You've finally made it to the long-awaited beach. The sand sparkles, the sea stretches to an azure horizon and the cloudless sky envelopes you. Nothing stands between you and holiday nirvana - except for the inescapable fact that it's too darn hot for comfort.
We've all been in this situation and we all know how to deal with it. Human beings are remarkably adept at climatic adaptation - yet we don't always follow through our bodily wisdom with similar good sense when dealing with our houses. So, before you phone the company that supplies energy-intensive air conditioning , here are a few tips on keeping cool at home, using environmentally benign beach behaviour as the starting point.
The first thing you do is put up a parasol and get in the shade. In traditionally rainy Britain few houses have decent solar shading, yet keeping the sun's energy out of the building is the first line of defence against overheating. Closing internal curtains and blinds will help by reflecting the light back out of a window, but lots of heat still gets trapped inside. If you have rooms that overheat quickly, follow Mediterranean design and install external shutters or louvres to keep the direct sun out altogether. Fixed horizontal louvres shade the high summer sun but let in plenty of indirect light. Shading from trees, climbers and other vegetation will also do the trick, and deciduous plants will generously jettison their leaves just when you want the sun's warmth back.
Next you fan yourself with the latest copy of Hola! Air movement can cool a house down very quickly if you are able to channel it effectively. Don't just open a window, open internal doors too in order to encourage ventilation across your house, and up it. If there is any wind at all outside, experiment to see which combination of open windows and doors will catch it most effectively. You may be surprised at the breezes you can create without resorting to electric fans. Good night-time ventilation is important if your house is made from heavy materials, as these absorb the heat during the day, keeping the temperature down, then release it overnight.
Then you lie back and do absolutely nothing except stare at the sky, thereby minimising your own heat output. Internal heat sources are more of a problem in offices than in homes because of all the equipment humming away in the background, but opting for the most energy-efficient lights and appliances will still make a significant difference to the air temperature in your home. A 150W tungsten bulb lighting your living room will produce more heat than you when you're sat on the sofa.
You're more comfortable, but you still quietly perspire. The evaporation of water is an effective cooling mechanism because so much energy is absorbed when water turns into vapour. If you don't have space for a water feature in your front room, use plants instead, as their continuous transpiration of water has the same effect. A lush, shady garden is the perfect place to cool off.
Feeling thirsty, you reach for your well-insulated cool box. You need insulation in your home primarily to stay warm in winter but it will also help keep the heat out in summer. This is especially important for rooms at the top of your house, where a poorly insulated roof will turn the ceiling into one big radiator. White exterior walls will also help to reduce heat transfer through the building fabric by reflecting the light - all those bright-white Greek houses are designed to be cool as well as charming.
Finally, stay on the beach for a week, and you will not notice the heat at all. Our perception of a comfortable temperature is very relative and highly adaptable. Resist the temptation to moan when the temperature hits 30C and you might find yourself enjoying the experience, especially if you put all the money you've saved on air conditioning towards a supply of frozen margaritas and blueberry flavoured ice cream.
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The Peace Lily, Spathiphllyum gigant, is not only mighty quick at transpiration, it also absorbs lots of nasty chemicals. £9.95 from www.crocus.co.uk.
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The world is full of beautiful buildings that are cooled passively. The Alhambra (at www.greatbuildings.com) shows how many of the strategies described here were used by the Moors in the 14th century.Reuse content