General Paint Colour School: Lesson 4 – Colour and Intensity


The word intensity or saturation quantifies the purity and brightness of a colour. At maximum intensity a colour is fresh and vivid.

Low-intensity colours are by comparison quiet and subdued. They have been “knocked back”* by the addition of a muted hue to create more subtle effects. For example you can inject vitality into a room scheme by introducing a slightly brighter yellow among muted yellows.

Intensity is often confused with value, which signals the lightness or darkness of a colour. A pea colour is a light value of green, while navy is a dark value of blue.

Harnessing these qualities is vital to the success of a colour scheme. You can use similar intensities and values to link different colours. Bright with bright, subdued with subdued; light with light, dark with dark.

But a uniform approach is not always desirable, so spice up a scheme dominated by light values with a few dark accents.

* In the colour business we call them clean and dirty colours but in the paint business it is better to say bright and neutral as most people don’t want to paint their walls with a dirty colour. It is called dirty as black is usually added to “knock it back” or tone it down.



Ask an Expert

Q: Why is the exterior paint on my wall bubbling and then lifting off? And what do I do now?

A: Excellent question and this can happen from time to time. But there are reasons why and it can be fi xed. First off, when this happens, we in the biz call it blistering.


Bubbles resulting from localized loss of adhesion, and lifting of the paint fi lm from the underlying surface.


  • Painting a warm surface in direct sunlight.
  • Application of solvent-based paint over a damp or wet surface.
  • Moisture escaping through the exterior walls (less likely with water-based paint than with solvent-based).
  • Exposure of water-based paint fi lm to dew, high humidity or rain shortly after paint has dried, especially if there was inadequate surface preparation.
  • Multi coat blistering usually occurs when acrylic paints are applied over many layers of alkyd and acrylic paints; often when darker colours are used causing heat build up.

What are the SOLUTIONS?

  • If blisters go down to the substrate: try to remove the source of moisture. Repair loose sealants; consider installing vents or exhaust fans. Remove blisters (see below).
  • If blisters do not go all the way down to the substrate: remove them by scraping, then sanding, prime bare wood and repaint with a quality water-based exterior paint.

Information taken from the PQI (Paint Quality Institute)



Speak Your Mind