Diary Of An Eco-Builder

Make use of renewable energy by letting the daylight in – it's a vital natural resource

The renewable energy I have in mind is daylight, an extraordinarily important natural resource that profoundly shapes the design of our homes. It may not yet be customary to design houses that store solar energy for warmth or that convert solar energy into hot water or electricity, but no architect would dream of spurning natural light.

Daylight has qualities that can never be matched by artificial light. We value its vibrancy, its daily ebb and flow, its intimate relationship with the seasons, and its unpredictability. When daylight is plentiful, we are delighted; when it is in short supply, we get Seasonal Affective Disorder. Yet despite being showered with these riches, we still don't make the most of daylight in modern house design, not least because easy-on electric lights have lowered the priority of daylighting among the many competing concerns of architects.

Currently, Tree House has exceptional daylighting as our unsheathed timber frame provides a line of sight right through the building. When the walls get their plywood skin next week we will have a first indication of the effectiveness of our ultra-efficient Swedish windows in lighting the interior (www.swedishtimberproducts.co.uk).

But there is more to daylighting than decent windows. On the ground floor of Tree House our large open-plan living space enjoys extensive glazing, but this all faces one way – west. Hopefully, this daylight will still get deep into the house thanks to the shortage of interior walls, the use of light colours for reflective surfaces and the sparkling addition of the pond that runs the width of the house just beyond the windows. When necessary, our external venetian blinds will minimise glare without throwing the room into darkness.

Even with these measures, we were worried that the kitchen space at the back of the room might be too dark to make morning coffee without turning the lights on. The solution has been to puncture the wall between the kitchen and the small laundry/shower room beyond and so bring daylight into the room via the east-facing laundry window.

We are plugging the hole in the wall with something rather special: a 5ft panel of contemporary stained glass, designed to express the beauty of sunlight seen through the canopy of a tree on a summer's day. Made by Sarah McNicol of Juicy Glass (www.juicyglass.com), this stunning panel has inevitably morphed from a little eco-idea into the design centrepiece of our kitchen. If you have dark spaces in your home in the middle of the day, avoid turning the lights on by keeping surfaces light and bright, choosing window coverings that can be adjusted to balance useful light with glare control and positioning key task areas near to windows.

The most important time to consider daylighting is when you are investing in major changes to your interior space. Then you can improve your windows, add roof lights (Velux produce high quality, energy efficient options, www.velux.co.uk) or even install sunpipes that bring daylight deep into your house from your roof (www.sunpipe.co.uk).

This is also the time to fully rethink your household activities to better suit the sunlight (see the paintings of Vermeer for inspiration).

And while you're about it, remember that daylight is as playful as it is eco-friendly. You may not want to live in Chartres Cathedral, but stained glass, water and characterful shading can all help to play their part in making your living space simply divine.