ALF help

Design help

On the Design pages you enter information about the particular house design and location to perform an ALF analysis on it.

House Zoning

House Zoning

ALF is a single zone model. Thus internal floors/ceilings in multi-storey houses are not considered for heat losses (they are considered, though, for the estimation of thermal mass). It is accepted that this is a limitation of the procedure. However, the inclusion of multi-zone options would increase the complexity of the method.

If it is clear that parts of the building will not be heated at all (i.e. attached garages), the following adjustment can be used: for all the area calculations use only the part of the building which is going to be heated. Adjust the R-value of the internal walls between heated and unheated zones by adding the R-values of the external walls of the unheated zones to the internal wall R-values.

This method is a very coarse adjustment, which does not account for gains and thermal mass in the unheated areas. Also the area of the external walls of the unheated zone is not taken account of.

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 Create an ALF account

Register now to create your free ALF account.

Every user needs to create an ALF account. Creating an ALF account will ensure:

  • Confidentiality for your project.
  • Allow BRANZ to record usage of the ALF tool – BRANZ cannot access any individual projects. Your privacy is assured.

 Contact and Feedback

Contact us at Branz for further information about the ALF 3.2: Annual Loss Factor.