Badly built offices are costing British business millions of pounds each year in wasted energy costs, according to research released today by international architects, Gensler.

The report, 'Faulty Towers: Is the British Office Sustainable', reveals that close to a third (27%) of companies' property-related energy consumption could be saved by making offices sustainable - the equivalent of 1.8bn kg in carbon emissions.

Nearly three quarters (72%) of companies' property directors believe that business is picking up the bill for badly designed, inefficient buildings and more than a quarter (26%) state that bad office stock is actually damaging UK productivity. However, the majority of property developers (67%) will only go as far as legislation demands when it comes to energy efficiency.

Government plans to grade buildings with an energy performance certificate (in response to the EU's Energy Performance of Buildings Directive) will therefore be instrumental in improving Britain's ailing office stock. Chris Johnson, Managing Principal, Gensler said: "The commercial offices which currently dominate our city skylines are costing business and the environment dear. With around 40% of energy consumption in the EU coming from the building sector, more sustainable and efficient design offers an enormous opportunity for reducing energy wastage, reducing carbon emissions and cutting costs." According to the study, spiralling energy costs have pushed energy efficiency up the business agenda, with business aiming to reduce property energy consumption by 12% over the next 5 years. On average, business is willing to pay 10% more in rent for efficiently designed and constructed buildings.

The study reveals that businesses have the smallest influence on the design and build of their workplace - just 11% impact. More than half believe that developers do not build with the end-user in mind. And despite the recent proliferation of flagship towers, 87% of businesses would prefer an efficient office to an iconic building.

Sir Digby Jones, former-Director-General, CBI, said: "Sustainability has increasingly become part of the language of commercial property. Yet despite individual examples of good practice, energy use in the commercial sector has risen rapidly and too often the development industry perceives a lack of demand for energy efficient buildings. This needs to change. For the market to develop it is vital that investors, developers, business users and the government work together to make a compelling business case for sustainable buildings. Only then will they be built. As the Gensler report shows, such foresight could save UK businesses millions of pounds every year in reduced energy costs". Whilst business welcomes the grading of buildings to raise the standard of the British workplace, developers have a stark warning about the impact of such measures on commercial property investors. 75% of developers believe that poor energy efficiency will have a negative impact on the value and transferability of current commercial property assets when certification is imposed.

Chris Johnson, Managing Principal, Gensler said: "Property fund managers are effectively sitting on an investment timebomb. The introduction of building certificates will shorten the lifespan of commercial buildings constructed before the new regulations, and we expect the capital value of inefficient buildings to fall as a result.

"We expect to see a shake up in the market, with investors disposing of inefficient stock, upgrading those buildings which can be adapted and demanding much higher energy efficiency from new buildings."