Humidity levels in your house are important factors of your overall comfort. Mold and mildew may grow in high humidity environments. A lack of humidity, on the other hand, will result in dry skin and maybe ruined furnishings.

As a result, understanding the optimal indoor humidity is critical. That way, you’ll be able to make the necessary adjustments to improve your comfort.

However, detecting indoor humidity isn’t always straightforward. It is much greater during some seasons than others, and vice versa.

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How to Gauge Indoor Humidity Levels

If you don’t have a sixth feel for humidity, you’ll need to do some testing and maybe use a tool to figure out the exact amounts. There are a few clear indicators that your indoor humidity is out of sync, of course.

Fogging or condensation on windows, as well as excessive moisture, are early signs of too much moisture. Mold growing on the walls and ceilings is a warning indication.
Low humidity: Increased experiences of static electricity are generally the first indications. In the long term, you’ll probably see dry or cracked paint and millwork.
Indoor humidity levels may be measured in two ways:

The Ice Cube Experiment

The ice cube test will not give you a precise humidity percentage, but it will give you a rough estimate.

Select a room: To test the humidity in your house, choose a room. Except for the kitchen and the bathroom, you can utilize any location. Due to their constant use of water, these places will not provide you with an exact estimate.
Place the ice cubes in the following order: Fill a regular-sized drinking glass halfway with ice cubes.
Toss in some water: Pour some water into the glass and gently mix it. You only need a small amount of water to cover the ice cubes.
Remove yourself from the room: Leave the room for three to four minutes after adding the water.
Examine your outcomes: Return to the room when the timer goes off. Humidity is high if you observe droplets on the outside of the glass. If there aren’t any, the level is too low, and a change should be considered.


The ice cube test is a good way to get a rough sense of humidity levels. A hygrometer, on the other hand, is required for precise findings.

The hygrometer will determine the amount of water vapour or humidity in the air. Fortunately, it isn’t a prohibitively expensive expenditure. For as low as $10, you can have either an analogue or digital one.

To assess the humidity in your house, use the hygrometer in several rooms. It’s possible that certain locations have a lower or higher reading than others.

The ideal indoor humidity level is between 30 and 50 percent.

What Are Optimal Humidity Levels?

Humidity levels fluctuate when the weather changes from hot to cold (3). Seasonal humidity is a term used to describe this phenomenon. It has an impact on both your comfort and your house, therefore it’s critical to control it properly.

In the winter, we often describe the air as crisp, harsh, or dry. In the summer, it’s hotter, muggier, and stickier. These are excellent explanations of humidity levels at different times of the year.


The air holds more moisture during the summer and warm months. Because more moisture is present, it takes longer for it to evaporate, raising humidity. As a result, the air may feel sticky or thick, causing us to sweat more.

In the summer, keep interior humidity levels between 30 and 45 percent. If the humidity level rises beyond 50%, it might cause pain and mould growth.

Use your air conditioner to eliminate surplus moisture to avoid a rise in humidity. You may also use exhaust fans to get rid of the heated air.

Furthermore, if you have a dehumidifier, it can assist in lowering the interior humidity. Just make sure you don’t overdo it.

Opening a humidifier on a hot summer day is a major no-no. Maintain a minimum humidity level of 30 to 50 percent, even if you have a cold or an allergy flare-up.


If you grew up in the frigid north, where the winters are long and gloomy, your skin will be familiar with the effects of low humidity. Aside from boots and coats, a thick moisturizer was a winter must-have. Winter air is harsh on exposed skin, sucking off much of the moisture and leaving a bitter, acrimonious environment behind.

It is consequently critical to restoring moisture to the indoor air throughout the winter months. Maintain a humidity level of approximately 40% indoors. If the humidity level is too high, condensation will form on the windows, signalling that the humidity level is too high and might lead to mould growth.

Bring a portable humidifier with you from room to room in the winter. Consider purchasing a whole-house humidifier if necessary.

Another great idea is to have houseplants all throughout your house. These can help to provide moisture to the air in modest amounts.

When it’s chilly outside, we always put little water basins near the heating system. Small hangable containers operate similarly to humidifiers and may be hung on radiators.

Low Indoor Humidity

Problems Associated With Low Indoor Humidity

We are more concerned with high humidity than low humidity, owing to our dread of mould and mildew. However, too little humidity may be harmful to our general health as well as our house. Let’s have a look at how it works:

Effects of Low Humidity on Health

Low humidity might be deceiving. Because it provides an environment where germs and viruses grow, it can cause a range of health issues. The following are some of the ailments:

Lips and skin that are dry.
The throat and nose are scratchy.
Colds are more likely to develop.
Respiratory problems
Nose bleeding.
Problems with the lungs and sinuses.
Body temperature is low.

Low Humidity’s Impact on the Home

Low humidity might cause problems in the home over time. These are some of them:

Static electricity levels are rising.
Wood flooring and furnishings have shrunk, separated, or warped.
It’s possible that the wallpaper will peel and loosen.
Mold has grown beneath the loose wallpaper.
Overall, the interior atmosphere has deteriorated.

How to Increase Humidity


One of the most effective methods to add humidity to your house is to use a humidifier. It’s essentially a gadget that distributes water into the surrounding environment. They come in a variety of styles and sizes.

You may require a whole-house humidifier or only a portable humidifier, depending on your needs and your household. Small humidifiers are ideal for use in the bedroom or in the corner of the living room at night. Consider a big humidifier if your rooms are vast and open.

Air Dry Clothes

Air-drying cleaned garments is one technique to replenish moisture in the air. When possible, use a drying rack instead of putting your clothing in the dryer. This also saves electricity, which is good for both your wallet and the environment.

Consider an interior vent system for your dryer if you don’t have time to wait for your clothing to dry – who does? This will allow your dryer to vent within rather than outside, perhaps improving humidity levels.

Water On The Radiator

A simple but efficient method of restoring humidity is to place a basin of water on the register. Fill a metal or ceramic dish halfway with water and set it on the floor register. The water begins to evaporate as the register heats it, releasing moisture into the air.

Try a hanging water basin if you have a radiator. Replace the water once a week, or when it has completely evaporated.

Leave Bathroom Door Open

During hot showers or baths, if feasible, keep the bathroom door open. The vapour from the water will leak through the door and mix in with the surrounding environment.

Allow the water to cool before draining it, as a courtesy to our bath-mates. The temperature of the water increases, causing the humidity to rise a little.

If you have little children, never leave a bathtub full of water alone. Children are swift and can easily fall into the water, which might have disastrous consequences.

Cook On The Stove

It’s as simple as preparing an additional meal a day to increase humidity at home. Stovetop cooking, for the most part, releases moisture into the air. It doesn’t need to be a five-star supper; just boiling spaghetti or potatoes would suffice.

Indoor Plants

Plants continually release moisture as vapour from their leaves. This is referred to as the transpiration process. It will continue to happen as long as you continue to water them as needed.

High Indoor Humidity

Issues Associated With Excessive Humidity
High humidity is typical in the summer, but it may happen at any time of year, for example, if you use a humidifier too much. It’s critical to keep an eye out for this since it can do serious harm to your property.

Health Consequences of High Humidity

Although excessive humidity has obvious health consequences, its impact on the house can also cause problems:

Sweating excessively, overheating, and heat stroke are all symptoms of heat stroke.
Asthma and allergy flare-ups are becoming more common.

Effects of High Humidity in the Home
The increasing humidity will have a direct influence on your property. This includes the following:

Condensation on the glass is excessive.
Ceilings and walls with wet patches and stains.
Mold may grow in high-moisture environments, such as the bathroom.
There are musty odours.
Mildew development.
The structure of the house may deteriorate.
Pests have a higher probability of appearing.

How to Lower Humidity


Dehumidifiers are the polar opposite of humidifiers in that they remove moisture rather than replenishing it.

If you’re concerned about moisture, a portable dehumidifier is an excellent investment because it can be placed wherever it’s required.

If high humidity is a persistent problem, a whole-house dehumidifier may be worth considering for individuals with a greater budget.

Exhaust Fans

Exhaust fans are typically found in the kitchen and bathroom, where they are used to remove smells and humidity. When you’re cooking or taking a shower, try to turn on the fan.

Take Cold Shower

Most of us don’t like to hear that we have to take a cold shower. Yes, we will leave them to the Vikings in the winter.

Even yet, if the steam and humidity remaining in the air after a hot shower is not adequately ventilated, it might cause problems. This is why, when bathing, it’s a good idea to turn down the heat as much as possible.

Use A/C

Air conditioners work wonders when it comes to reducing interior humidity. They filter the moisture within by drawing air in from the outside. Ensure, however, that the filters are clean; otherwise, the filtering process will be hampered.

Don’t Boil Water

When preparing pasta or potatoes on days when the interior humidity is higher than normal, avoid boiling water. Condensation of water may dramatically raise humidity levels. If you must, ensure sure the vapour is adequately vented.


Use a polyethylene ground cover to encapsulate your crawl space if it has an exposed dirt floor. Check to see if the earth is dry and if there is any standing water. If there is any moisture, use a fan to dry it out.

Take a check at your dryer next. Make sure the vents are directed outside rather than within since this can result in excessive dampness.

Bottom Line What Is the Ideal Indoor Humidity

Indoor humidity levels should be between 30 and 50 percent. Because this varies from summer to winter, checking with a hygrometer or other instruments is necessary.

Indoor humidity levels that are too high or too low might have negative consequences. Mold and mildew thrive in high moisture environments, while bacteria and viruses thrive in low moisture environments. Both have the potential to make us sick.

Running a humidifier when needed, cooking more, and air-drying laundry are the best strategies to counteract low humidity. Run a dehumidifier and let away vapours from cooking and showering to minimise excessive humidity.

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