PartL2(2013-2014)ApacheSim

 

This document covers both ‘Part L2 (2013) – England’ and Part L2 (20141) – Wales.  As such, we make reference to ‘Part L2(2013-2014) ApacheSim’ which covers both regulations.  Where items are specific to a particular regulation mode, we shall state this.

 

Part L2(2013-2014) ApacheSim is a facility within the VE Compliance View which provides the means to test compliance with Part L2 of the 2010 Building Regulations (2013 edition, in force from 6 April 2014) and to generate Energy Performance Certificates (EPCs) for non-domestic buildings within the same framework, using a dynamic simulation model (DSM). An alternative route to compliance  based on BRE’s Simplified Building Energy Model (SBEM) is also provided within VE Compliance, and documented in other user guides (for example PartL2(2013)VE-SBEM.pdf).

Part L2 (2013-2014) ApacheSim applies to new buildings other than dwellings in England and Wales.

Data for the Part L2 (2013-2014) ApacheSim analysis is taken from the Virtual Environment model, supplemented where necessary by inputs specific to the requirements of Part L2 (2013-2014).

This user guide covers software facilities in the Virtual Environment for testing compliance with the 2013 edition of The Building Regulations and for generating EPCs within the same framework.

The requirements of The Building Regulations 2010, Part L2 (2013-2014 England/Wales additions) as applied to new buildings are set out in Approved Documents L2A^[1]. These documents (England and Wales) should be consulted for guidance on submissions for Part L2 compliance.

Details on what an approved document is and how it should be used is set out in the introduction:

 

The broad requirements of L2 are set out in the Requirement section of Approved Document L2A[1] (referred to in this document as ‘L2A’). They cover:

 

The detailed requirements are outlined in Section 1: The Requirements, under the heading Demonstrating compliance. Five criteria must be satisfied (paragraph numbers refer to L2A):

 

 

L2A should be consulted for details of special considerations and exemptions applying to particular classes of buildings.

Some of the requirements of Part L2 cannot be tested in software (Criteria 4 and 5 fall into this category).

The requirements tested by the software are Criteria 1 to 3, which are implemented in the software as follows.

 

In accordance with principles set out in L2A^[1] and the NCM Modelling Guide^[3], the BER and TER values are obtained from the simulated carbon dioxide emissions of two buildings.

The ‘actual building’, which forms the basis of the BER calculation, is the building as designed, but subject to standard operating conditions dictating levels and patterns of occupancy, internal gain and minimum ventilation.

The ‘notional building’, which forms the basis of the TER calculation, is a version of the actual building modified in accordance with rules relating to glazing area, insulation, system efficiency and other factors. The notional building is also subject to the standard operating conditions.

Both buildings are simulated over a typical year using standard weather data appropriate to the building location. Results are automatically fed into the BRUKL compliance calculator provided by BRE.

The standard operating conditions are functions of the building type and the activities occurring within each room. They are laid down in the National Calculation Methodology (NCM) Modelling Guide^[3]. It is important to note that the stipulation of standard operating conditions for L2 (2013-2014) compliance calculations means that simulation results as calculated for L2 (2013-2014) will in general be different from those calculated for the ‘real’ building (for example in the Apache View).

 

Criterion 2 imposes constraints on U-values and other aspects of building and system performance.

Limiting fabric standards (U-values) for fabric elements are stated. The software applies checks for compliance with this requirement before performing the actual and notional building simulations.

Limiting services efficiencies are also laid down in the following areas:

·       Controls

·       System efficiencies

·       Energy Meters

·       Centralised switching of appliances

 

Other limiting services efficiencies are also suggested in the DCLG Non-Domestic Building Services Compliance Guide (2013 edition) and include;

·       Heating and hot water service systems

·       Cooling plant

·       Air handling plant

·       Insulation of pipes, ducts and vessels

·       Lighting

 

This criterion seeks to limit the solar gains to spaces during the summer period with the aim of

·       Reducing the need of air-conditioning, or

·       Reducing the installed capacity of any air-conditioning system that is installed.