Affordable housing refers to housing for purchase and rental, including social housing, that is appropriate for the needs of very low to moderate-income households. This is generally understood to mean housing that costs no more than 30 per cent of a household’s gross income.

Social housing is affordable housing provided by the government and community sectors to assist people who are unable to afford or access suitable accommodation in the private rental market. It includes public housing, state owned and managed Indigenous housing and community housing. Rents are set as a proportion of household income.

Key worker housing refers to affordable rental or purchase options for workers in essential services who often struggle to afford housing due to their income or the high cost of living in areas close to their employment.

The Australian Housing and Urban Research Institute, defines housing stress as a situation where a household in the bottom 40% of the income distribution pays more than 30% of its income on housing costs.

The most commonly accepted definition of homelessness includes three categories.

Primary homelessness is when people have no conventional accommodation, such as sleeping rough or in improvised dwellings like tents.

Secondary homelessness is when people move often between temporary places, such as emergency accommodation, youth shelters, or couch‑surfing.

Tertiary homelessness is when people live in accommodation below minimum community standards, such as boarding houses or caravan parks.

Medium density housing typologies include single-storey villa developments, duplexes and co-joined dwellings, terrace housing, townhouses, apartment buildings up to six storeys, shop top housing and mixed-use residential developments with commercial tenancies.

High density housing is multiple dwellings on a site that are over six storeys in height. Typical typologies include residential apartment buildings and mixed-use residential developments with commercial tenancies.

‘Bluefield Housing’ is a land definition and an accompanying urban infill housing model which describes co-located housing that integrates new additions with existing homes, looks and feels like single-family housing, but operates financially and legally like a small group of units.

The South Australian government’s definition of ‘co-located housing’ means a group of two or more self-contained dwellings contained on land within the Co-located Housing Overlay that meet the following criteria:

• they each occupy an allotment created under the Community Titles Act 1996;
• they comprise at least one or more established dwellings facing a primary street that may be sensitively altered and / or extended as part of the co-located housing development to accommodate additional dwellings
• they incorporate communal open space that is accessible to all dwellings
• they may also comprise other common
• areas and / or facilities for shared use by all occupants, including:-a common building that includes facilities such as a shared kitchen, dining and / or living facilities, shared laundry facilities, shared carparking

Secondary residences often called a “granny flat” or “ancillary dwelling,” is an additional dwelling on the same site as a main house. They are subject to specific planning rules and regulations within the Hobart Planning Scheme and must be self-contained, have a gross floor area not more than 60m², belong to a single dwelling, and share access, parking, and water, sewerage, gas, electricity and telecommunications connections and meters.

Adaptive reuse is the process of repurposing an existing building for a new function. This not only preserves the history of a site but also makes use of a previous carbon investment in the building stock, thereby reducing embodied carbon. Adaptive reuse can be appropriate for buildings protected by the Tasmanian Planning Scheme’s Heritage Code or listed on the Tasmanian Heritage Register, as well as unlisted buildings with heritage values.

Shop top housing refers to a dwelling that are located above ground floor retail or commercial uses.

Underutilised land can better be understood as either Brownfield of Greyfield:

Brownfield is land that has been previously developed, often for industrial, commercial, or agricultural purposes, and is now disused, underutilised, or potentially contaminated. These sites frequently require decontamination and remediation before redevelopment, bringing them back into beneficial use as residential properties, community facilities, or new commercial ventures.

‘Greyfield’ suburbs feature ‘under-utilised property assets such as privately owned and occupied residential building stock, usually built between the late 1940s and the 1970s, that is failing physically, technologically and environmentally. Typically these suburbs contain energy, water and communications infrastructure in need of regeneration’ together with older, physically run-down community assets, such as tennis and bowling clubs.