Platform-Enabled Informality?

Figures & data

Table 1 Australian online housing platforms and rental market segments.

Platform	Listing by	Market segment	Accommodation type
Realestate.com.au	Real estate agent	Diverse: private renter households	Whole properties, houses, and apartments Boarding houses/room rentals/secondary dwellings
Gumtree.com.au	Landlord/owner	Lower-income households seeking private/shared space	Whole properties, secondary dwellings, room rentals, share houses
Flatmates.com.au	Existing resident/head tenant	Individuals/couples/families willing to share	Share houses/apartments
Airbnb.com	Owner/manager	Short-term visitors	Whole properties/private rooms

Figure 1. Summary criteria for classifying informal rental accommodation advertised on Realestate.com.au.

Table 2 Overview of informal housing listings on Realestate.com.au., Gumtree.com.au, Flatmates.com.au, and Airbnb.com, August 2021.

Categories	Sydney	Melbourne	Brisbane
ABS census rental dwellings	657,317	537,865	320,356
ABS census group households^a	76,558	76,606	42,431
SQM rental vacancies (% of total)	19,976 (3)	22,166 (4.1)	4,732 (1.5)
Realestate low-cost informal housing listings	681	1,452	504
Gumtree informal housing listings	1,008	942	247
Gumtree low-cost informal housing listings	333	273	119
Flatmates informal housing listings	2,379	2,548	1,361
Flatmates low-cost informal housing listings	1,945	2,506	1,361
Total informal housing listings	4,068	4,942	2,112
Informal housing listings (% of rented dwellings)	0.60	0.90	0.70
Informal housing listings (% of rental vacancies)	20.40	22.30	44.60
Informal dwellings (Realestate.com) (% of total rental vacancies)	3.41	6.86	10.65
Informal tenures (Gumtree and Flatmates) additional contribution to rental vacancies (%)	16.96	16.49	33.98
Flatmates listings (% of group households)	3.11	3.33	3.21
Airbnb total residential listings	31,990	19,700	5,207
Airbnb entire dwellings	19,380	12,335	3,443
Airbnb private rooms	12,022	6,992	1,718
Airbnb shared rooms	588	373	46
Frequently available Airbnb dwellings ≥ 90 nights per year	9,915	8,795	3,393
Frequently available Airbnb dwellings (% of rental vacancies)	50	40	72

Note: a. The ABS Census regards two or more unrelated adults living together as a group household. Sources: Realestate.com.au, 2021; Gumtree.com.au, 2021; Flatmates.com.au, 2021; ABS, 2022; SQM Research, 2021.

Table 3 Pearson correlation coefficients of informal housing listings versus rented dwellings and group households in three cities.

City	Correlations
	Pearson correlation		Informal housing listings	Rented dwellings	Group households
Sydney	Informal housing listings	Pearson correlation	1	.825*	.881*
		Sig. (two-tailed)		<.001	<.001
		Sample size (N)	449	449	449
Melbourne	Informal housing listings	Pearson correlation	1	.679*	.781*
		Sig. (two-tailed)		<.001	<.001
		Sample size (N)	316	316	316
Brisbane	Informal housing listings	Pearson correlation	1	.495*	.766*
		Sig. (two-tailed)		<.001	<.001
		Sample size (N)	251	251	251

Note: *Correlation is significant at the .01 level (two-tailed). Sources: Realestate.com.au, 2021; Gumtree.com.au, 2021; Flatmates.com.au, 2021; ABS, 2022.

Figure 2. Spatial distribution of total informal housing listings as percentage of rental housing stock in three cities. Source: Derived from Realestate.com.au, 2021; Gumtree.com.au, 2021; Flatmates.com.au, 2021; ABS, 2022.

Figure 3. Composition of informal housing supply on real estate, August 2021. Source: Derived from Realestate.com.au, 2021; Gumtree.com.au, 2021; Flatmates.com.au, 2021.

Table 4 Informal rental accommodation and potential planning responses.

Informal accommodation type	Risks	Potential planning responses
Share home/flat sharing (including room rentals)	Overcrowding Social conflict Insecure tenure	New housing stock designed for share households (storage; privacy; noise attenuation; common spaces) Education on share household rights Standard share house leasehold agreements
Secondary dwelling (compliant with planning and building rules)	Social conflict (with primary residence) Future redevelopment potential foreclosed Informal lease/insecure tenure May be high rental cost	Landscaping; privacy; noise attenuation guidelines Encourage in areas not likely to be needed for more intense redevelopment in future Standardized common tenancy agreements Rental caps/regulations
Secondary dwelling (noncompliant)	Building/health and safety Poor amenity (privacy, esthetic appearance) Burden on local services (traffic, solid waste, waterflow) Social conflict (with primary residence) Informal lease/insecure tenure	Ensure planning system allows legal pathway for diverse/lower-cost housing Education: owners, tenants, building industry Enforcement action
Formal boarding house	May be high rent Not appropriate housing type for families with children	Rental regulation Ensure alternative low-cost housing typologies suitable for families with children, women
Informal boarding house	Fire risks Health/safety risks Social conflicts Insecure tenure	Enforcement Ensure legal pathways for boarding house development/upgrading Support for vulnerable residents (e.g., education, referral services)
Short-term rental accommodation	Loss of long-term rental units Neighbor impacts Health/safety risks of unregulated tourist accommodation	Regulations to prevent loss of rental units Planning regulations/registration to manage noise, privacy, traffic, waste, safety issues

Realestate.com.au. (2021). Website. REA Group.

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Gumtree.com.au. (2021). Website. Gumtree.

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Australian Bureau of Statistics. (2022). 2021 Australian census. ABS.

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SQM Research. (2021). Residential vacancy rates; Region brisbane CBD. https://sqmresearch.com.au/graph_vacancy.php?sfx=®ion=qld%3A%3ASouthern+Brisbane&t=1

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Flatmates.com.au. (2021). Website. REA Group.

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