After storm or flood water gets into a house, work in this order: make it safe, stop more water coming in, get standing water and soaked materials out, and start drying, photographing everything before you move or throw it out. Speed matters because damp materials that are not fully dried grow mould, and the longer they stay wet the more likely the job becomes a remediation rather than a dry-out.
1. Make it safe
- Keep away from water near power points, switches or the switchboard. Only isolate power if you can reach the switchboard from dry ground; otherwise wait for an electrician. NSW Health’s advice on staying healthy during and after floods says electrical equipment and hot water systems exposed to floodwater should be inspected by a licensed electrician before use, and never to run a generator indoors.
- Treat water from outside, off the road or out of drains as contaminated. Keep children and pets away, and wear boots, gloves and eye protection when cleaning up.
- Stay out of rooms where a ceiling is sagging or bulging with water.
- In older homes, be mindful that some building materials may contain asbestos; NSW Health’s household clean-up advice says to take appropriate precautions. Asbestos must be removed by a licensed asbestos removalist.
- For storm damage that needs emergency help, such as a damaged roof or fallen tree, contact the NSW State Emergency Service.
2. Stop the water
A house cannot dry while water is still arriving. For a burst pipe, flexi hose or hot water system, turn the water off at the meter and call a licensed plumber. For roof or storm damage, a temporary tarp only if it can be done safely, then a roofer for the repair. Overflowing gutters and downpipes that dump water against the house are a common Illawarra cause; rising damp vs condensation covers drainage faults that keep feeding a wall after the rain stops.
3. Photograph and notify your insurer
Before removing anything, take dated photos of every affected room, the water source if visible, and the items you throw out. Contact your insurer early, even before you know the full extent, and ask what they need and whether they want to send an assessor before more is removed. Cover depends on your policy: mould following a sudden insured event such as a storm or burst pipe is treated differently from gradual damp, and flood and storm definitions vary between policies. The mould and home insurance guide explains the general principles; this is general information, not insurance or legal advice.
4. Get water and wet materials out
- Remove standing water with buckets, a wet vacuum or towels for small amounts; larger volumes, especially over carpet, need extraction equipment.
- Lift furniture, rugs and boxes off wet floors onto blocks or into a dry room.
- Saturated carpet underlay, soaked insulation and porous items that cannot be thoroughly cleaned and dried are usually better removed than left to keep the room damp. NSW Health notes flood-affected mattresses are hard to treat and may need to be discarded.
- Floodwater-affected hard surfaces should be cleaned and disinfected, as NSW Health’s clean-up page sets out.
5. Dry it properly
Open doors and windows on dry days and run fans; NSW Health also suggests draining water away from under the house to increase airflow and checking for water or mud trapped in wall and floor cavities. That last point is where DIY drying usually falls short. Surfaces can look and feel dry while the wall cavity, the underside of flooring or the subfloor is still wet, and that hidden moisture is what grows mould weeks later. See hidden mould behind walls for the signs, and subfloor ventilation if water got under a timber floor.
DIY drying or professional water damage response?
Three things decide it: what the water was, how long materials stayed wet, and how far it travelled.
| Situation | Reasonable approach |
|---|---|
| Clean water from a supply pipe, caught quickly, one room, nothing in cavities | Airflow, fans and a dehumidifier, then check with a moisture meter |
| Stormwater, floodwater, drain or sewage water | Professional response; contaminated porous materials generally have to come out |
| Wet carpet across several rooms, or water under flooring or into walls | Professional extraction, structural drying and moisture logging |
| Musty smell or visible mould already appearing | Inspection of cavities and subfloor, then drying plus remediation |
| Rental property, or insurer wants a make-safe or drying report | Professional response for a documented record |
A water damage and mould response involves mapping the wet area with moisture meters, extracting water, removing what cannot be dried, running drying equipment until readings return to normal (not to a fixed schedule), treating at-risk surfaces, and providing the moisture logs and photos an insurer will want.
Where in the Illawarra this hits hardest
East coast lows and big summer storms can push water into homes that cope fine in normal weather: wind-driven rain past window and door seals, overflowing gutters, and stormwater pooling against slabs or running under raised floors.
- Low-lying ground near Lake Illawarra and its creeks. Parts of Warilla, Barrack Heights and Oak Flats around the lake, and flat land around Dapto threaded by Mullet Creek, can take stormwater into yards and sometimes homes. The ground often stays wet after the rain stops, so drying takes longer.
- Newer, well-sealed homes. In estates such as Shell Cove, Flinders and Calderwood, water damage is more often plumbing related (a burst flexi hose or failed hot water unit). A tightly built house has fewer natural airflow paths, so water trapped under carpet or in cavities needs deliberate drying. The Shellharbour location page has more on the area’s housing mix.
- Older fibro, weatherboard and brick homes tend to hold moisture in timber floors and subfloors once wet.
Frequently asked questions
How soon after a storm does mould start growing?
There is no fixed clock; it depends on the material, temperature and how wet it is. The safe assumption, consistent with NSW Health’s advice that mould may develop if items are not completely dried, is that anything left damp is at risk, so start drying straight away.
Is it too late if the house has already been wet for several days?
Not too late, but the job has probably changed. Materials that sat wet are more likely to need mould treatment as well as drying, and checking cavities and subfloors becomes more important.
Is stormwater treated differently from a clean pipe leak?
Yes. Water that has picked up ground runoff or been in contact with drains or sewage is a higher-risk category than a clean supply-line leak, which changes what can be dried in place and what has to be removed.
What if I can smell damp but cannot see mould after a storm?
That usually means moisture or growth somewhere hidden: under flooring, inside a wall cavity or in the subfloor. A moisture survey is the next step rather than more waiting.
Will insurance pay for storm-related mould?
Often when the mould follows a sudden insured event, though gradual damp and condensation are typically excluded. Check your policy wording and notify your insurer early, before you remove or replace anything.