Energy Performance Certificate Guide

Energy efficient home
Loft insulation
Underfloor heating
Thermostatic radiator valves
Cavity wall insulation

Knowing the difference between the running costs of a B and E rated property could potentially save you tens of thousands of pounds.

A property’s EPC provides you with information on the energy efficiency and likely running costs for heating, lighting and hot water for that property.

If you are trying to decide on which property to buy - especially whether to buy a new build or an older property - comparing their EPC ratings and knowing the potential running costs is valuable information.

Just take a look at the table below. Multiply these over, say, 10 years and you can see the massive differences in costs.

Older properties can be improved, however, the scale of the improvement is limited due to the construction of the property eg. it is not possible to fit underfloor insulation to concrete floors.

Energy Efficiency and costs
Energy Efficiency Rating chart

Understanding your EPC

New Designs

New homes are achieving high standards, this is due to improvements in insulation, high specification materials such as Low Energy windows and an improvement in the quality of build. These factors contribute to an improved building envelope in terms of the fabric that is more air tight and reduces the loss of heat and energy through the building and subsequently makes the building more efficient.

Energy Performance Guide

The A-G scale

The A-G scale is a format that many consumers will be familiar with as this is shown on many household white goods and is instantly recognizable. The EPC shows this format to allow proposed purchasers the ability to make an informed decision by providing a scale that is calculated on a standard occupancy of the home. Occupants inevitably use a home in terms of heating, lighting and hot water in vastly different ways and this would impact on the results greatly. The standard occupancy then allows the varying factors to be taken out of the equation and provides direct comparisons to be made between vastly different homes. The scale is shown with 'A' being the most efficient home and 'G' being the least efficient, there is an accompanying value to each energy band which shows the exact value (1-100) which also allows the purchaser to see where that home sits in its relevant band, i.e. nearly in the next band up.

Additional information on the EPC

There are further elements to an EPC that a purchaser should be aware of. Another feature on the EPC is the Potential rating of the home and this is detailed by showing the possible improvements which could be made, with the associated cost, and the potential saving this would provide. Many older homes will have more scope for improvements in the Potential rating but will have a large associated cost and therefore the benefits financially won't be gained for a substantial period of time.

One of the biggest contributors to climate change is carbon dioxide (CO2), with the energy used from heating, lighting & power from our homes being responsible for over a quarter of the UK’s CO2 emissions. The EPC shows the proposed purchasers an idea of the CO2 emissions produced by that property against the average household.

The EPC also provides a breakdown of the property’s energy performance, this includes a simple rating from very poor to very good for each feature of the dwelling, such as windows & heating controls.

Running Costs

Purchasers should look in detail at the running costs and the potential running costs as these should take into consideration any payback period i.e. the time it takes to pay for any additional features that have been incorporated to improve the efficiency of the home.

Heat will always flow from a warm area to a cold one. So keeping the warmth in is critical to the cost of your energy bills. These are just some of the key features that we build into our homes.

Deep insulation to lofts.

Brick and thermal block walls with wide cavities filled with insulation.

Houses have highly insulated floors with energy efficient underfloor heating to the ground floor and thermostatically controlled radiators to other floors. Room temperatures can be controlled individually to reduce wasted energy.

EPC background

The continued improvements in energy efficiency over the last 20 years have been driven by the government through the process of building regulations. A SAP calculation forms the basis of an EPC by calculating the energy required to heat, light and provide hot water for a theoretical house with a structure that is in line with the relevant Building Regulations, this is then compared to the proposed dwelling, any improvement measures, above and beyond the Building Regulations at the time of construction, contribute to the home having a higher energy band, therefore being more efficient and cheaper to run.