The Honest Answer About Mould Removal Costs
The honest answer to “how much does mould removal cost?” is: it depends significantly on what you’re actually dealing with. A bathroom ceiling patch and a post-flood Lismore wall cavity problem are both “mould removal” — but they sit at completely different ends of the cost spectrum.
This guide provides transparent price ranges for every type of mould removal job we handle in Northern Rivers NSW, along with the factors that drive costs up or down within each range. Our goal is to give you enough information to understand what your situation is likely to involve before you contact anyone.
Prices are indicative for 2025–2026 and include GST. Northern Rivers costs are specific to this market — they will differ from Sydney or Melbourne pricing.
Mould Inspection Costs
Before remediation, most situations benefit from a professional inspection. Inspection costs are generally credited against any subsequent remediation work.
| Inspection Type | Cost Range |
|---|---|
| Basic visual inspection (small property, single area) | $250 – $350 |
| Full property visual inspection with moisture mapping | $350 – $550 |
| Inspection + single air sample (lab analysis) | $450 – $700 |
| Inspection + multiple air samples | $550 – $950 |
| Thermal imaging inspection | Add $150 – $300 to any inspection |
| Pre-purchase mould inspection | $350 – $600 |
| Post-remediation clearance testing | $300 – $550 |
What drives inspection costs up: Larger properties, multiple suspected mould locations, post-flood investigation requiring thermal imaging and air sampling, need for formal reports for insurance or legal proceedings.
What drives inspection costs down: Small single-area jobs, properties where the mould is clearly visible and the scope is self-evident.
Surface Mould Treatment Costs
Surface mould treatment applies professional-grade antimicrobial products to mould on non-porous or semi-porous surfaces. This is appropriate where mould has not penetrated the substrate.
| Treatment Type | Cost Range |
|---|---|
| Single bathroom ceiling (surface treatment) | $380 – $800 |
| Single bathroom full surface treatment (walls, ceiling, grout) | $500 – $1,100 |
| Kitchen surface treatment | $400 – $850 |
| Laundry surface treatment | $350 – $700 |
| Multiple room surface treatment | $700 – $2,000 |
Important caveat: Surface treatment is only appropriate where the mould is genuinely surface-level. A professional assessment is required to confirm this before treatment. Surface treatment applied to structural mould — mould that has penetrated the substrate — will not resolve the problem.
Bathroom Ceiling Mould Removal
The most common mould call in Northern Rivers.
| Scenario | Cost Range |
|---|---|
| Small patch (< 0.5 m²) surface treatment | $380 – $600 |
| Standard bathroom ceiling (surface mould) | $450 – $800 |
| Bathroom ceiling with structural penetration (plasterboard removal and replaster) | $800 – $2,000 |
| Full bathroom mould treatment including grout resealing | $700 – $1,800 |
| Two bathrooms | $700 – $2,200 |
Full Structural Mould Remediation Costs
Full remediation to IICRC S520 standards is required when mould has penetrated porous building materials.
| Scope | Cost Range |
|---|---|
| Single room remediation (plasterboard removal, treatment, clearance) | $1,000 – $3,500 |
| Two room remediation | $2,500 – $6,000 |
| Three to four room remediation | $4,000 – $10,000 |
| Full property remediation (4+ rooms) | $7,000 – $18,000 |
| Post-remediation clearance testing (included or separate) | $300 – $550 |
Cost factors:
- Severity of penetration — how deeply mould has entered building materials
- Materials affected — plasterboard (cheaper to replace) vs original hardwood (more care required)
- Access constraints — tight spaces, multi-storey, heritage structures
- Rebuild inclusion — whether our scope includes replastering (some clients prefer a separate plasterer)
Post-Flood and Water Damage Mould Remediation
Post-flood mould remediation in Lismore, Casino, Murwillumbah, and Ballina is a specialist service with costs reflecting the contamination category and typically larger affected areas.
| Scope | Cost Range |
|---|---|
| Concealed mould investigation (thermal + air sampling) | $450 – $900 |
| Single room post-flood wall cavity remediation | $1,500 – $4,500 |
| Multi-room post-flood remediation (3–5 rooms) | $5,000 – $15,000 |
| Full property post-flood remediation | $8,000 – $40,000+ |
| Category 3 water (highest contamination) add premium | +20–40% to standard remediation |
Note on the upper range: The $40,000+ upper range for full property post-flood remediation reflects the most severely affected Lismore homes — those with whole-of-property wall lining removal, structural drying required before rebuild, and extensive contamination documentation for insurance. Most single-story homes that were flooded to ceiling height in one or two rooms will sit in the $8,000–$15,000 range.
Subfloor and Roof Void Mould Costs
| Service | Cost Range |
|---|---|
| Subfloor inspection (access and assessment) | $250 – $450 |
| Subfloor mould treatment (standard elevated home) | $700 – $2,500 |
| Subfloor treatment (large or complex, post-flood) | $2,000 – $6,000 |
| Roof void mould treatment (standard) | $800 – $2,800 |
| Combined subfloor and roof void treatment | $1,500 – $6,000 |
Mould Fogging and Antimicrobial Treatment
| Service | Cost Range |
|---|---|
| Single room fogging (bathroom/laundry) | $200 – $400 |
| Unit or apartment (2 bedrooms) | $350 – $600 |
| Standard house (3 bedrooms) | $450 – $750 |
| Larger property (4+ bedrooms) | $600 – $1,000 |
| Quarterly maintenance programme (per visit) | $300 – $600 |
Northern Rivers Location Price Variations
Mould removal costs vary somewhat by location within Northern Rivers, reflecting property values, travel, and typical job complexity.
| Location | General Price Tendency |
|---|---|
| Byron Bay | Upper end of range — premium property market, holiday rental documentation requirements |
| Lennox Head | Upper-mid range — coastal premium, short-term rental documentation |
| Ballina | Mid range — mix of residential and investment properties |
| Bangalow | Mid range — hinterland, older homes, subfloor component common |
| Mullumbimby | Mid range — older housing stock, subfloor component very common |
| Lismore | Mid to upper range for flood-affected properties — complexity and scope |
| Murwillumbah | Mid range — post-flood properties at upper end |
| Casino | Lower-mid range — lower property values, somewhat simpler jobs on average |
What Is NOT Worth Trying to Save Money On
The initial assessment. A professional assessment before remediation is the difference between treating the right problem and treating the visible symptom. Skipping assessment and going straight to surface treatment on a structural mould problem is money wasted.
The remediation standard. IICRC S520-protocol remediation costs more than a “clean and treat” approach — but it works. Surface cleaning of structural mould does not resolve the problem; it delays it while potentially making the overall cost higher when the mould returns.
Clearance testing. Post-remediation clearance testing is what tells you the job worked. For insurance claims, it’s essential. For your own peace of mind, it’s worth every dollar.
Frequently Asked Questions
Why is the price range so wide? How do I know what I’m likely to pay? The range reflects the genuine variability of mould problems. A standard bathroom ceiling treatment is straightforward; a post-flood wall cavity remediation in a three-bedroom Lismore home is a completely different scope of work. The only way to get an accurate price for your situation is an on-site assessment — which is why we provide written scopes and fixed pricing before any work begins.
Is mould removal covered by home insurance in NSW? Mould as a standalone condition is typically not covered. Mould that is a consequence of a covered event — flood, storm, burst pipe — may be covered as part of that claim. Coverage is policy-specific. We provide documentation to support insurance claims; the determination of coverage is the insurer’s role.
Can I get a ballpark quote without an inspection? For very clearly defined, simple jobs (one small bathroom ceiling patch, no other symptoms), we can sometimes give indicative pricing from photos and a description. For anything involving suspected structural mould, post-flood history, or a musty smell with no visible source — we need an on-site assessment to give you an accurate quote.
Do you charge for the inspection if I then proceed with remediation? The inspection cost is credited against the cost of remediation work we carry out at the same property. Net cost of inspection for properties that proceed to remediation: zero.
Get an Accurate Quote
The best way to know what your Northern Rivers mould removal will cost is a professional assessment. Request a Free Quote — we provide written scopes and fixed pricing before any work begins, with assessment appointments available within 24 hours across Northern Rivers.