Choosing the right colour of paint for a room could have a great impact not only on people’s moods but on their electricity bills as well.

It is no secret that lighter colours reflect more light and absorb less heat while dark colours absorb both light and heat. As a result, a room with light colour walls will need less artificial lighting than a room with dark coloured walls. In order to strike the right balance throughout both warm and the cold seasons, it is beneficial to use light colours for walls and dark colours for furniture.

Light colours reflect more light

Light colours reflect more light and absorb less heat.

Light coloured walls are ideal for creating an electricity efficient home. They are less heat absorbent, so they stay cooler during summer months, which cuts down on air conditioning costs. During the winter, meanwhile, they do not take up much of the heat generated inside the room. In addition, painting the ceiling a light colour allows it to reflect light much better.

Most paints on the market are labelled with a Light Reflectance Value (LRV) corresponding with their colour. The higher the LRV number, the less the need for artificial light. For example, white reflects 80 per cent of light while black only reflects five per cent.

Warm colours

Warm colours such as orange, yellow and red can make people think the temperature in a room is six to 10 degrees Fahrenheit warmer than it actually is.

Using white paint has many benefits; it is less expensive, it goes with virtually all furniture, and it makes a room look larger and brighter. During daylight hours, a home with white walls can rely purely on natural light to brighten a room.

However, when an overabundance of light is combined with very light walls, it may create glare or even excess brightness, overstimulating and even irritating eyes, leading to eye fatigue. To achieve a proper balance, painting some walls in warm colours or adding warm-coloured furniture are simple solutions.

cool colors

According to studies, people felt a room with cool colours such as blue or green was cooler than it actually was.

From a psychological standpoint, colour greatly influences human emotions and behaviour. Recent studies have shown that the colour of a room can affect people’s perception of temperature. The studies showed that people estimated the temperature of a room with cool colours such as blue or green to be between six and 10 degrees Fahrenheit cooler than the real temperature. Warm colours such as orange, yellow and red led people to believe the temperature in the room was six to 10 degrees Fahrenheit warmer than it actually was.

The higher the LRV number of the paint colour

The higher the LRV number of a paint colour, the less artificial light you will need.

The relationship between the coating on a ceiling’s surface and the amount of light that is distributed throughout the room is also strong. Though ceiling paints commonly tend to be lower-quality than wall paints, it is important that they have strong pigments, which are necessary in order to reflect light and not fade out in a short period of time.

As dark colours absorb more heat than light colours, a dark ceiling will absorb light. Trying to overcome this light absorption through more or stronger artificial lighting can be expensive.

very bright walls

An overabundance of light combined with very light-coloured walls may create glare and/or too much brightness.

  • One of my favourite parts of Environmentally Sustainable Design is the advising on colour selection. It’s an interesting field because a little bit of thought can make a significant yet cost-effective contribution to building design.
    I’ve also been involved in selling non-toxic paints for the past twenty years. The colour ranges of non-toxic paints are more limited (because the paint colours can be the most toxic component and/or there could be issues in sourcing the raw ingredients) but fortunately the colours available are also the colours are in demand.
    Incidentally, externally, colour and vegetation are also very important in the temperature moderation of buildings. Generally use light colours on external walls and roofs.