9 tips for how to achieve high-quality results with polyurethane foam

Occasionally, cold starts to enter through sealed joints sometime after the window or door installation. Have you ever considered why this might happen?

Often, professionals want to perform the work faster, occasionally leading to poor end results. Penosil experts have prepared nine tips that, if followed correctly, allow you to achieve a higher-quality and long-lasting result when building with construction foams. 

1. Aerosol can temperature matters! 
   You can find the correct aerosol can temperature information on the product’s label or on penosil.com/us webpage. Knowing the correct can temperature is especially important during winter. If the aerosol can is too cold, it must be brought to the right temperature by storing it in a warm room or placing it under warm water. Be careful also when working at very hot temperatures. Aerosol can’s temperature should never exceed the recommended 86˚F. If the can is warmer than 86˚F, store it in a cool place for a while or pass it under cold water to cool it down.

2. Storing and transporting. 
   Foam can should always be stored in an upright position. Storing the can correctly protects the can valve from clogging and allows the foam to be applied evenly. Foam can must always be protected from direct sunlight and stored at temperatures between +40°C to +86˚F.The aerosol can should never be exposed to temperatures over +120°F or kept near heat sources.

3. Preparing the surfaces.
   Before applying the foam, ensure that the surfaces to be sealed are clean from dust, loose particles, ice and oil stains. Clean surfaces ensure that the polyurethane foam has stronger adhesion with adjacent surfaces.

4. Humidity is important.
   Most PU foams require humidity for curing. Therefore, additional moistening is needed for almost all Penosil polyurethane foams. Moistening dry surfaces with water mist ensures faster curing time, better foam structure and better overall results. In case of larger joints, apply foam in several layers and moisten slightly between each layer. Usually, no additional moistening is required during winter because the air humidity is naturally higher.

5. How to use gun foam?  
   Shake the can vigorously at least 20 times. Hold the foam can in an upright position with the valve up. Screw the can to the gun. Hold the can upside down when extruding the foam. Foam output can be adjusted with a gun trigger and adjustment screw. As the foam expands, joints should never be fully filled with foam. You can find the information about the correct filling level on the product’s label or on penosil.com webpage. Do not aim the gun at people. Avoid screwing the can to the gun with the valve upside down. Do not screw the gun to the can. Do not bend or turn the can during screwing.

6. How to use straw foam? 
   Shake the can vigorously at least 20 times. Remove the cap. Hold the foam can in an upright position with the valve up. Screw the straw applicator tightly to the foam can valve. Hold the can upside down when extruding the foam. Foam output can be adjusted with the applicator trigger. As the foam expands, joints should never be fully filled with foam. You can find the information about the correct filling level on the product’s label or on penosil.com webpage.

7. Curing process. 
   Do not cover the foam during the curing process. It needs air humidity to expand, fully cure and form a correct foam structure.

8. Be patient – do not cut too early! 
   Excess foam can be cut with a knife after it has fully cured. Cutting a fully cured foam does not damage its mechanical properties. However, if you cut the foam too early, its structure will be damaged, and it will not form an airtight and soundproof seal. The longer you wait, the better it is.

9. UV protection. 
   Polyurethane foams are sensitive to UV rays. Prolonged exposure to UV rays will damage foam’s properties. Therefore, after the foam is fully cured, it is recommended to cover it with a suitable opaque material such as paint, sealant, window strips etc.

Following the recommendations above enables you to achieve higher-quality work and enjoy the results for many years to come. Check out also our other educational articles in Knowledge Centre.