In the past, understanding how to meet the requirements of Building Regulations for thermal insulation was relatively straightforward. A table would tell you the U-value that needed to be achieved for a particular floor, wall or roof and the manufacturer could then tell you what thickness of insulation you needed to achieve that value.
As green issues and the threat of global warming have come to the top of the agenda, however, the approach has changed and the requirements have not only become tougher, but also harder to put into a simple formula. The current Part L of the Building Regulations (Conservation of Fuel and Power) came into effect last year and represents the Government’s response to the EU’s Energy Performance of Buildings Directive. It applies to all new buildings – dwellings and commercial – as well as building work on existing buildings. The new requirements mean developers have to use more energy saving insulation, more efficient boilers and low or zero carbon systems to demonstrate compliance.
PIR based insulation boards offer many advantages in meeting these requirements as they have a high thermal insulation factor per unit mass and an extremely long performance life. Their light weight means they can be easily used with modern construction methods, while their durability means that the building performs to the required level of energy efficiency throughout its life – without the need for resource-consuming replacements.
On new buildings the new Part L sets overall performance standards rather than laying down particular ways of achieving them. The old Elemental Method and Target U-Value approach of determining whether a building is compliant are no longer allowed.
Every new building now has to achieve a Target CO2 Emission Rate (TER) expressed in mass of CO2 per unit floor area emitted by all the internal heating, hot water, ventilation and fixed lighting. This is calculated using either the Government’s Standard Authorised Procedure (SAP 2005) for dwellings smaller than 450m², or the Simplified Building Energy Model (SBEM) for larger dwellings and commercial buildings. Scottish Building Regulations allow a U-Value approach to determining the TER for a notional building and differ in some of their target levels. All BRE approved SAP software includes a ‘Scotland’ option that allows for this.
EcoTherm appreciates that the removal of the old step by- step approach means that it is much harder to know how to comply. To help our customers meet these new requirements we are pleased to offer our technical advice, and on larger projects we can also carry out some of the TER calculations for you.