degrees (as low as 30 degrees). Hardeners – like poly aspartic flake – from the polyuria family – can be added to augment cold weather epoxy projects. Its gelatinous texture offers greater chemical resistance, curing harder than traditional epoxies. It is more expensive but has much higher temperature resistance. However, chemical manipulation to enhance hardening properties will not guarantee that you will get dependable bonds in cold weather and dependable bonds are what gives epoxy its strength. Other factors that impact bonding in cold weather include floor and ambient air temperatures.
Epoxy immediately mirrors the temperature of any substance on which it is applied. Therefore, the floor temperature is of paramount importance. In cold weather, concrete is typically cooler than the ambient air temperature. Both the floor and the ambient temperature must be higher than 55 degrees for 100 percent solid epoxies to harden with a chemical reaction that maximizes strength, hardness and longevity. Any colder and the solution will stay “soupy” and fail to harden or – hardens less quickly and risks underperformance, cracking, peeling and bubbling. Propane heaters can be used to heat the ambient air in smaller spaces; however this process takes days. Heat guns or heating blankets have proven to work well, but if the floor temperature is too low and the project can be delayed, it should be to lower costs and increase the efficacy of the installation. Ambient temperature similarly effects the rate and degree of epoxy cure. Temperature can impact epoxy resin by changing it’s viscosity, which can thicken drastically – impacting flow – in colder temperatures. This causes:
- increased possibility of deficient bonding due to difficulty in mixing resin and hardeners and inaccurate proportions;
- difficulty in applying epoxy mixture due to lack of viscosity – or flow – which can result in uneven, thick epoxy coats requiring extra sanding;
- epoxy that is too thick to penetrate porous surfaces;
- air bubbles to form and become trapped in thicker epoxy decreasing the bond’s strength and ability to repeal moisture.
If the resin and hardener are not mixed well, disregarding either the ratio of resin:hardener, or not mixing the material a long enough period, then the resin will remain in a sticky or soft state for longer than needed, allowing dust and damage to be done.To mitigate these complications, epoxy liquids should be stored at room temperature 70-78 degrees) for 12 to 24 hours before use. Liquids can be placed into a warm water bath to bring their temperature up. It’s also imperative to have a team of experts, like REDRHINO’s Because application and cure time is longer, mixing, spreading and curing require additional time offline and without foot traffic.
Another winter complication is moisture, which is prevalent in winter air as mist, snow or runoff water. If this moisture seeps into concrete or is present in the air, the epoxy installation could fail. Moisture tests are run and if detected, the concrete is ground with 800-pound grinders to expose the pores in the concrete creating capillaries allowing the trapped moisture to come to the surface. If the moisture amount is still too high, a vapor barrier will be laid to seal the moisture in to prevent it from coming up to the surface. Similarly, if the surface is not dry, or if there is a pipe dripping, it will severely devastate the epoxy. RED RHINO checks and double checks humidity levels, making adjustments based on the levels. Epoxy should not be applied in environments with <85 percent humidity, projects scheduled with humidity levels this high should be rescheduled.
It’s important to understand potential consequences of winterized projects and to know that longer completion rates and higher expenses might be a reality. Having an expert team, like REDRHINO specialists can mitigate some effects of colder temperatures to proceed with winter flooring installations.