Guideline for Developing an Affordable Housing Contribution Scheme | FEBRUARY 2019
including selling commissions, marketing
costs and legal fees; typical developer
margins for profit and risk; site preparation
and construction costs; professional fees,
contingency, financing costs, land finance
costs, and land tax.
With the above data collated, council can
make an informed assumption regarding
the base development value, if the site was
developed to its full potential.
Alternatively, the base development value
could be determined with the existing use
of the site, regardless of maximum
development potential, with the collation
of comparable land sales. For example,
comparable sales data of dwelling houses
of a similar age and lot size. Determining
the base site value through comparable
sales data is especially relevant on sites
which do not allow for residential
development. Sales data can be obtained
by a real estate agent or property value, or
property sales data and site area
measurements can be found within the free
NSW Globe Google Earth data set.
2. Site value with upzoning
Once a council has determined the base
site value, council can calculate the
residual land value of the site with an
upzoning. This is to determine if there is
the potential for it to be viable to
redevelop the site.
In this assessment, council can amend the
proposed built form and previous
assumptions if the proposed upzoning
changes these inputs, for example
originally the site could be developed for
apartment under three storeys and the
proposed upzoning will enable apartment
over three storeys. Council must also
include local infrastructure contributions
and Special Infrastructure Contributions
which will be applied to the development.
Once these inputs have been finalised,
council can make an informed assessment
on whether the proposed upzoning results
in the potential for it to be viable to
redevelop the site.
3. Testing a viable affordable
housing contribution rate
If it is determined that there is potential for
it to be viable to redevelop the site,
councils can then test an affordable
housing contribution rate that can be
applied to the site in a development
consent, without losing the potential for it
to be viable to redevelop the site. The
affordable housing contribution rate will be
tested as a percentage of gross floor area
that the developer of the site would be
required to contribute to affordable
housing units. The percentage of floor
space could then be equivalised as a
monetary contribution, if a council choose
to levy affordable housing contributions as
a monetary contribution or in part as a
monetary contribution.
In testing a viable affordable housing
contribution rate, there are key inputs or
important variables that could be tested to
understand and optimize the project
outcomes. These are the affordable
housing contribution rate, the local
infrastructure contribution, Special
Infrastructure Contribution and maximum
floor space ratio.