Winter can be a challenging time for many construction projects, particularly those that require the use of adhesives and basecoats. The lower temperatures can significantly slow down the drying and curing process, leading to delays and potentially compromising the quality of the final result. That’s why EWI Pro’s EWI-221 Winter Adhesive is an essential product for your winter construction needs. It’s specially formulated to combat the challenges posed by cold weather, ensuring your projects proceed smoothly even when the mercury drops.

Why does lower temperature affect drying and curing?

1. Rate of evaporation

Evaporation is an endothermic process, meaning it requires heat energy to transform solvents from liquid to gas. In colder conditions, there is less ambient thermal energy available to facilitate this change. Therefore, solvents in your basecoat or adhesive evaporate more slowly, extending the drying time. This slower evaporation can be particularly problematic when you’re on a tight schedule.

2. Chemical reactions

The curing process often relies on chemical reactions that are exothermic, meaning they release heat. However, for these reactions to initiate and proceed efficiently, they require certain activation energy. Colder temperatures mean that molecules have less kinetic energy, making it harder to reach the activation energy needed for these reactions to occur. As a result, curing is delayed.

3. Viscosity

Temperature and viscosity are inversely related for most materials. As temperature decreases, the viscosity of your basecoat or adhesive increases. A thicker, more viscous material has less surface area exposed to the air, which in turn slows down the rate of solvent evaporation and makes application more challenging.

4. Humidity interactions

Lower temperatures also influence the moisture-holding capacity of air. Cold air can hold less moisture, meaning that if the air is near its maximum moisture-holding capacity, the rate of solvent evaporation will further decrease. Additionally, high relative humidity can create a barrier of moisture-laden air around the drying surface, making it harder for solvents to evaporate.

5. Air circulation

Cold air is denser and less prone to natural convection currents. Reduced air circulation inhibits the dispersal of solvent vapours away from the adhesive or basecoat surface. Slower dispersal can contribute to longer drying times and may also pose safety risks if volatile organic compounds (VOCs) are involved.

6. Material properties

The properties of the substrate material itself can also be affected by low temperatures. For example, materials like concrete or wood may be less porous at lower temperatures, reducing their ability to absorb the adhesive or basecoat. This can lead to longer drying times and may also impact the quality of adhesion.

7. Energy transfer

In thermodynamics, the rate of any process, including drying and curing, is often dictated by the rate of energy transfer. Higher temperatures speed up energy transfer due to increased molecular motion, making processes like drying and curing more efficient. In contrast, lower temperatures slow down this energy transfer, delaying these processes.

Why do you need Winter Adhesive then?

Winter Adhesive is specially designed to combat the problems with EWI projects in colder weather. Special additives, including microfibers, impact the frost-proofing and flexibility.

Ideal for low temperatures

Unlike standard adhesives that can struggle in colder climates, EWi-221 is specifically formulated to perform optimally even in temperatures as low as 0°C. Its exceptional frost-proofing capabilities ensure that your project won’t grind to a halt when the weather turns icy.

Versatile usage

This adhesive serves dual purposes: it can be used both as a reinforcement basecoat layer and for affixing expanded polystyrene (EPS) insulation boards to various substrates. This means you don’t need to switch between different products, simplifying your workflow.

Quick setting even in the cold

The inclusion of microfibres in its formulation ensures that EWI-221 sets in a timely manner, even at lower temperatures. This allows you to maintain a continuous workflow, saving both time and resources in conditions that would normally be prohibitive for construction.

High-grip and flexible

EWI-221 boasts a superior grip, ensuring that EPS boards adhere securely to substrates. The microfibres also add an element of flexibility to the adhesive, reducing the risk of cracking or other structural issues.

Waterproof and hydrophobic

Another standout feature of EWI-221 is its hydrophobic and waterproof properties. This is crucial for external wall insulation systems, as it offers an added layer of protection against moisture damage, thereby extending the lifespan of your project.

Ease of preparation

Whether you’re using it as a reinforcement basecoat or for attaching EPS boards, EWI-221 is prepared in the same straightforward manner. This uniformity in preparation further streamlines the construction process, allowing for more efficient use of time and resources.

Limitations

It’s worth noting that EWI-221 is not recommended for fixing extruded polystyrene (XPS) or for use on bituminous substrates. Make sure to choose the right adhesive for those specific applications.