Part L Glazing

Question

Hi, 
 I have been asked to model glazing that is not within the glass database on Hevacomp (Pilkington glass 8.0mm and 10.8mm thick this is for the purpose of showing compliance with criterion 3 on the BRUKL report. Pilkington have provided datasheets from their spectrum program which gives information on the whole double glazed unit's Light, Energy and performance values. Unfortunately they are unable to provide information on the individual panes at the thicknesses specified for this project. 
 I have been in touch with BRE about this, they advised the following. 
 "If you were using iSBEM, you could input the lighting transmittance, solar energy transmittance, and U-value of the whole glazed unit instead of selecting a type of glazing and frame from the NCM Glazing Database (please see the iSBEM User Guide, which is also available from the UK-NCM website, for further details). These 3 parameters are what the iSBEM interface passes on to the calculation engine (SBEM). Similarly, 3 rd party interfaces approved by DCLG for the purposes of regulatory energy calculations would be expected to pass on these same 3 parameters in the input file they create for the SBEM calculation engine. " 
 Could you advise if its possible to define the glazing for Part L calculations as BRE have described? 
 
 Kind Regards, 
 
 Andrew

Shane Regan · Answer

Hi Andrew, 
 Yes, you just need to enter the manufacturer's figures into the Glazing Properties section, in the top right of the Glazing Data menu. Please see further information here . 
 We would also recommend obtaining Solar Gain Factors from the manufacturer, as these are important should you wish to run any steady state load calcs, such as CIBSE Gain.