CONSIDERATIONS WHEN APPLYING EXTERIOR PAINTS

 

Weather conditions should be taken into consideration when applying exterior paints as it may impact the overall finish of the job. The quality, continuity and uniformity of the film formed will be determined by temperature and drying conditions.

A.      Application and drying temperature:

  • If the temperature is too low, film-formation may not be optimum, resulting in compromise of film adhesion, toughness and longevity, and in some cases appearance including sub-standard gloss, colour and presence of cracks.
  • Air temperature should be no lower than the minimum application temperature require when applying paint.
  • Paint should only be applied if the surface is up to the minimum application temperature.
  • It is best to apply exterior paint when the air temperature is expected to stay at least as high as the recommended application temperature for the next 24 hours.

B.      Speed of drying:

To avoid compromising the durability and film formation, allow appropriate drying time. Having a combination of two or three of the following factors, may accelerate the drying time, which would hinder the durability of the paint:

  • Painting under very hot conditions: above 35 ° C
  • Painting in direct, bright sunshine, especially if the paint is of dark colour
  • The surface being painted is hot
  • The surface being painted is very porous
  • Conditions are breezy or windy
  • The humidity is very low (<20% relative humidity)

C.      Humidity and moisture:

  • Excessive moisture in the air can cause freshly applied paint to run, or dry slowly.
  • Do not apply paint if the air temperature is less than 3oC higher than the dew point; this is a better guideline than relying on relative humidity figures
  • Do not apply paint if there is evidence that moisture is forming on the surface to be painted or on nearby surfaces
  • Do not paint if the humidity is very high (>90%) and the temperature is predicted to drop

The information above is provided to assist our clients and is based on our experience in the paint industry. For further information, technical assistance or pricing please contact the Axolotl Paint sales team.