high humidity

Understanding High Humidity and How You Can Control It

Have you observed an increase in condensation and moisture in your living space? Are you dealing with mould or mildew in various spots? It's crucial to identify the root cause of high humidity in your home and take immediate steps to manage it, as it can lead to significant damage to your health and property.  This article will explore high humidity, its causes, effects, and, most importantly, how to control it. Let's get right in.

What Exactly is High Humidity?

In basic terms, high humidity refers to when the relative humidity (RH) levels are above 60%. This relative humidity (RH) is the measure of the water vapour in the air equated to the maximum amount it can hold at a given temperature. Despite the different recommendations on the ideal humidity level in your home, it is best to ensure your property stays between 30-60%. If the RH levels in your home exceed 70%, you have a serious issue that can lead to more pronounced health and structural problems. Besides, you can use a hygrometer to measure the humidity levels in different rooms in your home.

What Causes High Humidity

Various factors contribute to high humidity in your home, one of the biggest being poor circulation. If the air in your home does not circulate as it is meant to, this can increase the humidity. So, cooking, washing, bathing, using gas heaters, and drying your clothes indoors contribute to high humidity in your home.  Other sources that contribute to the high humidity and moisture include:
  • Plumbing leaks
  • Preserved construction moisture
  • Damp ground conditions under hanging timber floors
  • Building cracks
  • Lack of air conditioning

Why is High Humidity an Issue?

High humidity increases the buildup of condensation and moisture in your home, leading to more serious issues like mould and wood rot. It can also affect the air quality and cause health problems. Hence, you need to control it. Let's discuss some of the issues with high humidity in more detail.
  • Mould and Mildew Growth
High humidity increases moisture buildup, which in turn facilitates mould and mildew growth. While mildew grows on damp surfaces, like tiles, curtains, and windowsills, mould can penetrate the building materials in walls or ceilings, making it harder to get rid of. If you cannot control the high humidity on your property, mould growth can escalate and destroy your belongings and the furnishings of your property.
  • Health Risks
High humidity facilitates mould growth, which can cause health problems like allergic reactions and respiratory issues, especially in immune-compromised people. The high condensation also aids in the growth of dust mites, which can affect people with asthma.  High humidity, which makes the air feel warmer, can cause your body to overheat, leading to discomfort and other health risks like heat exhaustion or stroke. Additionally, when your sleep environment is too moist and uncomfortable, it can be difficult for you to fall or stay asleep, leading to irritability, fatigue, and other health issues over time.
  • Rot Buildup
High humidity doesn't just threaten your health, it can also wreak havoc on your property. Excess moisture can cause timber furniture and furnishings to rot, starting with unsightly moisture stains and progressing to complete decay. This deterioration can compromise the structural integrity of your home. In the case of dry rot, a mere 20% humidity is enough to germinate the timbers, leading to severe, widespread damage.
  • Damaged Building Structure and Aesthetics
High humidity affects the aesthetics and overall structure of your home. For example, high humidity can cause condensation to gather on the walls, resulting in peeling wallpaper or flaking paint. Mould growth also results in odours, especially if your home is poorly ventilated. Besides, condensation buildup on the walls, ceilings, and windows can damage the building materials, risking the structural integrity.
  • Damage to Belongings
Mould and mildew, enhanced by high moisture, can grow on personal belongings like beds, books, clothing, and even electronics, affecting their functionalities. High humidity can also cause moisture inside the walls and electronic components, leading to malfunctions and short circuits.

How to Control High Humidity

Now that you understand the extensive impact of high humidity on your home, it's crucial to know how to control it. By taking these steps, you can ensure a comfortable and safe living environment. 
  • Proper Ventilation
Ventilation is vital in controlling the humidity levels in your home. Simple acts like regularly opening your windows and doors when weather conditions permit will allow fresh air to circulate, effectively reducing the humidity. Other simple acts you can do include drying your clothes outdoors and covering your pots while cooking. Another step you can take is to use exhaust fans in your bathroom, kitchen, and laundry room to remove excess moisture and prevent it from building up indoors. Besides, you can consider installing a complete ventilation system to control the humidity levels of your entire house.
  • Invest in Dehumidifiers
Dehumidifiers are a good short-term solution to removing excess moisture in your home. They work by drawing in the moist air and releasing drier air back after removing the water vapour. If you have a basement, you should use a dehumidifier because the air doesn’t always circulate properly.  There are different types of dehumidifiers, each with different capacities. If you have a small space or do not want to spend a lot of money on a dehumidifier for your entire house, you can get the portable kind. On the other hand, whole-house dehumidifiers must be integrated into your home's HVAC system to control the humidity levels throughout.
  • Proper Insulation
If you want to prevent moisture from entering your home, you need to ensure that it is properly insulated. Check your home for any cracks or openings that can allow moisture to enter and use caulk to seal them. If you find any leaks in your roof, foundation, or plumbing, you need to fix them to prevent moisture from entering your home. You must also insulate your walls to prevent moisture transfer and maintain stable humidity levels indoors. Additionally, you can install vapour barriers in your basement and crawl spaces to prevent moisture from seeping into your home through these damp-prone areas.
  • Get Air Conditioning
Air conditioning is vital in controlling humidity levels, as it removes excess moisture while cooling the air. If you decide this is a good option for you, the air conditioner you get must fit your space. An oversized one will cool the air too fast without removing enough moisture, while an undersized one may not be able to cool or dehumidify your home well.
  • Limit Indoor Plants
While indoor plants help to improve air quality, they also add moisture to the air. So, if your humidity levels are already high, consider reducing the plants indoors to control the humidity.
  • Regular Humidity Monitoring
Monitoring your humidity levels is vital to maintaining a healthy indoor environment. You can use a hygrometer to constantly ensure your humidity levels stay between 30% and 60%, or you can invest in modern thermostats with in-built humidity sensors and controls. This way, you will always be aware of your indoor humidity levels and control them accordingly.

Wrapping It Up

If not dealt with promptly, high humidity can affect both your property and your health. That's why you need to ensure that your home is within the ideal humidity levels to ensure you stay safe and comfortable. Plus, if you already have high humidity levels, you can use the different steps discussed to control them before the effects cause unrepairable damage.

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Sam Fitzgerald – CSRT Damp Surveyor

Author – CSRT Damp Surveyor
Sam is a highly qualified and seasoned damp surveyor with over ten years of specialised experience. With a strong academic foundation in building surveying and numerous professional certifications, Sam has established himself as an authority in the field of damp diagnosis and remediation.

At Damp Surveyors Ltd, Sam applies his extensive knowledge to help homeowners across the UK address and solve their damp issues effectively. His approach combines cutting-edge techniques with a commitment to honest, client-focused service, ensuring that every survey and recommendation is tailored to the specific needs of the property.

As a thought leader, Sam’s insights into damp prevention and treatment have been featured in industry publications, underscoring his role as a trusted expert dedicated to maintaining the integrity and comfort of your home.

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At Damp Surveyors Ltd, we stand out as your premier choice for damp survey services in the UK. Our commitment to excellence and customer satisfaction sets us apart. Here’s why you should choose us:

  • Exclusive 3 Free Quotes: We offer a one-of-a-kind optional service where you not only get our top-notch damp survey but also receive 3 free quotes from vetted local companies, giving you peace of mind by saving you thousands on getting the most competitive quotes, and also time researching and contacting other reputable companies.
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Choose Damp Surveyors Ltd as your reliable partner for all-inclusive survey needs. Our top concerns are the health and safety of your property, and we are committed to providing outcomes you can trust.

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