Changes to Part L of the Building Regulations have been introduced in April 2006. Clancy Consulting have held a number of free seminars to raise awareness with clients and professional colleagues to explain the significant changes to the design methodology of buildings and their engineering services.
Fundamentally, new buildings and their services must now be designed and analyzed as a “whole” to achieve reductions in overheating, energy use and carbon emissions of between 18% to 28% (depending on the type of building and how it is to be serviced) when measured against the Part L 2002 Building Regulations.
The 4 new Part L sections are:-
Part L1A – Work in New Dwellings
Part L1B – Work in Existing Dwelling
Part L2A – Work in New Buildings other than Dwellings
Part L2B – Work in Existing Buildings other than Dwellings
We believe that the risks with respect to design and build projects could be significant if not handled correctly at the planning stage by the Design Team.
Our principal concern relates to the new requirement for a “report” to be prepared and submitted with the Building Regulation application made by the Architect.
The “report” identifies to Building Control the principal design decisions that have been made by the Design Team with respect to the elevation treatment, for example, shading to glazing, glazed areas, thermal properties of materials and efficiency of the engineering services.
The “report” must also state the carbon dioxide Target Emission Rate (TER) for the building which must be determined by an approved emissions modelling programme to demonstrate compliance with Part L2A.
The modelling programme will analyze the thermal performance of the building and its services by considering such items as:-
• Internal summertime temperatures
• Pattern of use/occupation
• Orientation
• Location
• Glazing to wall ratios
• Shading
• Building services system types/efficiency (mechanical and electrical)
• Fabric thermal performance
• Air leakage rate
Our opinion is that the thermal modelling and systems analysis must be done as part of the Planning Application stage and not left to the Building Regulation stage, because, not to do so carries a significant risk that major changes may be required to the building elevations/fabric and services solutions to gain compliance with Part L2A.
In conclusion, the new regulations introduce significant challenges to reduce energy consumption, they also introduce risks for the unwary client, consultant or design and build services contractor, because buildings can no longer be designed in isolation of their engineering services and expect to comply with the new regulations.
If you require a demonstration of our thermal modelling capabilities, please contact Tom Edge at our Manchester office or via e-mail.