Let’s build on good relationships to make energy efficient home improvements
Chancellor Rishi Sunak’s decision to cut the VAT rate on solar panels and heat pumps to 0% for five years in his spring Budget shows how far energy efficiency is moving up the national agenda.
The tax giveaway will doubtless open the floodgates, encouraging more people to invest in green products amid the relentless rise in energy prices, while this summer’s upcoming reboot of Building Regulations will prompt another big change in behaviour. These outline how new homes, as well as extensions and retrofits, need to meet higher standards and produce around 30% less carbon emissions, while offices and shops must produce 27% less.
This next iteration of Building Regulations is significant and introduces a stronger correlation between heat loss, ventilation and overheating. More insulation and air tightness will be required by Part L, so contractors need to understand the air pathways that can exist in the building fabric. Common issues include not properly sealing behind the plasterboard finish and behind skirting boards, poorly fitted windows and doors or not sealing the conduits for pipework and cables passing through the walls or floors. A considerable amount of heat is lost through these cracks and holes in both new-builds and existing dwellings which can result in draughts and impact comfort.
Housebuilders will have to provide detailed Home User Guides and a library of photographic evidence throughout the construction of every new home, while there’s also a new efficiency metric for the whole house calculation method for new extensions.
However, when you put more insulation in a building, there’s a risk of over-heating, which is where the new Part O comes in. This sets maximum limits on the amount of glazing and means every home will need to be assessed using either a simplified method of checking window sizes and openable areas, or an advanced 3D thermal model for those that are at a higher risk of overheating, such as central London apartment blocks.
Proper ventilation goes hand in hand with air tightness, and Part F of the regulations set out new standards for a building’s eco-system, ensuring builders install better ventilation systems to keep fresh air flowing and prevent the spread of airborne viruses in new non-residential buildings. More people are now opting to install a mechanical ventilation with a heat recovery (MVHR) unit. This allows for a controlled environment, introducing fresh air and extracting the stale air, but recovering the heat so that it reduces the amount the central heating system needs to provide. It can produce cost-savings on gas or electricity while improving a home’s air quality.
However, MVHR does need to be designed, installed and commissioned properly to gain the benefits; the complaints we’ve heard from homeowners about MVHR were primarily due to poor installation.
The rules apply to all projects from 15th June, except where a building notice has been given or full plans have been submitted with local councils, and will cover all projects from 15th June 2023. This paves the way for the Future Homes and Buildings Standard in 2025 when yet another update will require 75-80% less carbon emissions – and will eventually mean all future homes won’t need retrofitting.
However, some in our sector don’t feel that the new regulations go far enough – and it’s fair to say the government could have done more – although more ambitious targets might have created undue pressure on the industry; imagine if the government had insisted that every new home needed a heat pump instead of a gas boiler. There is already pressure on the national grid and extended lead times on some products such as heat pumps. But an eco-system of solar PV to generate electricity to power the heat pump along with MVHR and a battery storage solution could actually reduce a home’s reliance on the national grid and lower energy bills.
While there has always been an assumption that rudimentary calculations had been done to consider over-heating and ventilation in new builds, these new rules task energy assessors to prove it. They will certainly add to the build cost – both for the materials and assessment process – but the result will be a healthier building that costs less to run and does less harm to the environment. Ultimately, if there’s less heat loss, there’s less demand for heat and that means we’re burning less fuel, and moving towards a low energy environment and that elusive net zero. The house may also be worth more – see our blog ‘Green Homes Premium worth up to £40,000’.
It’s all about finding the sweet spot: the optimum specification for a building that complies with regulations, satisfies the budget and delivers a building that’s equally good in terms of energy efficiency and cost savings. To do this, it makes sense that energy assessors, architects, building control and builders all work together – and early on in the process – to ensure what has been designed hits the mark before it goes to tender, so avoiding costly or irreversible mistakes. While that might not go down well with some builders, we believe collaboration really is the way forward – and we’re ready for the challenge.