Hard Water and What It Does to Your Home

If you see white crust on faucets, spots on dishes, or soap that won't lather, you probably have hard water. It isn't a health hazard for most people, but over time it can take a toll on plumbing, water heaters, and appliances. Here is what hard water does and how to manage it.

What hard water is

Hard water contains higher levels of dissolved minerals, mainly calcium and magnesium. Water picks up these minerals as it moves through rock and soil. Hardness varies widely across the US and even between neighboring towns.

You can check your water's hardness with a home test kit, by asking your water utility for its water quality report, or by having a water treatment company test it.

Signs of hard water

• White or chalky buildup on faucets and showerheads
• Spots and film on dishes and glassware
• Soap scum in tubs and showers
• Stiff laundry or clothes that look dingy
• Low water pressure from clogged aerators and showerheads
• Dry skin or hair after showering

How hard water affects your home

Water heaters

When water is heated, minerals settle out and form scale. In tank water heaters, sediment collects on the bottom. This can cause rumbling or popping noises, reduce efficiency, and shorten the heater's life. Tankless water heaters can develop scale inside the heat exchanger. See our water heater coverage page for how plans treat these units.

Plumbing

Scale can build up inside pipes, fixtures, and valves over time, reducing flow and causing parts like faucet cartridges and toilet fill valves to wear out sooner.

Dishwashers and washing machines

Mineral deposits can clog spray arms, valves, and heating elements in dishwashers. In washing machines, scale can affect inlet valves and heating parts on models that heat water. Our dishwasher coverage page explains what plans commonly include.

Other appliances

Refrigerators with ice makers and water dispensers, coffee makers, and humidifiers can all be affected.

Ways to manage hard water

1. Flush your water heater. Draining some water from a tank heater periodically helps remove sediment. Tankless units often need descaling. Follow the manufacturer's instructions.
2. Clean aerators and showerheads. Soak them in white vinegar to dissolve buildup.
3. Use appropriate detergents and rinse aids. Products made for hard water can help with spots and film.
4. Consider a water softener. Softeners replace hardness minerals, usually through ion exchange. They need salt refills and occasional maintenance.
5. Look at other treatment options. Some systems reduce scale without removing minerals. Results vary, so research carefully and ask for testing data.
6. Check filters on refrigerators and other appliances and replace them on schedule.

If you install a softener, follow the installer's guidance and local plumbing codes. Some people prefer not to drink softened water or to use it for plants, so many homes leave one kitchen tap or outdoor spigots on unsoftened water. A plumber can help you plan this.

Signs hard water is already causing damage

• A tank water heater that rumbles or pops as it heats
• Hot water that runs out sooner than it used to
• Dishwashers that leave a gritty film even with fresh detergent
• Faucets and toilets that drip or run after valves wear
• Low flow at several fixtures at once

Catching these early gives you a chance to clean, flush, or repair parts before they fail completely.

Hard water and home warranties

This is an important detail. Many home warranty contracts exclude damage caused by sediment, mineral buildup, or scale. That means if a water heater fails mainly because of sediment, or a dishwasher valve clogs with minerals, a claim may be denied or limited.

Some plans handle this differently, and some offer coverage for failures where mineral buildup is one factor but not the only cause. Read the exclusions section carefully, and look for words like "sediment," "scale," "mineral deposits," and "water quality."

Regular maintenance, like flushing your water heater and keeping records, can help you prevent failures and show that you cared for the equipment. Our plumbing coverage page covers related terms.

How Warranty Wizards can help

We help you compare home warranty plans from independent third-party providers and spot exclusions like sediment and mineral buildup before you buy. We'll explain what a plan covers in plain language. Request a free quote at /get-a-quote/.