low energy and solar solutions
Our Part L (Building regulations: Conservation of Fuel and Power) focus is primarily on new non-domestic buildings. Part L is divided into Part L1 which relates to domesic and Part L2 which is for non-domestic buildings. These are further divided up into A and B where A is for new buildings and B for existing buildings. Extensions to non domestic buildings may be assessed under Part L2A or Part L2B depending on floor area and its relationship to the area of the existing building. The accompanying notes refer only to Part L2A.Part L2A is assessed on five criterion. The headings link to more detailed information on our services in these areas.
This involves the calculation of a predicted carbon dioxide emission rate from the building and compares this with a building with identical geometry and functions but with nominal specifications similar to minimum standards. A naturally ventilated building will need to emit 23% less, an air conditioned/mechanically ventilated building 28% less than a building built to nominal specifications. A building incorporating some mechanical ventilation will have a target improvement in between these values depending on the proportion of mechanically ventilated zones. Emissions represent only those from providing the main building services (heating: space and water, cooling, ventilation and lighting).
- external fabric: individual and area weighted U values.
- Heating (and cooling if appropriate) plant efficiencies and controls
- Pipework and ductwork insulation
- lighting efficiencies
- light switching
- detailed glazing specification, shading provided by the building, adjacent buildings and fixed shading devices
- fixed values (CIBSE TM37) for occupancy and lighting based on space function
- weather data for the region (CIBSE Guide A)