Cold weather spray foam applications can prove to be very challenging. What works in the spring, summer and fall is twice as challenging when weather conditions are cold. Unless you are aware of problems that could arise and how to avoid them, trouble may follow.
Common Issues with Material Temperature
PROBLEM #1: The first thing to be aware of is that spray foam materials are temperature sensitive and become very viscous if allowed to get below 70 degrees. The Resin (“B” aka “R”) will be the first to show signs of cold weather effects. Having a thicker, stickier consistency than the Isocyanate (“A”) side at low temperatures, the R side greatly thickens to a point that it will not allow the transfer pumps to provide the positive pressure feed required at the proportioning unit, resulting in a cavitation.
At the spray gun, thicker Resin will be seen as intermittent/ pulsating shots of off-ratio foam, resulting in cross contamination and countless hours of lost production and product losses. Sounds expensive, right? It is. Having the means to maintain the temperatures within the manufactures recommended “in-container” temperature will minimize down time and keep those lost dollars in your pocket, along with the benefit of increased yield.
PROBLEM #2: Another thing to keep in mind, with cold weather setting in, is that any cold substrate with heat sump characteristics will cause a great deal of dense friable or brittle foam. What causes this is, the blowing agent that makes the foam rise or “blow”, boils at higher temperatures unable to be achieved once the warm liquids come in contact with a cold substrate. The higher temperature required to properly blow the foam is created by the chemical exotherm (heat generated by the chemical reaction) of the two reacting components. Where there is heat sump (a substrate that will absorb heat from the spray chemical), this heat is drawn off, not allowing the blowing agent to do its job. Consequently, the yield (board foot per pound of material) will be considerably reduced. Remember to follow manufactures recommended in-container temperature, environmental conditions, proper installation techniques. Additionally, when attempting to control the environmental conditions remember to not heat with hazardous fuel sources and utilize safe handling procedures for fire and health safety.
The Solution is Not-so-Difficult
When the material temperature is within manufacturer specified range, yield is increased and the components of material mix at an appropriate rate – preventing poor application.
A proven solution is utilizing a drum heating system to safely provide a cost-effective means of consistently heating your products from the bottom of the drum where your transfer pump is removing the material. Unlike some cheaper options, like heating bands, which are satisfactory for quickly applying heat to cold materials. Heating bands also require frequent monitoring and expose materials to scorching temperatures.
Interested in learning more about spray foam? Visit our blog or website or contact the professionals at SprayWorks Equipment Group.