Flood damaged goods outside a Brisbane home. Image by Glenn Walker.
Repairing flood damaged buildings
The recent flooding across Australia has damaged many homes and buildings. This page provides information about cleaning and repairing flood damaged buildings.
25 January 2011 | Updated 6 March 2014
Each year in Australia many houses and other buildings are damaged by flood. What should property owners do to return their house to its condition before the flood?
Most importantly, do not attempt to re-enter the house or undertake repairs until floodwaters have receded to a safe level and authorities permit access to the area.
Before entering any building, evaluation of safety aspects must be made by the relevant authorities. This includes:
- structural integrity
- electricity (remembering that even where power has been turned off by the authorities, solar power systems may still be active in individual homes)
- gas safety
- sewerage services.
Some building materials in older properties may contain asbestos. If unsure, expert advice should be obtained.
For insurance purposes, it is suggested to take photographs before and during the cleanup process.
Should rectification involve any building works, please ensure that the relevant regulatory requirements in your State/Territory are observed (including requirements for building permits).
The full rectification process may take months. However, to minimise repairs, it is important to start work as soon as the rain has stopped and the water receded.
Do not attempt to re-enter the house or undertake repairs until floodwaters have receded to a safe level and authorities permit access to the area.
The tasks which need to be done quickly as possible are:
- Clear up, drain and start drying out the house as soon as the flood waters recede.
- Take out everything that is wet and that can be moved – floor coverings, furniture, bedding and clothing.
- On dry days, keep all doors and windows open; on wet days, leave windows ajar.
- Drain away water under the house, and try to increase the airflow to assist drying.
- Check for trapped water and mud in wall cavities, as well as under such things as shower trays, baths, benches and bottom shelves.
Once the structure of the house has dried out completely the final two tasks can be completed:
- Replace damaged wall linings, floor coverings, etc. only after the structural timber is dry. Drying could take months.
- Leave redecorating for at least three months after finishing the repairs. If you paint or paper too soon you could risk mould, blistering and peeling.
While most of the cleaning up and repairs can be done by any able-bodied person or competent home handyman, some jobs must be done by a tradesman or other qualified person and should never be attempted by the homeowner. These include:
- provision and safety of electrical services
- any evaluation or rectification of structural integrity
- plumbing services (particularly with respect to water ingress in gas lines/appliances and septic tanks).
Because flood water is often polluted with sewage, you must:
- throw out any contaminated food
- keep children away during the cleaning up
- use disinfectant when cleaning, and always wash your hands before eating and drinking
- disinfect cuts and cover with a waterproof dressing
- bury all accumulations of faecal matter quickly.
It is recommended to seek advice before emptying in-ground swimming pools. As the groundwater table is likely to be very high, a pool may lift if emptied, causing unnecessary damage.
Do not light fires in brick fireplaces for at least two weeks, and then use only small fires until the firebricks have dried out.
Fans can speed up the drying process by increasing the air flow and thus the evaporation rate within the building. Heaters will also help drive off the moisture, but facilitating good airflow (including open windows and the use of fans) is often more beneficial than using heaters.
Remember that drying out properly can be a slow process. However, with patience and appropriate care many building elements can be returned to full service.
Everything that is wet and that can be moved – floor coverings, furniture, bedding, clothing, etc. – should be taken outside for cleaning and drying whenever the weather permits. Leave nothing that can trap moisture and prevent the structure from drying.
To remove a sheet of vinyl, lift a corner and slowly and carefully pull up the rest. The easiest way to lift vinyl tiles is to gently lever them up with a garden spade. If there is particleboard underneath, take extra care as a spade can damage this flooring material. (Please note that some vinyls may contain asbestos).
Draining, cleaning, drying and repairs
Once all the wet contents of the house are outside, cleaning up and drying out can begin.
On dry days, keep all doors and windows open. On wet days, leave windows ajar – the inside of the house will only dry if moisture can get out.
Turning on heaters while leaving the windows open will help drive off moisture. However, do not use more heaters than necessary as too much heat may warp and crack wood. Air flow (i.e. fans and open windows) is often more beneficial than the use of heaters.
Look for trapped mud in the less obvious places – under shower trays, benches, baths and bottom shelves. Remove the skirting or plinth covering these spaces and hose or pump out the mud.
Wetting for a short period does not necessarily cause permanent damage to many building materials but they should be dried out as soon as possible. In most cases, especially with masonry materials such as bricks and concrete blocks, drying can take several months.
Ignore any mould that grows on wet linings and timber until drying is complete. Once dry, it can be removed with household bleach, using several applications if necessary. However, remember that bleach can affect the colour of some materials.
The main message is BE SAFE and DON'T RUSH.
Drying out properly will take a long time but when complete, most troubles remaining will be decorative and easily repairable.