Mixing your own custom white paint is probably the closest thing there is to a “secret” for creating beautiful interiors. The lavender-toned wall in the kitchen photo is a premixed white Benjamin Moore paint, while the true white on the ceiling and on the walls outside the kitchen is a custom white.

The premixed whites that are sold in your paint store are not true whites. This is because of a few optical illusions that affect how our eyes perceive white paint.

Do I need a cool or warm white paint?

The short answer is that you need a white paint that is both cool and warm. Cool whites and warm whites create different optical illusions.

• Blue or grey tones – A white paint with blue or grey tones will look dark and dirty if you look at it around sunrise or sunset. These cool-toned whites will create a commercial aura in your home, that while appropriate for an art gallery, may make you feel as if you’re living in a concrete bunker.

• Yellow or cream tones – A white paint with yellow or cream tones will look aged and dingy if you look at it around sunrise or sunset. These warm-toned whites are popular in older homes in sun-drenched locales, but shouldn’t be used to coat your walls from floor to ceiling unless you live on a beach or mountain top.

How do I pick the right shade of white paint?

The shade of white that you need depends on the amount of light that a room gets throughout the day, both from daylight and from interior lighting.

• Room size – The larger the space, the lighter a paint colour will appear to be. Conversely, the smaller the space, the darker a paint colour will appear to be. As a rule of thumb, if you’re painting a small space, you’ll need to opt for colours that are a shade lighter than how you want the finished room to appear.

• Lighting – If you have lights that are blue-ish or yellow-ish, that will also affect the appearance of the paint colour you choose. Before painting, be sure to install your light bulbs, otherwise you may find the colour of your home changes entirely after you’ve already painted.

Custom white paint is perfect for your interior walls

You’ll want to find paint chips for both a warm white and a cool white and place them side-by-side on your wall for 24 hours of observation. Pick the two colours that appear to be the whitest at all hours of the day, one warm white and one cool white.

The best white paints will seem like they almost glow in the dark when the sun goes down. Your local paint store will be able to create a custom white that’s 50% the warm white and 50% the cool white that you choose.

When looking at the kitchen in the photo, you’ll notice that the custom white or true white paint, seems so much whiter to the eye than the lavender-toned, premixed white paint.

Find more resources for interior painting here.