Implementing EU directives alone is an insufficient response to the emerging issue of energy efficiency and the government here should introduce a voluntary classification system for industrial property similar to those operating in the UK and the United States, the report published by CB Richard Ellis (CBRE) claims.

According to the report, titled 'Sustainability and Energy Efficiency' the voluntary assessment system in operation in Britain since 1990 is an effective benchmark for measuring the environmental performance of buildings.

Commercial properties are rated on a scale of pass, good, very good or excellent, following assessment under the headings: building management, health and wellbeing, energy, wransport, water, material and waste, land use/ecology, and pollution.

In Ireland the 'green agenda' will ultimately have to be helped along by policy intervention and the setting of minimum standards by government.

The report points out that some local authorities including Fingal, Dun Laoghaire/Rathdown, Wicklow and Wexford county councils have taken the lead in this regard by implementing their own mandatory planning requirements in an effort to promote sustainability.

Very soon the value of buildings will start to reflect their environmental credentials, the report claims. A building's energy rating has the potential to become a very significant negotiating tool at purchase, letting, sale, or at rent review stage and values and yields will be impacted.

If high performance energyefficient buildings are perceived as less risky, this perception could manifest itself in a variety of ways such as improved marketability, improved lettability, better tenant retention and less voids, all of which would enhance value.

All of these issues will be more topical and relevant if a UK type voluntary grading system is adopted here.

"Even though the issues are being widely discussed, as long as there is no regulatory requirement to produce sustainable buildings, and occupiers are not asking for them, developers won't provide them, " the report states.

"While the techniques for developing green or sustainable buildings have existed for years, a compelling case demonstrating the economic rewards has not been made.

Developers really now have no choice but to embrace sustainability to 'future proof ' buildings they are developing to ensure that the property gets planning approval, attains appropriate funding, appeals to all potential occupiers and maximises the property's rental potential and boosts its investment value.

"Developers have no choice but to adopt a pro-active approach to deliver sustainable buildings that deliver 'added value' when developing new buildings and refurbishing older buildings.

"While they may not initially achieve a rental premium from occupiers for providing a green building, the long term investment value of the asset will undoubtedly be enhanced and the future value of the building will be protected."

The report claims that as well as an economic responsibility to provide quality buildings that meet occupier needs, developers have a social responsibility to meet the green agenda.

Although it may cost more initially to incorporate green features into buildings ultimately this cost should be reduced as new technologies emerge and developers gain experience in constructing environmentally friendly properties.

"Properties which do not embrace sustainability are less likely to attractive to tenants, " the report says. "There is no doubt but that this will have implications for value and that sustainable buildings are in the future likely to achieve superior rental and capital values as well as lower tenant turnover and shorter void periods. Developers essentially need to develop buildings that their occupiers want to locate in and if occupiers demand energy efficiency design, landlords will have no choice but to provide this."