One of the most important tips I can give in preventing large scale water damage in your home is to know where your Water Shutoff Valve is located in your home. This way when you see the water you can quickly shut it off. I have seen too many large water damage losses that could have been small water damage losses if the homeowner only would have known where their main water shutoff valve was located and could have quickly accessed it and shut it off. My suggestion is to know where shutoff valves for the main water supply, water softeners, ice-maker lines, sinks, and toilets are located in your home. In the event of a leak, this will help you to quickly shut off the spraying water before calling a plumber. Consider shutting off your water supply if you will be away from home for a week or more.
Regular/ seasonal inspections of your plumbing water lines and waste lines for leaks, damage, or corrosion is another really good idea. If you notice problems, hire a licensed plumber for further inspection and repairs.
Keep checks on large appliances like water heaters etc... The average lifespan of a water heater is 7-10 years. If you notice puddles around your water heater, it should be replaced. Hire a licensed plumber to inspect and flush your water heater annually.
Washing machines, dishwashers, icemakers, air conditioners and garbage disposals all use water to operate. Inspect these appliances for leaks, and periodically replace the supply hoses. Again, it is always a good idea to shut off the water supply to the washing machine before leaving your home for an extended period of time.
Keep humidity levels down as much as possible. Use exhaust fans or open windows when cooking or running the dishwasher. If your basement is prone to leaks or flooding, a sump pump is the best defense. You should keep it well maintained and tested regularly. Most sump pumps last about 10 years. Follow the manufacturer’s suggestions for testing and optimal operation. The areas around the pump should be clear of debris. Keep in mind that a battery backup is always a good idea to ensure proper operation during power outages.
During the hot months of summer, keep an eye on your air conditioners drip pan and keep it clean. When it is running a lot during hot months, the condensation builds up and drains almost continuously which creates opportunity for water damage if lines aren't draining properly. Drain the lines and ensure that they are always unobstructed and flowing properly.
If you have a basement, periodically inspect your foundation walls and floors for cracks that might allow water seepage, especially if you live in an older home or an area with poor soil drainage. If you are storing any valuables in your basement, it is always a good idea to place them in plastic containers or up on crates. You can also use storage racks or shelves to elevate items several inches above the floor.