Rooming House Conversion Cost Estimator

Rooming House Conversion Estimator

Super Cashflow Developments  ·  Based on South Bay Constructions quotes, Apr–Jun 2026

Property details

Foundation type
Slab roughly doubles bathroom costs
Existing bedrooms
3
Additional bedrooms to create
Via framing new walls in living areas etc.
2

Air conditioning & security

Install air conditioners
~$2,000 per bedroom (2.5kW split system)
Digital smart locks
Each bedroom + entrance + management cupboard

Bathroom works

Replace bathtub with toilet
Stumps ~$10k  ·  Slab ~$18–19k
Convert laundry to bathroom
Stumps ~$11k  ·  Slab ~$19k
Add toilet to ensuite / WIR
~$5–6k depending on plumbing access
Repurpose ensuite as shared bathroom
Open hallway access through WIR — ~$4k

Optional extras

Garage conversion
+2 bedrooms  ·  windows, subfloor, framing (~$32k)
Replace carpet with hybrid flooring
Dining / rumpus areas (~$4k)
Euro laundry relocation
If converting laundry to bathroom (~$3k)

Contingency

Buffer
Recommended 15–20% for sight-unseen quotes

All figures are ballpark estimates based on South Bay Constructions quotes (Apr–Jun 2026). Costs vary by property condition, exact scope, slab vs. stumps, and builder. Always obtain a formal quote before committing.

Super Cashflow Developments  ·  supercashflow.com.au