Technical Guides

#6 Heat & Coatings Do Not Mix


Time of the year: December – March (or really hot days, or direct sunlight)

All coatings performance and drying times are influenced by both temperatures and humidity. This can create major challenges when trying to coat a floor if the conditions are too hot. This can either be when the general temperatures are higher, or the actual floor surface itself is too hot. This can be from the current environment, direct sunlight or the flooring being exposed from the underside. Careful consideration when coating a floor should be taken to avoid possible issues.

What are the problems if it is too hot?

  • Faster drying time resulting in varying gloss levels
  • Orange peel look on the surface (see image)
  • Lap marks from decreased flow (see image)
  • Air bubbles (see image)
  • Coating going off in the container
  • Coating ‘frying’
  • Picture Framing
  • Coating viscosity can change resulting in percolation (soaking/filtering into timber)
To fix almost all of these problems it would require a full costly re-sand as well as loss of time.

There are many things that can be done to avoid these issues;

  • Use wet edge extender for temperatures generally over 25 degrees (check individual product guides to be sure)
  • Don’t leave containers in a hot van for longer than needed
  • Be careful not to cut in too far ahead of roller
  • Close blinds where possible to avoid direct sunlight
  • Keep consistent with required coverage rates of products. Simply applying a thicker coat to avoid it drying out too fast can also create further drying issues
  • More careful feathering of coating on edges

Ultimately the best way to avoid these types of issues or having to use a wet edge extender is to monitor predicted temperatures for the job ahead and plan the jobs and sanding time so that coating times will not be during the hottest part of the day (or even just prior to the hottest part of the day). This could mean coating much later in the afternoon on a job that is expected to get far too hot.

For all products it is always recommended to check the individual product data sheets for optimum temperatures as well as other recommendations to ensure you get the best result.

If you require any clarification on anything or for any further questions please contact the team at Marques Flooring.