To lose weight one must eat less and exercise more. It’s the same with becoming more sustainable – we must use less and recycle more. So we have to wean ourselves on to a healthier diet, maybe switching from chocolate bars to digestive biscuits on the way to a seasonal fruit salad

But when we try to deliver environmentally healthy projects, what worries me is the spin, greenwash and fad diets at every corner. There’s a classic example of greenwash on every garage forecourt: petrol pumps stand proudly in their green livery selling ‘energy’, as if associating the colour and the word is a step in the right direction.

Having recently moved into our new ‘passive’ house, I attended this year’s Ecobuild event with a heightened awareness of the need for healthy eating. Walking round in search of healthy ingredients, it was great to see the advancement in alternative building methods: there were timber-framed houses, renewable technologies and ‘energy saving’ products galore.

But I was still alarmed at the number of exhibitors that had slipped through the eco filter. One thing that makes me laugh is when you have companies selling new types of concrete shuttering. Yes, it’s no doubt innovative and quicker – but what is it doing at Ecobuild? You’re still using concrete, when most buildings aren’t designed to justify its embodied energy. Then there’s the ‘sustainable technologies’ that are sold citing unrealistic performance data – ground source heat pumps are a particular culprit.

Somehow, I got the feeling that many companies were simply supplying chocolate bars in green organic wrappers.

Taking a break, and quietly eating an apple (and a chocolate biscuit, I must confess) I listened to Paul King, chief executive of the UK Green Building Council, as he presented his organisation’s proposal for a Code for Sustainable Buildings. This new loose-fit framework would accommodate existing methods of measuring eco-credentials, such as BREEAM, and would cover all non-domestic buildings. It would require all buildings, new and old, to undergo a regular health check, with public disclosure of calorie intake. Naming and shaming – that sounds good.

The proposed code is more digestive biscuit than fruit salad in its conviction

The proposal undoubtedly leads us in the right direction, but I can't help but think it’s more digestive biscuit than fruit salad in its conviction. The balanced diet seems too difficult to digest. As I see it, any sustainable buildings code needs to focus on changing the habits of the user, and there’s a danger that a top-down code will only address property and design professionals without engaging the occupiers. If we don’t look at unsustainable human behaviour, we will do little to improve overall sustainability, no matter how restrictive we make the buildings.

If we are to have a new Code for Sustainable Buildings, I hope that it will iron out some of the bizarre inequalities we faced in assessing our eco-house against the Code for Sustainable Homes. Receiving no credit for using small local crafts and materials due to lack of ISO or FSC accreditation was daft. Likewise, there was no recognition for treating all our waste water on site, and the fact that we got no credit for a vegetable garden and compost system unless I formed a nice flat path to from the back door for easy wheelchair access (out of concrete, perhaps?) just about topped it off. If supporting sustainable produce isn't encouraged by the code, what on Earth, or beyond, is?

Codes should act as guides to elicit change. This is what the Building Regulations do (albeit by reducing the fat content of a Mars bar rather than promoting apples). But the astoundingly complex measurements and calculations required by the Code for Sustainable Homes leaves me thinking something has got lost in translation. Recent changes now mean that a house with a swimming pool can still be assessed as code 4 or 5. Not very green, you’re thinking? That'll be the chlorine!

The problem with the Code for Sustainable Homes is that it’s highly prescriptive. We need a code that’s more like the Building Regulations – as long as you design in the spirit of the regulations, there’s room to skin the cat in more than one way.

So I hope that a Code for Sustainable Buildings will be bold in its leadership and wise in its judgement. It must lead us effectively, not eradicate the small and beautiful. We all know that fresh and local is not so much a fringe activity, but an essential ingredient in cooking a healthy meal.