Windows and natural light

Posted on 02 March 2008 2 comments

“Windows need to provide light, insulation, ventilation and security, but they are also the ‘eyes’ of a building, playing a key role in the design of its facades.”
From ‘Exploring Architecture’ by Eleanor Gawne and Michael Snodin (V&A Publications, 2004)
“The window can be said to be the most important architectural feature of a building; this is the first experience that a visitor will have when seeing the building for the first time, and architects have naturally considered the form of the window and its relationship to the exterior to be vital.”
From ‘Daylighting: Natural Light in Architecture’ by Derek Phillips (Architectural Press, 2004)

Natural light is immensely important in our homes. It sounds so obvious, it hardly seems worth stating. But just take a look at the front of this new build Barratt house:

New build house with tiny windows

If windows are indeed the ‘eyes’ of a house, this one is practically squinting! (I wonder why the larger windows in the house are perfectly square? It gives a very bland and uninviting appearance to the building.)

To be fair, there are many factors that influence the position, size and shape of windows. Outward appearances can be deceptive – windows don’t have to be huge to illuminate a room in a pleasant way. Housebuilders have to meet minimum standards for energy efficiency and ordinary double-glazed windows can be a significant source of heat loss. The easiest thing to do is simply reduce window size and coverage. And let’s not forget that the size of windows in many new builds probably reflects their miserly room proportions!

The practice of using natural light to illuminate buildings is known as daylighting. Why is it so important? Author Derek Phillips in his book Daylighting: Natural Light in Architecture, says it’s because of:

“the subconscious desire of people when inside a building to keep in touch with the outside world, whether to know the time of day or the nature of the weather.”

What’s more, natural light is a benchmark for how we perceive the colour of our surroundings:

“Whilst the colour of daylight will vary from morning to evening, and with changes in the sky and weather patterns; it is always regarded as ‘real colour’.”

Natural light can transform a living space and can even affect our wellbeing, but it’s not simply a question of placing the largest window possible in every room. Natural light can be used to create many different effects – think of the way light shines through clerestory windows. Or how sunlight filtered through the branches of a tree outside a window can throw a beautiful dappled pattern of light across an interior wall. These are the sorts of things that housebuilders should be thinking about when they design homes. I wonder if they do?

The architect Colin St John Wilson, who designed the British Library, had this to say about natural light in the design of the Library:

“Daylight is introduced as the principal source of ambient light, its properties of vividness and variation are a sense of stimulation that no artificial lighting system can emulate and they bring to the reader the further stimulus of an awareness of the natural rhythms of the day and season – the passage of the sun and the shifts in the weather – a rewarding relief from sustained concentration on a close task.”
From “The Design and Construction of the British Library”, British Library Publishing Division, 1998

Christopher Alexander in his book, A Pattern Language, believes there should be light on two sides of every room (pattern 159):

“When they have a choice, people will always gravitate to those rooms which have light on two sides and leave the rooms which are lit only from one side unused and empty…

This pattern, perhaps more than any other single pattern determines the success or failure of a room. The arrangement of daylight in a room and the presence of windows on two sides is fundamental.”

This advice isn’t much use if you live in a block of flats or terraced house. What’s more, detached or semi-detached houses may be affected by shadows cast by neighbouring properties depending on how sufficiently spaced apart the homes are. So, however desirable the presence of windows on two sides of a room, the practicality seems unrealistic. Alexander goes on to say:

“…sometimes it is just impossible…the rooms can get the effect…if the room is very shallow – no more than eight feet deep with at least two windows side by side. The light bounces off the back wall and bounces sideways between the two windows so the light still has the glare-free character of light on two sides.”

The trouble is that 8 feet (2.4 metres) really is too shallow for many types of rooms.


I don’t think many of us need convincing of the importance of natural light in a home. So it begs the question why modern homes are so badly designed in this regard. I’ve written before about how much I dislike windowless bathrooms and windowless kitchens. I wish this practice was regarded as unacceptably poor design, but in fact it’s become the norm in new builds. I have even seen windowless bathrooms in some award-winning house designs. How depressing is that? I believe that hallways too, whether in flats or houses, should also be illuminated by some natural light either directly or indirectly.

I’ll re-iterate what I’ve said before in a previous post: every room in a house should have it’s own window. Who would want anything less?

2 comments

Single Aspect

01 January 2011 15:17 GMT

Here’s another one for you. It makes you wonder if the Government has introduced a window tax we’re unaware of www.rightmove.co.uk/property...

Should that ever disappear (when the house is eventually sold) see it here:- http://www.singleaspect.org.uk/?p=4878

A. Hussein blog author

01 January 2011 15:41 GMT

Thanks for the link. That really is a shocking example!

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