What Causes High Humidity in a House

High humidity in a house happens if moisture enters the house and cannot get out. Main causes are leaks, everyday activities like showering and cooking, rising damp, AC or your dehumidifier not working properly.

A Dry Room Without High Humidity
This is how a house interior should look like

Aside from your AC unit not completely eliminating humidity from the air that circulates inside your house, the following are the three most common ways to generate too much moisture inside your house and causes of high humidity:

  • Leaks – Moisture can enter your home through cracks and leaks around or in your house. To locate the culprit for these kinds of problems, search for a cracked roof tile, loose zinc fitting or joint, or leaky pipes.
  • Everyday activities – You might be surprised to know that most of your day to day activities may actually introduce excess moisture in your home. Daily activities such as washing the dishes, cooking, taking a shower, running the washing machine, sweating and breathing can all cause moisture buildup in your house, particularly when you have a big family.
  • Rising damp – It is very rare for rising damp to happen but this is a more serious culprit for high humidity inside a house. Rising damp happens when ground moisture rises through pores in masonry and bricks. Watch out for signs of rising damp like rotting window frames, mold, wet or damp patches on walls, and flaky plaster. If there is a reason for you to suspect rising damp in your house, it is definitely time to hire professionals to help you out.

Once the temperatures start to climb, you may notice several changes around your house.

Perhaps you noticed fogs forming on your windows or you caught a whiff of musty air. Or, probably you are relaxing in your kitchen with a glass of juice and all of a sudden, you start sweating even if you are not exerting physical energy aside from lifting the glass.

You might also notice damp spots on the walls and what seems like mold in the shower.

If any of these sound familiar, your house may have an issue with excessive humidity since your AC unit can no longer control the moisture level in the indoor air.

This will not just make you feel uncomfortable and hot for, at the same time, high indoor humidity can lead to more serious concerns such as rust, mildew, and mold, not to mention that it can also pose possible health risks.

In areas with humid and hot climates, homeowners usually contact AC repair companies because of overly humid homes each year once the season gets warmer.

If you want to put an end to the heavy and sticky feeling inside your home for good, it is important to make yourself more familiar about high humidity and what risks are associated with it.

Free Chart - High Humidity Issues/Problems
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A Short Overview of High Humidity

How many times have you heard someone say that it is not the heat but the humidity instead? This is more often heard in areas that are wetter and hotter. Maybe you have even used this phrase yourself.

But, did you ever ask yourself what humidity really is?

In the most basic terms, humidity refers to the measurement of the amount of water vapor present in the air. Once the air retains more amount of water vapor, the environment is going to feel more humid. If the air retains less amount of water, the environment is going to feel dry.

In general, people are more comfortable when the humidity level is low to medium amount. Too low humidity may feel uncomfortable and can be detrimental to your house.

On the other hand, excessive humidity is not something that most people will prefer as this can also cause both home and health complications.

You will generally want your house to have a humidity level of somewhere around 30% and 50%.

Health Problems of High Humidity in a House

When humidity increases beyond 60%, you will notice that you feel uncomfortable and clammy. However, feeling overheated is not just the sole issue with high humidity.

This is because there are still a lot of other health consequences of humidity, with some being a bit serious.

Below are some of the top health concerns that result from high humidity in a house:

1. Dehydration

Once the humidity in your environment rises, it can become more and more difficult for your body to keep you cool.

During humid weather, sweat cannot evaporate really well so your body pumps out even more amounts of sweat to try to compensate.

Too much sweating can then lead to loss of essential minerals and water that your body requires to function properly.

Your body will also start to use some other forms of defense mechanisms to help protect you from overheating such as altered blood flow and increased respiration.

These can all put you at risk of respiratory issues, dehydration, muscle cramps, fatigue, and more.

2. Sleep issues

High humidity has been associated with sleep problems.

Once humidity gets too high to the point that you feel overheated, you will toss and turn throughout the night. This can then lead to a less restful sleep.

Humidity increases congestion as well that can disrupt your breathing and cause snoring.

3. Allergies

Moisture is something that bacteria love and a damp home can lead to the growth of bacterial colonies on moist floors and walls.

Dust mites can also thrive in humid and warm environments.

Did You Know?

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High humidity can also welcome dangerous molds that can contribute to asthma attacks, allergies, and a lot of other health issues.

Things don’t just stop there, though. More than the health concerns, an excessively humid house can also have a negative effect on the structure of your home.

High amounts of moisture in your house can make the wood materials to swell, rot, and ultimately, deteriorate.

High levels of humidity can also encourage oxidation and rust.