Maximising daylight in design

Daylight, our most vital resource has been illuminating our planet for over 4 billion years and yet we still do not make full use of its benefits. Sunlight drives our very existence and without it we would not survive. So why don’t we use it more? No matter where we are, we always try to find the best spot to relax, usually in the sun. Even at the end of the day with the sun going down, light stirs emotions within us. So let’s bring the outside inside.

Daylight has been used for centuries as the primary source of lighting interiors and has been an implicit part of architecture for as long as buildings have existed. Not only do you need to consider how and where daylight enters, but also just as important are the internal finishes. Bright walls, ceilings and floors can bounce and reflect daylight into areas that would normally be quite dark.

With careful play of the daylight you can highlight certain features within the home. Or you can draw light through into spaces that would otherwise need artificial light to be used effectively to create calming and tranquil areas to just sit and relax or create dramatic scenes and illusions of greater space.

There are so many ways of maximising daylight, from every facet of the envelope of the building. But each method of bringing in light creates a very different ambience, so consider this carefully when planning your home. The desired spread of light will have an influence on where windows are positioned and also on the size of windows. Therefore, consider the distribution of light within a room when selecting the number and size of windows. However, increasing the spread of light does not necessarily mean improved daylight factors and it is important to ensure that you get the right balance between light intensity and light coverage.


The daylight factor is quite simply the ratio of light that hits the roof of a house, compared with the amount that actually hits a surface 850mm above the floor in the room, represented as a percentage.

The example shown below is based on roof windows with a daylight area of just 1.41m2 distributed from either one, two or four windows. The amount of glazed area remains the same but the spread of light is quite different:


The roof pitch is 45° and the room measures 6m x 6m:

But when comparing average daylight factors, these diminish when using more and smaller windows:

Positioning of windows is therefore extremely important to achieve the optimum daylight levels and effects.

There are many tricks you can use to maximise the light once it is inside the house. For example, use high level windows to provide natural daylight into the rear of the home where use of vertical windows might not be possible due to adjacent buildings. And with clever use of internal glazing or translucent materials, light can then travel further into the house.

However, the more daylight you bring in the greater the need to control it, so ensure that you consider how you can alter it to suit your needs.

Decorative blinds, curtains and different glazing options can produce pleasing results if done in the right fashion.

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