But so-called “tax on conservatories” doesn’t apply to the majority of conservatories

The Federation of Master Builders has issued a fresh warning to the government that its plans to make it compulsory for homeowners extending their homes to make energy efficiency improvements won’t work.

The warning comes amid a growing media storm over the plans, which were first published in January, but have not hit the headlines until this week.

The changes to Part L of the building regulations would mean homeowners making home improvements would likely have to spend an additional 10% on measures, such as insulation, to improve the energy efficiency of the rest of their house.

The FMB today re-issued survey results from last month, which revealed that 70% of builders felt the changes were not feasible and would push consumers towards cowboy operators.

This week, the Daily Mail, the Telegraph and the Times all branded the changes a “tax on conservatories”.

But as sustainability expert David Strong, noted in his column for Building in February, conservatories are conspicuous in their absence from the revised regulations.

Currently Part L only applies to conservatories over 30 sqm, which excludes the majority of conservatories. The revised regulations do not change this provision.

Conservative MP Tim Yeo, chair of the energy and climate change committee, said that the changes were wrong: “You’ve got to find ways of making the public more enthusiastic and I think compelling people who have applied for planning consent to make some alteration to their home isn’t necessarily going to help,” he told the BBC Radio 4 Today programme.

The government defended the plans against criticism, saying it the changes will drive take-up of its Green Deal and won’t cost householders anything up-front. It has said the move will also drive much needed increases in the energy efficiency of the building stock.

But as Building reported in February there has been little research by the Department for Communities and Local Government into whether the requirement actually works in commercial buildings, where such a requirement has existed for years.

Plus, a number of holes in the plans were identified by the construction industry at the outset of the consultation, including the ease with which householders can avoid meeting the requirements if they choose.