Rooming House Feasibility Study — The Checklist We Run Before a Client Buys

A rooming house feasibility study is the discipline that separates the conversions that hit their numbers from the ones that quietly bleed capital. The headline economics of the Melbourne rooming house strategy are attractive — across the 48 client rooming house conversions in our published dataset with offer dates between October 2023 and September 2025, the mean gross yield measured against total cost including conversion was 6.96% — but that figure is a survivor statistic: every one of those properties passed a structured feasibility work-up before purchase, and plenty of candidates that looked similar on a listing page did not.

I am Steven Jin, Chief Acquisitions Officer at PremiumRea, and this is the eight-step feasibility checklist we run as a Melbourne buyers agent on every rooming house candidate before a client commits: zoning and planning overlay check, the floorplan test, the Class 1b threshold test, conversion cost estimation, room-rent evidence gathering, the total-cost yield math, the council registration timeline, and sensitivity analysis — closing with the go/no-go criteria we actually apply. It is written to be usable: an investor working alone can run a rough version of every step. The strategy background — legislation, councils, risks — lives in our rooming house hub guide; this article is purely the pre-purchase method. All results quoted are historical figures from settled client transactions, not a forecast of what any future property will do.

Step 1 — Zoning and planning overlay check

The first gate is planning, because no other step matters if the site cannot lawfully operate as a rooming house.

Zone. Confirm the property's zone on the free Victorian planning property report (planning.vic.gov.au). Most candidates sit in the General Residential Zone or Neighbourhood Residential Zone. The zone itself rarely prohibits a small rooming house outright, but it frames what the council can require.

Overlays. The same report lists overlays, and these are where candidates die: a Heritage Overlay can make the building works and any external changes permit-intensive; a Special Building Overlay or flood-related overlay complicates building permits; bushfire-related overlays add construction requirements. None is automatically fatal — each adds cost, time and refusal risk that must be priced.

Council posture. The same floorplan in two different municipalities can face a routine approval in one and an effective wall in the other. The permissive-versus-restrictive council mapping is covered in the hub guide, and corridor-level detail is in our suburb-by-suburb rooming house ranking at best suburbs for rooming house investment. At feasibility level, the check is simple: does this council have registered rooming houses operating today (Consumer Affairs Victoria's public register answers this), and does its website document a permit pathway or a hostility?

Output of step 1: a yes/no on planning viability plus a list of overlay-driven cost and time additions to carry into steps 4 and 7.

Step 2 — The floorplan test: 4-5 compliant rooms plus shared space

The floorplan test asks one question: can this building yield four to five compliant resident rooms while keeping adequate shared space, without structural surgery?

The standards that bind, from the Victorian rooming house minimum standards (summarised in plain English on our rooming house rules page): a room occupied by one resident must be at least 7.5 square metres, a shared room at least 14 square metres; residents need adequate bathroom and toilet provision (councils commonly apply a ratio of one bathroom per several residents and in practice expect two bathrooms above five residents); and the kitchen, laundry and living provision must serve the resident count.

What we look for on the plan:

• Four genuine bedrooms plus one convertible space — a study, formal lounge or oversized dining area that can become room five with a partition and a door, while still leaving a living/dining area for residents. A house that yields five rooms only by consuming every shared space fails: it will rent poorly and register badly.
• Bedroom sizes with margin. Rooms at 7.6 square metres pass on paper and fail in the market — small rooms sit vacant. We want most rooms at 9-plus square metres.
• Bathroom geometry. Is there a second bathroom, or a laundry/storage space where one can be added at reasonable cost? This single variable moves the conversion budget by $15,000-$35,000.
• Separation of quiet and shared zones. Bedrooms clustered away from the kitchen/living area produce fewer resident conflicts and better retention.

A useful screening heuristic from our work: 1990s-2000s 4-bedroom suburban stock of 160-220 square metres converts well; compact 3-bedroom stock under about 130 square metres almost never yields five compliant rooms without an extension, which changes the economics entirely.

Step 3 — The Class 1b threshold test

Every candidate gets tested against the National Construction Code Class 1b limits: not more than 12 residents ordinarily in occupation, and total floor area not exceeding 300 square metres. Inside both limits, the conversion proceeds at residential scale; outside either, the building is Class 3 — commercial residential accommodation — and the compliance cost jumps to a level that kills house-scale feasibility (rarely under $250,000 in the projects and quotes we have reviewed).

For a 4-6 room conversion of a standard suburban house this test almost always passes, but the step exists because the failures are expensive and avoidable: large two-storey homes flirting with the 300 square metre line once a garage conversion is counted; plans that add a bungalow or convert outbuildings and drift the resident count upward; or an operating model that contemplates couples in multiple rooms, pushing residents past what the facilities support even while staying under 12.

The step also fixes the compliance route: a pass means the project is a Class 1a to Class 1b change of use through a registered building surveyor — building permit, staged inspections, final sign-off. We cover the whole classification topic, including the fire-safety stack of interconnected smoke alarms, key-free egress and extinguisher provision, in our dedicated Class 1b guide. At feasibility level, the output is binary plus a note: pass/fail, and any features (floor area near the line, extension plans) that need the surveyor's eyes before an offer.

Step 4 — Conversion cost estimate

We estimate conversion cost from a range table, then tighten it with trade quotes during due diligence. The ranges we currently use for a 5-room Class 1b conversion of a standard 4-bedroom house, consistent with the fuller breakdown in the hub guide:

• Building permit, surveyor and reclassification: $4,000-$8,000
• Fire-safety system (interconnected alarms, separation works where required, compliant egress hardware): $25,000-$45,000
• Fifth-room conversion (partition, door, electrical, light/ventilation compliance): $8,000-$18,000
• Bathroom upgrade or second bathroom: $15,000-$35,000
• Kitchen capacity works: $5,000-$12,000
• Electrical upgrade: $4,000-$10,000
• Emergency lighting/egress items where required: $2,000-$6,000
• Certification and final inspection: $2,500-$5,000
• Furniture across five rooms: $8,000-$15,000
• Contingency at 10-15 per cent

Realistic all-in range: $80,000-$150,000, with building era the biggest driver — newer stock lands low, 1960s-70s stock lands high. As a cross-check against real outcomes: across the 48 rooming conversions in our dataset settled between October 2023 and September 2025, mean conversion spend ran $80,000-$89,000 depending on suburb — squarely in the lower-middle of the estimating range, reflecting that the feasibility process itself steers clients toward stock that converts economically.

Feasibility rule: carry the midpoint plus contingency into the yield math, not the optimistic end. A study that only works at $80,000 is a study that fails.

Step 5 — Room-rent evidence

The revenue line of the study must be evidence, not aspiration. We build it three ways and take the conservative reading:

1. Live room listings in the same suburb and adjacent suburbs — the room-by-room rental platforms and general listing portals show asking rents for furnished rooms with bills included. We log 10-20 comparables: room size, inclusions, distance to transport, asking rent.
2. Operating evidence — where we or our property-manager network run rooming houses in the corridor, actual achieved rents and vacancy patterns beat asking-rent data. Asking rents run optimistic; achieved rents are the number.
3. The demand base — proximity to industrial employment, hospitals, TAFEs and universities, and train lines is what fills rooms at listed rents. A corridor can show attractive asking rents on thin listing volume; we want depth of demand, not a high number on two listings.

As context for what the model should look like when it is right: across our 48 client rooming conversions with offer dates October 2023 to September 2025, the mean achieved post-conversion rent was $1,146 per week per property, with a median of $1,150 — for predominantly 5-room configurations, that implies achieved room rents clustering in the low-to-mid $200s per week. A feasibility study assuming $320 per room in a corridor where the evidence shows $230 is not a study; it is a wish.

Output of step 5: a per-room rent figure with comparable evidence attached, and a full-occupancy weekly total to feed step 6 — which will immediately be haircut for vacancy.

Step 6 — The yield math: a worked example

Now the arithmetic, on a composite example built deliberately around our dataset means so the numbers are honest rather than promotional. Historical context first, with the full qualifier: across the 48 rooming house conversions in our client dataset with offer dates from October 2023 to September 2025, the mean gross yield measured against total cost including conversion was 6.96%, the median 6.94%, and the range 5.5% to 8.44% — where yield is annualised weekly rent divided by purchase price plus conversion spend. For comparison, across all 345 purchases in the same dataset (offer dates January 2023 to September 2025), the mean gross yield on the same total-cost basis was 5.90% and the median 5.77%. These are settled historical results, not a forecast.

The worked example, close to the dataset means (mean purchase across the 48 conversions: $776,804):

• Purchase price: $780,000 (4-bedroom house, permissive council, floorplan passes step 2)
• Conversion spend: $85,000 (midpoint estimate, step 4)
• Total cost basis: $865,000
• Transaction costs (stamp duty, conveyancing, inspections): approximately $43,000 — tracked separately below, because the dataset yield convention uses purchase-plus-conversion as denominator
• Evidenced room rent: 5 rooms at $230 per week = $1,150 per week at full occupancy (step 5 evidence)

Gross yield on total cost: $1,150 x 52 = $59,800 annual rent; $59,800 / $865,000 = 6.91% — sitting right at the dataset median of 6.94% for the 48 conversions (Oct 2023-Sep 2025, yield on purchase plus conversion), which is the point: a sound study lands near the middle of the observed range, not at its top.

Toward net: apply 92-95 per cent occupancy, specialist management at 8-12 per cent of collections, owner-paid utilities and internet at $100-$200 per week, insurance, council registration and maintenance — the same deductions detailed in the hub guide — and gross in the high 6s becomes net in the mid 5s on total cost. If the study needs full occupancy and self-management to clear your hurdle, it fails.

Step 7 — Registration timeline and sensitivity analysis

Timeline. The study must fund the gap between settlement and first rent. A typical sequence in a permissive council: building permit design and issue (4-8 weeks), conversion works (8-14 weeks), final surveyor sign-off (1-3 weeks), council prescribed-accommodation registration and any inspection (2-6 weeks), with the operator licence under the Rooming House Operators Act 2016 progressed in parallel (allow several weeks). End to end, four to seven months from settlement to first resident is the realistic planning window — during which the property produces no room income but full holding costs. At roughly $1,000-$1,300 per week of interest and outgoings on the worked example's numbers, a six-month conversion window is $26,000-$34,000 of holding cost that belongs in the project budget.

Sensitivity analysis. We stress the worked example on three axes:

• One room vacant for a full year: 4 x $230 x 52 = $47,840; on $865,000 that is 5.53% gross — inside the dataset's observed range (5.5%-8.44% across the 48 conversions, Oct 2023-Sep 2025) but at its floor. The deal must remain holdable, not comfortable, at this level.
• Conversion overrun of $20,000: denominator rises to $885,000; gross yield at full occupancy falls to 6.76%. Painful, survivable.
• Both at once: $47,840 / $885,000 = 5.41% gross — below the observed floor. If the client cannot hold the property at this level on their income, the deal is too tight, whatever the base case says.

A feasibility study without sensitivity rows is a brochure. The base case tells you what you hope; the stressed case tells you whether you can stay in the deal long enough for the base case to reassert.

Step 8 — Go/no-go criteria

We reduce the study to explicit criteria, applied in order. A candidate proceeds only if all pass:

1. Planning: zone and overlays workable; council has an operating rooming house population and a documented pathway.
2. Floorplan: four to five compliant rooms with shared living space intact and most rooms at 9-plus square metres.
3. Classification: clean Class 1b pass with margin on both thresholds.
4. Cost: conversion estimate at midpoint-plus-contingency keeps total cost inside budget, with the $80,000-$150,000 range respected rather than argued down.
5. Revenue: room rents evidenced by comparables and operating data, not asking-rent optimism.
6. Yield: gross yield on total cost at evidenced rents lands in the observed band — as context, 5.5% to 8.44% across the 48 conversions in our dataset (Oct 2023-Sep 2025, yield on purchase plus conversion) — with the client's own hurdle cleared at 92-95 per cent occupancy under specialist management.
7. Stress: the deal is holdable with one room vacant for a year plus a $20,000 overrun.
8. Finance and timeline: the funding plan covers purchase, cash conversion, and four to seven months of holding cost — with both loan legs mapped with a licensed broker as covered in our rooming house finance guide.

In practice, roughly two of every three candidates that reach a full work-up fail at least one criterion — most often floorplan (step 2) or evidenced rent versus price (step 6). That failure rate is the method working. The 48 conversions in the dataset averaged 6.96% gross on total cost (Oct 2023-Sep 2025) precisely because the candidates that would have dragged the average down were never bought. If you want this run on a specific property — or want the corridor short-list before you start searching — the suburb ranking and a strategy call are the two places to start.