Improving energy efficiency in buildings

Pick the low hanging fruit first

Knowledge of the energy factors taken into consideration in the EPC (SBEM) calculation is useful. Energy efficiency measures termed low Hanging fruit may be carried out in anticipation of the survey. In general the factors that the EPC calculation takes into account are outlined below. Payback should be considered.

Building envelope: Insulation

Loft Insulation to reduce heat lossDuring the EPC survey, the building is inspected to determine the thermal performance of the building envelope, the U-value of the walls, roof, floors etc. Built to building standards, the newer the building, the better the building will be insulated. Older buildings can be retro-insulated and loft insulation is a good example.

Building envelope: Glazing

High Tech Double Glazing
The double glazing used in a building is taken into consideration. A building with modern, double glazed units in a building would give a better EPC result than single glazed wood framed. Argon filled units with a low-e coating give better performance.

Building services: HVAC types & controls

Heating types & controls in commercial buildingsThe heating system within a building is usually critically important when an EPC calculation is carried out. By choosing to heat / cool the building in the most CO2 efficient way will ensure the EPC rating is maximized.

Fuel type, whether it is electricity, gas, oil etc is an important factor in the EPC calculation. Different fuels have higher emissions factors than others and heating fuel type is a determining factor in whether a building has a good EPC rating.  As an example, electricity has a higher emissions rate than gas so a building with a gas heating system would be expected to get a better EPC rating than one with say direct electric resistance heating.

Heating / Cooling controls such as Weather Compensation and Time and Temperature Controls will reduce unnecessary energy use and improve the EPC rating.

Building services: Lighting types & controls

Energy efficient lightingLighting can have a big effect on the EPC rating. Low Energy lighting throughout the building reduces energy use and will lead to a better rating. Switching off lights reduces energy use. Installing lighting controls such as Infrared Occupancy Sensors in ancillary areas or day-lighting controls in large, highly glazed areas will improve he EPC rating. Lighting types and controls is particularly important to retail type buildings.

Renewables: PV, solar thermal and wind

Renewable Energy in commercial buildings
When the basics are right then using on-site renewable’s such as Photovoltaic, Solar Thermal, wind turbines, micro hydro may be considered to fine tune a buildings result – possibly improving a building from a B rating to an A rating! Many of these are more practical than others.