Perhaps I may make some progress. We all recognise the need to build more homes, and they should be sustainable, but we do not need to make building them more difficult than necessary. We need to consider whether it is realistic for the majority of builders to deliver even higher standards without unduly affecting site viability or housing delivery.
In the productivity plan, Fixing the Foundations: Creating a More Prosperous Nation, published last summer, we committed to keeping the energy standards under review, and we will ensure that any changes that may be introduced are cost effective. This includes looking at not just new buildings but across the whole of the existing building stock, where carbon emissions tend to be higher and energy efficiency is poorer than for new homes.
In raising or lowering the energy requirements for new homes, it is always necessary to consult carefully with industry. We should not forget that we are talking about a technical area which impacts across the construction sector. It would therefore not be workable to deliver the proposed standard within six months. Even if it were, it is not prudent to have such a rigid framework for delivery in the Bill, or to set requirements such as this in primary legislation. If, in the light of consultation, any slight adjustments to requirements were needed, we would not be able to make them without further primary legislation.
I understand the intention of the new clause proposed by the noble Baroness, Lady Parminter, but it would create a significant regulatory burden on housebuilders at a time when we need to increase housing supply and access to home ownership. We are giving the industry breathing space to ensure that it catches up with the already highly energy-efficient new standards that came into force only in 2014.
I would like to say more in attempting to address many of the questions that were raised, particularly by the noble Lord, Lord Krebs. Some builders, big and small, already go beyond the current minimum standards. New homes built to the performance requirements introduced by building regulations in 2014 are highly energy efficient. They need to have high levels of insulation, double-glazed windows with low-energy glass, and A-rated, high-efficiency condensing boilers.
Perhaps the nub of this debate is the difference the amendment would make to new homes. I understand the strength of feeling on the Liberal Democrat Benches
in particular, but the current regulations have already pushed the fabric energy performance of homes to the point where further increases may result in only marginal returns in energy efficiency. Therefore, to meet the proposed levels of carbon compliance, homebuilders would need to consider further technical solutions for providing heat and power to the home—for example, photovoltaic panels, solar hot-water systems, and air and ground-source heat pumps. These would add considerably to construction costs for homebuilders. The noble Lord, Lord Stunell—