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What Are the Safe Humidity Levels Inside a Crawl Space?

The safe crawl space humidity levels are between 50% and 70%. A moist crawl space poses a risk to the building’s structures, as a little-used space can easily develop problems over time that are detrimental to the health of home structures and the home value.

During the summer, the crawl spaces of houses are very susceptible to high humidity, which provides optimal growing conditions for mould. There are several reasons for excessively high humidity. Warm air can enter the ground, which, when cooling down, increases the relative humidity. Water rises from the ground by capillary action, rainwater is diverted to the bottom or pipes running along the bottom of the space may break.

Managing humidity levels in a crawl space is important. Good ventilation and sufficient insulation help prevent moisture from entering the crawl space. Additionally, directing rainwater away from the vicinity of the building, such as with proper drainage systems, reduces the risk of moisture.

If mould starts to grow on the base structures, it is often transmitted at some point to the indoor air of the building and causes symptoms in people. In addition, the supporting structures of the floor are weakened as mould decays organic structures, especially wood.

In new houses, crawl space insulation and mechanical ventilation are often added. Mechanical ventilation often keeps the room warm enough to prevent a sudden rise in relative humidity. Even in an insulated basement, it makes sense to monitor conditions in case of potential problems.

Excessively dry air is often unlikely to be a problem in the basement of a house. However, dry air can dry out wooden structures and cause structural problems.

With Ruuvi, you’ll monitor crawl space conditions effortlessly with your phone.

Measure the humidity of a crawl space and ventilate if necessary

Measuring crawl space humidity levels is easy with RuuviTag It is a small and robust measuring device, so it fits easily into even the shallowest crawl space. With the free Ruuvi Station mobile app, you can check real-time conditions in your crawl space, and also examine changes in conditions from past days. With the Ruuvi app, you can receive alerts about unfavourable conditions and take action to remedy the situation.

A sudden rise in humidity could be caused by a burst pipe or a blocked drain, for example. There are many different ways of draining a space, but good ventilation goes a long way. Ready-made dehumidifiers and ventilation systems are available on the market to help reduce the humidity of the space. With RuuviTag, you can also monitor how dehumidifiers and ventilation solutions are actually working and get the humidity in your crawl space to a healthy level, faster.

It is important to regularly monitor the humidity level in the crawl space and respond immediately to any moisture deviations. It is advisable to seek professional advice if needed in order to plan and implement the appropriate measures to manage crawl space moisture and maintain the long-term health of the building.

Get a Convenient Sensor to Your Crawl Space!
Monitor conditions and receive alerts if something is wrong in your crawl space.

Get a Convenient Sensor to Your Crawl Space!

Monitor conditions and receive alerts if something is wrong in your crawl space.


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