ABOUT PART F

Text from building control NI

Amendments to the Building Regulations were introduced with effect from 30th November 2006. These amendments relate to energy conservation, flues and fuel storage, access to commercial buildings and consequential changes regarding glazing and stairs and follow consultation by the Department of Finance and Personnel, which has responsibility for making and amending the Building Regulations.

PART F - CONSERVATION OF FUEL AND POWER

In 1997 the Government gave a commitment at the Koyoto Conference to reduce the carbon emissions from the UK as the result of burning fossil fuels by 20% by 2010. The European Parliament passed legislation requiring Member States to put in place legislation, under the Energy Performance of Building Directive (EPBD), to ensure that all energy usage in new and existing buildings is assessed and made known to owners or those renting, leasing or otherwise using the building.
As buildings are currently responsible for about 50% of the total UK energy use and dwellings account for approximately two thirds of this so it is felt that amendments to the Building Regulations will go a long way to reduce the energy consumption of buildings. The amendments to Part F result in a reduction in carbon emissions of some 40 - 45% on 2005 levels with a similar reduction in fuel bills. The National Methodology established for calculating energy rating for dwellings is SAP 2005 and SBEM for buildings other than dwellings. These are complex computer software programmes which must be used when calculating the energy rating.

The changes aimed at cutting carbon dioxide emissions and consider the following elements of the building:-

• Building type, shape & size
• Insulation levels of floors, walls, roofs and windows (U-values)
• Number, size and type of windows and orientation of the building
• Boiler efficiency, fuel type and controls of space heating and hot water
• Secondary heating efficiency and type of fuel used
• Construction - quality of the construction and airtightness
• Efficiency and controls of fixed internal and external lighting
• Any low or zero carbon technologies, such as solar panels, wind turbines or photo voltaic cells.

For designers the changes in Part F will be far reaching, requiring the new building to produce less carbon dioxide than a standard notional building. For a dwelling the procedure will be as follows:

1. Establish the Target Carbon Dioxide Emissions Rate (TER) {measured in kg/m2/yr} using the characteristics of the proposed building and the SAP 2005 software package.
   
   
2. Undertake detailed design of the dwelling -use the exact figures relating to the criteria mentioned above (U.values for walls, floor, roof, windows, boiler type etc.) to produce a Dwelling Carbon Dioxide Emissions Rate (DER) again using the SAP 2005 computer software.
   If the DER is less than the TER the dwelling will comply with the Building Regulations.
   If the DER is more than the TER then the design needs to be revisited and measures need to be taken to reduce the DER - this may involve use of a more efficient boiler and heating controls; or increased insulation in walls, floors or roof; or windows with a lower U value; or low or zero energy technologies -such as a solar panel to heat the water; or a combination of all these elements.
   Thus it can be seen that a holistic approach looking at all of the elements of the building is necessary to ensure the dwelling complies with the Regulations.
   There are also limiting values set for elements such as the fabric of the building to prevent condensation and ensure a reasonable level of passive insulation. This ensures that in the event of any future removal of energy saving equipment the building remains reasonably energy efficient.
   
   
3. The orientation of the building must be considered to prevent solar overheating.
   
   
4. Builders will need to "quality assure" the work of their tradesmen by ensuring specified construction details are adhered to and are regularly checked. There will be a requirement for air testing of a dwelling to ensure that heated air is not escaping through "holes" in the building. Heating and ventilation equipment and controls will have to be properly commissioned with Certification by suitably qualified persons.
   
   
5. Adequate operating and maintenance instructions, in the form of a Manual, set out in language which the layman will understand, must be provided for the users of the systems. At the end of every job the energy rating of the "as-constructed" building must be calculated, and a copy of the Energy Rating must be displayed in the building.

For the 12,000 new houses built annually in Northern Ireland there are approximately 660,000 existing dwellings. The amended Regulations will require measures to be undertaken to improve the energy rating of existing properties when thermal elements such as roofs, walls or floors are significantly altered or controlled fittings and services such as doors, boilers, hot water heaters, ventilation and lighting systems are replaced. A new Energy Rating calculation will be required when work affecting the energy efficiency has been undertaken.
Similarly with non-domestic buildings the design of the building must incorporate energy efficient construction methods with additional energy saving measures to reduce carbon dioxide emissions to approximately 40-48% below 2005 levels.

Energy Rating calculations will be required for new non-domestic buildings when constructed and when alterations or extensions or addition or replacement of Controlled fittings or services are undertaken which will effect the energy efficiency. The energy efficiency calculation for buildings which are not dwellings uses the SBEM methodology. The basis for the calculation is the establishment of a carbon dioxide emission for a notional building of similar form to that proposed; this notional figure is then adjusted by an "improvement factor"l related to the type of services in the building and by a factor of a further 10% known as the LZC factor (Low or Zero Carbon) to encourage the use of these new technologies in commercial settings. Similar requirements will apply to a non-domestic building as to a dwelling requiring quality assurance of construction, air testing, commissioning of mechanical and electrical equipment and operation and maintenance instructions. Where work is being undertaken to an existing commercial building over 1000m2, such as the creation of an extension the existing building must be brought up to the latest thermal standards, subject to a 15 year payback period.

As with domestic construction when alteration or renovation is being undertaken to a non-domestic building there will be requirements to bring particular elements of the construction up to the thermal standards which are currently acceptable. When the construction work has been completed an energy rating calculation will be required by Building Control and the details of the energy rating will have to be included in the building logbook and displayed in the building.

For full technical booklet F1