FT Article written on Eco-renovating London flat (Apr12)

In 1986, when I bought my London flat, I re-painted and re-carpeted it throughout. Since then it’s had a few minor makeovers, some carried out by tenants, as the property has been rented since 1995. But in 2010 I decided to do a major overhaul – and the key objective was to make the flat as green as possible.

I’ve worked as an environmental consultant for 25 years and have written nine books on eco- issues, including green building. Yet despite all of my experience, I missed “Superhomes” status on this project by just 1 per cent. Superhomes is a scheme that promotes eco-renovation. To obtain their accreditation, the carbon emissions of a property have to be reduced by 60 per cent or more – my rating was 59 per cent.

The pivotal factor in falling short appears to have been my windows. The Victorian sash windows had been in a terrible condition, rattling in places and with large gaps that let the air in and the heat out. I got them repaired and draft-proofed, which did reduce the heat loss, but clearly I should have had them double-glazed.

My mistake was to repair the windows before eco-renovating the entire property. I subsequently discovered that I could have used Slimlite double-glazing in the existing windows. One compensating factor is that I’ve installed insulating blinds throughout the property (although they can only retain heat when they are pulled down).

Insulation is the key to eco-renovation. Given that my flat is at the top of the building, I wondered if I could exclude insulating the floors and instead benefit from the heating in the flats below. “Definitely not,” said my architect, Jerry Tate. There were two reasons why. First, insulation provides acoustic benefits, reducing noise transfer between flats. Second, the flat below could be vacant and would therefore not send warmth through to my floor. Taking account of both performance and eco-credentials, I chose a range of insulation products from Knauf, including glass fibre wall insulation, 85 per cent of which is composed from recycled glass bottles.

I had installed an efficient gas condensing boiler about a year before my eco-renovation started. This was important for improving my energy efficiency, but what many people don’t realise is that thermostats can also make a big difference. Honeywell, who installed my controls, explained that room thermostats are essential. These will send a message straight to the boiler about when heat is needed. The real key is for thermostats to be easy to use, which means people are more inclined to turn the heating off when it’s not needed.

As well as innovative controls, I’ve installed a touch screen information system called Hab Shimmy, which will relay information about electricity, gas and water use, as well as information about local events and transport systems. For example, you can find out bus times and when the next recycling collection is due. Kevin McCloud, of Grand Designs fame, has used the acronym “Hab” (happiness, architecture and beauty) in his company name – Haboakus – and launched a range of associated products.  <2020 update – This product was discontinued)

Another energy-saving system I installed was a master switch, which is positioned near the front door and turns off a group of lights and sockets. Clearly there are sockets that have to stay connected, such as those for the fridge, cooker and washing machines. These, and a couple extra that could be used for re-charging phones are matt, rather than shiny, so you can tell the difference – and they’re not connected to the master switch.

Even the paint has an energy-saving dimension. I used a Dulux Light and Space colour, which makes the room brighter and means that you’re likely to turn the lights on 20 minutes later in the day. And, of course, the lights are LED, which give about three times the performance of halogen lights for the same power – they should also give optimum performance for over 10 years.

I have also installed water-saving features in the flat with low flush lavatories and low flow taps. The Ecocamel shower head is another water-saving innovation: it aerates the water giving the impression that you’re using more than you are – tests by Which? indicated that this could reduce water use by a third and pay for itself within a year.

The main tiles in the bathrooms are from Domus and have a 40 per cent recycled content (made from tile factory waste) and I used their more expensive mosaic tiles (made almost entirely from recycled windscreen glass) for contrast. The kitchen worktop is made from recycled green glass bottles and is the most striking eco-feature in the property.

Choosing the flooring was one of the most challenging tasks. In the sitting room and kitchen area I wanted something that was durable, sustainable and looked good. I opted for bamboo, one of the fastest growing plants on earth. I chose one that wouldn’t get dented by high heels and so will last a long time. It looks good, too: the bamboo has been squashed flat, so the natural ridges are visible.

I chose cork for the bathroom floors because I wanted to play a part in preserving the ancient cork forests, which are under threat as demand for wine corks decreases with the growing popularity of screw top bottles. A cork tree can live for 200 years and the cork can be harvested without cutting the tree down.

The rest of the flat was carpeted. I managed to get what I used from an over-order from Interface carpets, one of the leading sustainability companies in the world. Interface told me that companies often order more than they need, and so I could use leftover stock.