Mould Resistant Coating Costs SA 2026 - Get Free Quotes

Mould Resistant Coating Costs in South Australia

Mould resistant coatings across South Australia generally cost $18 to $40 per square metre. By job that is $250 to $600 for a single ceiling, $450 to $1,100 for a bathroom, $400 to $900 for a laundry or ensuite and $4,000 to $10,000 for a whole house upgrade, with treatment of existing growth adding $200 to $800 per room before any painting starts. Now the part that matters more than the price. That figure is the smallest part of most mould jobs, which is the point this page keeps returning to.

A mould resistant coating contains additives that inhibit mould growing on the surface of the paint film. That is the limit of what it does. It does not remove existing mould, it does not stop moisture reaching the wall, and it does not address whatever is making the room damp enough for mould to grow in the first place. Paint it over a live problem and the problem continues underneath.

This is not a criticism of the products, which do their job well within their limits. It is a criticism of how they are sold, because a homeowner with mould on a bathroom ceiling is frequently offered a tin of mould resistant paint as a solution when what they actually need is an exhaust fan that vents outside. In South Australia the cause is most often condensation rather than a leak. Adelaide winters bring cold nights, houses get closed up, and moisture generated inside by showering, cooking, drying clothes and breathing condenses on the coldest surfaces it can find. In older homes with solid masonry walls and no insulation, those surfaces are the external walls themselves.

This page covers what the coatings do, the sequence that works, the causes, condensation, evaporative cooling, ventilation, treating growth, product selection, where mould shows up, health and rental responsibilities. General interior work is covered in the SA interior painting guide and broader background in the SA painters guide. It also explains why the paint should be the last thing you buy rather than the first. Read the sequence section before pricing anything, since it decides what you actually need.

What These Coatings Actually Do

Understanding the mechanism makes the limits obvious. A mould resistant paint carries biocides or fungicides distributed through the film. When mould spores land on the coated surface, those additives inhibit them from establishing and growing. The coating is defending its own surface.

Three limits follow directly from that. It cannot help with mould that is growing behind the surface, inside a wall cavity, under a floor or above a ceiling. It cannot help where liquid water is arriving, because a leak overwhelms any surface additive. And the additives deplete over time, leaching out gradually with washing and exposure, so the protection weakens across the life of the coating rather than lasting indefinitely. There is one more point that catches people. These coatings must be applied to a surface that is already clean and free of mould, because painting over live growth traps it, feeds it with the coating's own binders in some cases, and it reappears through the new film within months.

Used correctly, as the final layer after the cause is fixed and the surface is treated, they are useful and worth the premium in wet areas. Used as a substitute for fixing a problem, they are money spent on a delay. Used as a substitute for fixing the cause, they buy months rather than years. That distinction decides whether the money is well spent.

The Sequence That Works

Five steps in this order, and skipping any of them is why mould comes back. Each step depends on the one before it, and the order is not negotiable. Contractors who propose starting at step five are selling paint rather than solving a problem. The sequence below is what a competent operator will follow.

Find the moisture source. Condensation, a leak, rising or salt damp, or inadequate ventilation. This is diagnostic work and it is the step most often skipped because it is the least satisfying. Mould inspection services do exactly this where the cause is not obvious. Fix it. A properly ducted exhaust fan, a shower rectified, insulation added to a cold wall, a downpipe reconnected, or damp treated in the masonry.

Until this happens nothing else lasts. Kill and remove the existing growth. Treatment rather than a wipe over, using a suitable product, with the residue removed rather than left on the surface. Let it dry properly. A surface that looks dry can still hold moisture, and coating a damp substrate causes adhesion failure regardless of what the product claims. Adelaide's dry air helps here, and a few days with ventilation makes a real difference.

Then coat. A suitable primer where the surface has been stained or damaged, then the mould resistant finish. A quote that covers only step five is pricing a repaint, not a solution, and it is entirely reasonable to ask a contractor what they think the cause is before you accept it. Allow the manufacturer's full recoat interval between coats rather than rushing the second.

Why Adelaide Homes Get Mould in Winter

South Australians are often surprised to find mould in a state known for dry summers, and the confusion comes from thinking of mould as a wet weather problem. It is a condensation problem, and condensation is at its worst in a cool, closed-up house in July rather than in a humid one in February. The mechanism is simple enough. Warm indoor air holds moisture from cooking, showering, drying clothes and breathing, and when that air meets a cold surface it releases that moisture onto it. Any surface cold enough becomes a condensation point, and mould grows wherever moisture sits for long enough.

Solid masonry walls are the reason this bites harder in older Adelaide housing. A double brick or stone wall with no cavity and no insulation runs close to outdoor temperature, so in a Hills winter the inside face of a south-facing wall can sit several degrees below the room air. Plasterboard on a battened cavity behaves quite differently. That is why the pattern is so consistent across the state. Mould appears in the corners of external walls, behind wardrobes pushed against them, around window reveals and on ceilings below an uninsulated roof space, and those are precisely the coldest surfaces in the room.

Post-war Housing Trust stock through the northern and western suburbs is heavily represented for the same reason. Solid construction, minimal insulation and small windows that rarely get opened in winter produce exactly the conditions mould needs, and the occupants are often heating one room rather than the house. Understanding this changes what you buy. A mould resistant coating on a cold wall slows growth on the paint film, but the wall is still cold and the air is still carrying moisture. Fixing the temperature or the moisture is what actually solves it, and the coating is insurance on top.

Why Mould Grows

Mould needs moisture, a surface and moderate temperature. Two of those you cannot change, so moisture is where the work goes. Condensation is the most common cause in South Australian homes and it gets its own section below. Temperature and surface you largely cannot change in an existing house, so moisture is where the work goes.

Inadequate ventilation runs a close second. A bathroom with no exhaust fan, or one that runs for two minutes and stops, holds shower moisture in the room where it condenses on the ceiling. Laundries and kitchens do the same at lower intensity. Leaks are the obvious cause and the least common of the three. A failed shower waterproofing membrane, a roof leak, a plumbing leak in a wall, or a blocked gutter overflowing behind a wall all produce localised mould that is usually accompanied by staining. Shower rectification handles the most frequent of those.

Rising damp and salt damp introduce moisture into masonry from below, which appears as damage in a band above floor level and can support mould on the internal face. Salt damp treatment addresses the cause. Then there are the habits that add moisture to indoor air without anyone thinking about it. Drying washing indoors through winter, which is common in Adelaide's wet months.

Unflued gas heaters, which produce water vapour as a combustion product and are still found in older South Australian homes and rentals. Long showers with the door closed and no extraction. And keeping the house sealed on cold days, which is understandable and which traps everything inside. Replacing an unflued gas heater removes a moisture source and a combustion risk at the same time.

Condensation in Adelaide Winters

This is the South Australian mould story and understanding it explains most domestic cases here. Warm air holds more moisture than cold air. When warm humid indoor air meets a cold surface, it cools at that surface, and the moisture it can no longer hold condenses out as liquid water. That is why windows run with water on a July morning.

Adelaide's Mediterranean climate gives us wet, cool winters with cold clear nights, which is precisely the condition that produces this. The coldest surfaces in a house are single glazed windows, external wall corners, the wall behind a wardrobe where air does not circulate, and any uninsulated external wall. In much of Adelaide's older housing stock, including solid double brick and stone homes across the inner and middle suburbs and the post-war Housing Trust stock, external walls have no cavity insulation at all and they get distinctly cold. Mould then grows on those cold spots because that is where the water is.

The pattern is recognisable. Mould in room corners on external walls, behind furniture pushed against an external wall, inside wardrobes on external walls, around window reveals and behind curtains, and along the cornice line on the south side of the house. South facing rooms are worst because they receive the least sun. The remedies are ventilation, heating and insulation rather than paint. Extraction where moisture is generated, some air movement so humid air does not sit against cold surfaces, and warming those surfaces through ceiling insulation or double glazing where that is practical. Condensation control specialists assess the whole picture.

Evaporative Cooling and Indoor Humidity

This one is specific to South Australia and it surprises people. Evaporative air conditioning is extremely common here because it suits a dry climate and runs cheaply. It works by drawing outside air through wet pads, and the evaporation cools the air while adding moisture to it. That cooled, humidified air is then pushed into the house. The system depends on that moist air escaping. Evaporative cooling requires windows or doors open to allow continuous airflow through the house and out, which is exactly the opposite of how refrigerated air conditioning is run.

Where a household closes the house up while running evaporative cooling, humidity builds indoors with nowhere to go. Running it with windows or doors open is how the system is designed to work, and closing the house defeats it entirely. That single habit accounts for a surprising share of winter mould in this state. Ask anyone who services evaporative units and they will say the same.

That is not usually enough on its own to cause mould through a dry Adelaide summer, since the air is warm and the surfaces are not cold. The problem arrives in the shoulder seasons and in poorly ventilated rooms, and it compounds anything else going on. A bathroom with no extraction in a house running evaporative cooling with the windows shut is a damp room. The practical points are straightforward. Run evaporative cooling with windows open as the system is designed to work, have the unit serviced so the pads and bleed system function correctly, and turn it off rather than leaving it running on damp humid days when it achieves little cooling and adds moisture. Evaporative cooling technicians handle servicing.

Fans and the Roof Space Mistake

If you read one section on this page, read this one, because it describes the single most common and most fixable fault in South Australian homes. A bathroom exhaust fan is supposed to move moist air out of the building. In a very large number of houses, it does not. It discharges into the roof space instead. The fan is doing its job as far as the bathroom is concerned, and every shower is now delivering warm moist air into the ceiling cavity, where it condenses on the underside of the roof, on rafters and on the top of the ceiling insulation. The result is mould in the roof space, mould reappearing on the bathroom ceiling from above, damp insulation that performs poorly, and in bad cases timber decay.

Checking it is easy. Look in the roof space with a torch and follow the duct from the fan. If it ends in a loose flexible duct pointing vaguely upward, or has no duct at all, it is discharging into the cavity. Proper installation ducts the fan to an external outlet through the eave, the gable or the roof, with the duct properly connected and sealed at both ends and no sags where condensate can pool.

Beyond ducting, three things make an extraction system work. Adequate capacity for the room size, a run time long enough to clear the moisture after the shower rather than stopping with the light switch, and a way for replacement air to enter the room, since a fan cannot extract from a sealed space. A timer or humidity sensing switch handles the second and leaving the door ajar handles the third. Roof space ventilation is the companion issue, since a poorly ventilated cavity holds whatever moisture reaches it. Roof ventilation addresses the cavity above the living areas.

What Fixing the Ventilation Actually Involves

Ventilation is where the real money should go on a recurring mould problem, and it is usually cheaper than owners expect once they know what the options are. The single most common fault in South Australian homes is an exhaust fan discharging into the roof space rather than outside. It moves the moisture out of the bathroom and deposits it above the ceiling, where it condenses on the underside of the roof and eventually shows up as ceiling mould in the next room. Ducting it properly to an eave or roof vent, covered at exhaust system repair, costs $350 to $900 and fixes the cause rather than the symptom.

Fan capacity matters as much as ducting. A builder grade fan rated for a small ensuite will not clear a family bathroom, and running an undersized fan for longer does not compensate. Look for a fan sized to the room volume and, ideally, one on a timer or humidity sensor so it keeps running after the shower stops. Rangehoods deserve the same check. Many are recirculating rather than ducted, which filters grease but returns all the moisture to the kitchen, and that moisture ends up on the coldest wall in the house rather than outside it.

Passive ventilation helps but is limited in a cold snap, since nobody opens windows in July. Trickle vents, wall vents and subfloor ventilation all contribute, and improving airflow under a suspended timber floor addresses damp rising into the rooms above. Evaporative cooling is the South Australian complication worth naming. It works by adding moisture to the air, and it needs windows or doors open to exhaust that air. Run with the house closed up, it raises indoor humidity sizeable and contributes to a problem that then appears months later in winter.

Treating Growth Before Painting

Existing mould has to be killed and removed rather than covered, and the method matters more than people assume. Wiping visible mould off a surface removes the appearance and leaves the structure behind. On a porous surface such as plasterboard or unsealed plaster, growth extends into the material and a surface wipe achieves very little. Household bleach is the common instinct and it has a specific weakness. It is effective on hard non porous surfaces such as tiles and glass, and on porous surfaces the water carries deeper than the active ingredient does, so it bleaches the visible growth pale while leaving material behind that regrows. A surface that looks clean and darkens again in a few weeks is usually this.

Suitable commercial treatments and correctly diluted products designed for the purpose penetrate better, and the important step in all cases is removing the dead material rather than leaving it on the surface. Where growth is extensive, has been present a long time, or extends into the substrate, replacement is more reliable than treatment. Mouldy plasterboard in a bathroom ceiling is usually cheaper to cut out and replace than to attempt to save. Ventilate while working, wear suitable respiratory protection and gloves, and keep people with respiratory conditions out of the area. Mould removal specialists handle larger jobs, and workplace requirements are administered by SafeWork SA.

Dealing With Growth That Is Already There

Coating over existing mould is the most common mistake on this job, and it fails reliably. The growth continues under the film, the coating loses adhesion and the stain bleeds back through within months, so the surface has to be dealt with before anything is applied. Household bleach is the default response and it underperforms on porous surfaces. It bleaches the colour out of the growth so the stain disappears, which looks like success, while the hyphae remain in the substrate and regrow. On a non-porous tile or glass surface it works fine, and on plasterboard or render it does not.

Proper treatment kills the growth and physically removes it rather than lightening it. Professional treatment runs $200 to $800 a room depending on the extent, and the removal step matters as much as the killing step because dead spores still cause staining and can still affect people who react to them. Some surfaces cannot be recovered. Plasterboard that has been wet repeatedly and has mould growing through the paper rather than on it needs replacing rather than treating, which sits at gyprock repair, at $600 to $1,500 for a ceiling, and treating it is money spent twice.

Drying is the step people skip because it is invisible and slow. A surface that has been cleaned still holds moisture, and coating it before it has dried out traps that moisture under the film. Allow days rather than hours, and longer on solid masonry in winter. Anyone with asthma, allergies or reduced immunity should not be doing this work themselves, and that is worth saying plainly. Disturbing mould releases spores, and a contractor with containment and the right protective equipment is the sensible answer in an occupied home.

What to Specify

The products are readily available and choosing well is straightforward once you know what to ask for. Major manufacturers including Dulux, Taubmans, Haymes, Wattyl and Resene all produce interior ranges formulated for wet areas with mould inhibiting additives, and Zinsser produces a well known mould resistant primer and finish system used where problems are persistent. Any of them will do the job on a properly prepared surface. Ask the painter which product they intend to use and check it is rated for wet areas rather than general interior use.

Sheen level matters more than brand. A satin or semi gloss finish in a bathroom, laundry or kitchen resists moisture and wipes clean far better than a flat or low sheen, and the ability to wipe a surface down is itself part of controlling mould. Ask the contractor to name the product rather than describing it, because a named product can be checked against the manufacturer's data sheet for what it is designed to do, how it should be applied and what preparation it requires. A quote saying mould resistant paint gives you nothing to check.

Where staining has occurred, a stain blocking primer is needed under the finish. Mould leaves marks that pass through waterborne paint and reappear weeks later, and the same applies to any water staining from the underlying leak. One honest caution on marketing. Some products are promoted with claims about killing mould or preventing it permanently. The additives inhibit growth on the film and they deplete over time, and no coating removes the need to control moisture. Treat strong claims accordingly.

Choosing the Right Coating and Sheen

Once the moisture problem is genuinely resolved, the coating decision is fairly simple, though a few details make a real difference to how long the result lasts. Mould resistant coatings carry biocides that inhibit growth on the paint film itself, and the good ones hold that property for years rather than months. Product quality varies considerably at this end of the market, and the gap between a budget and a premium bathroom paint is small in dollars and large in service life. Ask which product is quoted rather than accepting a general description.

Sheen level matters as much as the additive. Flat paint is porous and holds moisture at the surface, which is exactly what you do not want in a wet room, while a low sheen or satin finish sheds water and wipes clean without showing every mark. Full gloss is more resistant again but shows every imperfection in the wall behind it, which is why low sheen is the usual compromise in a bathroom or laundry. Ceilings are where the specification most often falls short. Bathroom ceilings get the worst of the condensation and are frequently painted in the same flat ceiling white used through the rest of the house, which has no mould resistance and holds moisture readily. Specifying a proper wet area ceiling product costs very little more and addresses the surface that fails first.

Colour is worth a thought as well. Very dark colours in a bathroom show every water spot and mineral deposit from Adelaide's hard water, while mid tones hide both. That is a practical consideration rather than an aesthetic one, and it affects how often the room needs wiping down. Finally, ask what the warranty covers and what voids it. Most manufacturers will stand behind the mould resistance of the film where the surface was prepared correctly and the moisture source was addressed, and most will decline where it was not. That distinction is why this page puts the coating last rather than first.

Where Mould Appears

Location tells you a great deal about cause, which is why a contractor should look at the whole room rather than only the affected patch. Bathroom ceilings and the wall above a shower point to extraction, since that is where shower moisture goes and condenses. Room corners on external walls, behind wardrobes and behind furniture pushed against external walls point to condensation on cold surfaces with poor air circulation. So do window reveals and the wall behind curtains.

A defined patch with staining, particularly on a ceiling, points to a leak from above, whether roof, plumbing or a bathroom on the floor over it. A band above floor level accompanied by damaged plaster or paint blistering points to rising or salt damp in the masonry rather than to indoor humidity. Mould behind wallpaper on an external wall is common in older homes and it is usually condensation, with the paper both hiding it and providing a surface it grows on happily. Wallpaper removal frequently reveals it.

Inside a wardrobe on an external wall is worth naming separately because it is so common in Adelaide and so easily improved. Air does not move in a closed wardrobe, clothing holds moisture, and the wall behind is the coldest surface in the room. Leaving the door ajar and pulling the contents a few centimetres off the back wall makes a measurable difference at no cost. Pulling wardrobes a few centimetres off the wall to allow air movement behind them costs nothing and helps considerably.

Health Considerations

Mould in a home is a health matter as well as a maintenance one, and it is worth stating plainly without overstating it. Exposure to mould indoors can cause or worsen respiratory symptoms, and people with asthma, allergies, existing respiratory conditions or reduced immunity are more affected than the general population. Infants, older people and anyone undergoing treatment that affects immunity sit in that more susceptible group. Symptoms commonly reported include irritated eyes, nose and throat, coughing, wheezing and worsening of existing asthma.

This is not something to diagnose from a webpage. If anyone in the household has persistent symptoms that seem connected to conditions at home, that is a conversation for a doctor, who can assess the individual properly. Practical guidance on mould in homes is published by SA Health, and it is a sensible starting point for anyone dealing with a persistent problem. From a practical standpoint the message is the same either way. Extensive or persistent mould signals a moisture problem that should be identified and fixed rather than managed cosmetically, and the sooner that happens the smaller the job.

Rentals and Responsibility

Mould is one of the more common sources of dispute between South Australian tenants and landlords, and the principles are reasonably clear even though individual cases vary. Residential tenancies in this state are governed by legislation administered by Consumer and Business Services, with disputes heard by the South Australian Civil and Administrative Tribunal. In general terms, mould arising from a defect in the property is the landlord's responsibility to rectify. A leaking roof, a failed shower membrane, rising damp, a bathroom with no exhaust fan or one that discharges into the roof space are all building issues.

Mould arising from how the property is used may be the tenant's responsibility. Never using the exhaust fan, drying washing indoors without ventilation, or blocking vents fall into that category. In practice many cases involve both, and the productive approach is documentation rather than argument. Tenants should report mould in writing as soon as it appears, with dated photographs, and keep a record of what was reported and when. Landlords and agents benefit from responding promptly, since mould worsens and the repair cost grows.

Information on tenancy rights and obligations is published by Consumer and Business Services, and the dispute pathway by SACAT. For landlords, the vacancy between tenants is the cheapest and easiest time to deal with both the cause and the coating. Disputes that cannot be resolved between the parties are heard by the state tribunal. Keeping the written record from the outset is what makes either path workable.

Mould in Rented Homes

Mould in a rental is one of the more contested maintenance issues in South Australia, largely because the cause is often shared between the building and how it is being used. The building side covers structural defects, leaks, inadequate or absent ventilation and anything that lets water in, and those sit with the landlord as repairs. The occupancy side covers drying washing indoors, running an evaporative cooler with the house shut, never opening a window and not using the exhaust fan, and those sit with the renter. Most real cases involve some of both, which is why they escalate more often than a burst pipe would.

Reporting matters more than arguing about cause. Put it in writing with photographs and a date, describe where the growth is and how long it has been there, and say what you have already tried. A written record dated early is worth a great deal if the matter ends up before the tribunal, and it also tends to get a faster response than a phone call. Repeating the report if nothing happens is worth doing rather than assuming the first one was received.

Landlords are generally better off treating a ventilation complaint seriously and early. A properly ducted exhaust fan at $350 to $900 is cheaper than repeated repainting, far cheaper than replacing a mouldy plasterboard ceiling, and cheaper again than a vacancy while the problem is sorted out. It also removes the argument, because a home with working ventilation puts the responsibility squarely back on how the property is being used. Investment properties are where these problems compound quietly. Nobody who notices the early signs has any incentive to report them if they expect to be blamed, so the first the owner hears is often at the end of a tenancy when the damage is well advanced. Building an annual inspection into the management arrangement catches it while it is still a cleaning job rather than a replacement one.

Where a dispute does not resolve, South Australia's tribunal handles residential tenancy matters and both parties can apply. Going in with dated photographs, written reports and any contractor assessment carries considerably more weight than a verbal account. That documentation is the practical difference between a claim that succeeds and one that becomes one person's word against another's. Both parties can apply, and the process is designed to be accessible without legal representation.

What Drives the Price

The extent of existing growth comes first, since treatment and removal are priced by area and by how far into the substrate it has gone. Substrate damage follows, because prolonged damp softens plasterboard, lifts coatings and can rot timber, and replacement is frequently cheaper than attempting to save badly affected material. The cause is the largest and most variable item, ranging from a few hundred dollars for a properly ducted fan through to several thousand for damp remediation or insulation work. The coating premium itself is modest at roughly twenty to forty per cent over a standard interior product, which on a bathroom is a small share of the total. Access and preparation behave as they do in any interior job, with wet areas adding the fiddle of working around tiling, tapware, screens and fittings. Drying time costs nothing and delays the program, and a contractor who allows for it is doing the job properly rather than padding the schedule.

Mould Coating Costs Across Adelaide

Adelaide pricing tracks the extent of the problem far more than the suburb, though housing age changes the odds on what you will find. Older solid masonry stock through the inner and northern suburbs carries the problem far more than newer cavity brick. Ask the contractor what they see most often in your area, since local experience is genuinely useful here. Ask the contractor what they see most in your part of the state.

The third row is the one to notice. A properly ducted exhaust fan costs less than treating and repainting a bathroom twice, and it is the item most likely to stop the problem returning. Spending there before spending on paint is the recommendation this whole page builds toward. It is the one line in the table that changes the outcome rather than the appearance.

Regional South Australia

Regional pricing carries travel, and more importantly the climate varies enough across this state to change how common the problem is. The Hills and the South East run colder and wetter than the Adelaide plains, while the Riverland and the upper north are drier and see far less of this. Where you are affects how often the problem recurs as much as what it costs to fix. Local experience matters more here than on most trades.

Mount Gambier and the Limestone Coast see meaningfully more of this than the plains, with the highest rainfall in the state, cooler temperatures and longer damp periods. Houses there benefit from better extraction and heating rather than better paint. The Adelaide Hills share the pattern for different reasons, with heavy tree cover, shaded blocks and cooler air producing surfaces that stay cold and damp longer. Holiday properties across the Fleurieu, Yorke Peninsula and Kangaroo Island have a specific version of the problem, since a house shut up for weeks with no air movement and no heating develops mould readily. Leaving internal doors open, wardrobe doors ajar and arranging occasional ventilation makes a sizeable difference. Inland districts are drier and see less of it overall, with evaporative cooling and closed up houses being the main local contributor rather than winter condensation.

What to Look Out For

Treat any quote that offers a mould resistant coating without discussing the cause as incomplete. Ask the contractor directly what they think is producing the moisture. Check where your exhaust fan discharges before you spend money on anything else. A fan venting into the roof space is the most common and most fixable fault in South Australian homes and it costs a few hundred dollars to correct.

Refuse to have live mould painted over. Growth must be killed and removed first, and a contractor willing to coat straight over it is selling you a few months. Be sceptical of products promoted as permanently preventing mould. Recoating on the manufacturer's interval is what keeps that protection working.

Look at the pattern of where the mould is, because corners and wardrobes on external walls mean condensation, a defined stained patch means a leak, and a band above floor level means damp in the masonry. Each has a different fix. Allow drying time between treatment and coating, and be suspicious of a contractor offering to do both in one visit on a surface that has been wet. Finally, check the licence and insurance. Painting is building work in South Australia and requires a building work contractor's licence with no dollar threshold, and consumer guarantees are administered by the ACCC.

What to Look for in a Quote in SA

A quote worth comparing addresses the cause, the treatment and the coating as three separate things. Specifically: what the contractor believes is causing the moisture and what they recommend about it, the areas to be treated and the treatment method, whether affected material is being treated or replaced and on what basis, the drying period allowed before coating, any stain blocking primer, the named finish product and its sheen, the number of coats, protection of fittings and tiling, and whether ventilation work is included or quoted separately. When you enquire, describe where the mould is and its pattern, say whether there is an exhaust fan and whether you know where it vents, mention the age of the house and whether the external walls are insulated if you know, note any history of leaks or damp, say whether the house runs evaporative or refrigerated cooling, and mention if anyone in the household has respiratory sensitivities. Photographs of each affected area help considerably.

Get three quotes and compare what each says about the cause rather than only the price. A contractor who identifies a fan discharging into the roof space has given you more value than one offering a cheaper repaint. Keep a record of what was found, what was fixed and which products were used. Mould problems recur when conditions change, and knowing what was done last time makes the next conversation much shorter. You will also find mould and damp treatment and smaller painting contractors here for work at either end of the scale.