Accredited Details
In order to comply with Part L 2010 regulations, thermal bridging calculations must now be completed for all new dwellings. This is a great help for new buildings as thermal bridging is now accurately modelled for those designs particularly aimed at obtaining a high thermal efficiency.
To assess the level of thermal bridging in a design, we at Green House Calcs will provide a list of the relevent junction codes used in the design, based on the diagram below. A code sheet can then be created relating any junction that is to follow the accredited or enhanced route, to a specific drawn detail. These detail drawings can be found at the bottom of the page or downloaded from the Planning Portal or Energy Saving Trust websites.
There is some debate over the time at which these details should be clarified. Current conventions state that details must be legally provided at 'as-built' stage for the creation of an energy perfrmance certificate (EPC). At Green House Calcs we back the opinion of providing details at design stage to avoid any post construction problems.
The effect of thermal bridging calculations should not be underestimated in their use in achieving good SAP results
Please use the information attached to the links below and our step by step instructions to gain an insight into this now regulated proceedure. Detail drawings of each junction for accredited and enhanced constructions also follow the diagram.
Step 1
Receive a list of junction codes from your assessor and relate them to the document attached below. This document contains a list of all possible junction details, for all construction types.
(ie Cavity wall, timber frame etc).
Download
Step 2
Choose the project construction type from the list below for accredited or enhanced details, and make a note of the relevant detail drawing for each junction used in the project. E.g MCI - GF - 01
Step 3
Inform your assessor
of each detail that will be accredited or enhanced in construction. Default values will be used for those details that are not to be accredited or enhanced, and these will have the value of double the accredited values. BEWARE!
Detail drawings - Accredited details
Introduction
Steel frame - code starts with SFW
Wood frame - code starts with TFW
Masonry cavity (cavity insulation)- code starts with MCI
Masonry cavity (internal insulation) - code starts with MII
Masonry cavity (external insulation) - code starts with MEI
Detail drawings - Enhanced details
Introduction -- (required reading to understand the codes below)
MV-01
MV-02
MV-03
TF-01
TF-02
SF-01