Winter foam – the construction foam for working in cold temperatures
What can you do, if the temperature on the building site drops below 5°C and conventional construction foam no longer works well? The solution for cold weather is winter foam.
Works up to -10°C.
This special foam is designed for temperatures of up to -10°C and can be used reliably on winter building sites. Winter foams remain flexible even at lower temperatures and do not become brittle like PU foams that are used when the weather is warmer.
Foams take longer to harden due to the reduced amount of humidity when temperatures are lower. In the case of summer foams, this could lead to a more coarse foam structure and impaired insulating values. Winter foams are optimised for these conditions and retain their properties in the cold.
Manufacturers also supply construction foam that can be used up to -20°C for countries with very cold winters.
Tip: Always check the temperature even of winter foam cans
However, like any other PU foam, when using winter foam, you should ensure that the cans themselves have a temperature of at least 5°C when they are used. Otherwise the fluid foam in the can will become too viscous and cannot be applied correctly.
When hard, construction foam is resistant to sub-zero temperatures
Once the construction foam has hardened, it is resistant to cold and temperatures of up to - 40°C. This also applies for ‘normal’ construction foam that is used in the summer.
And why does ‘normal’ foam not work in winter weather? In the cold, the moisture required for hardening is reduced and the chemical reactions are slower. This is why the foam cannot harden correctly. It can become brittle and crumbly, and form a powder-like foam structure.
Also, the colder the can is, the more viscous the PU prepolymer becomes. This is why the foam cannot exit the can valve as easily.
What you should do if you do not have any winter foam ...
and you need to use a normal PU foam can? In this case, you can warm the can carefully, for instance in a warm water bath; however, always be extremely careful to ensure that the compressed gas in the can does not expand too quickly. There is a risk of explosion, if the can heats up too quickly. Never place the construction foam can in hot water (above 50 °C) or heat with a flame!