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Tackling Moisture & Humidity Problems in Basements

When it comes to taking care of your home, its contents and the health of the people living in it, there is one problem that may regularly arise - excessive moisture in basements or cellars.

High basement humidity can sometimes be due to poor air circulation and ventilation, an uncontrolled leak, or simply the climate where you live.

High relative humidity can lead to condensation on surfaces and objects, moisture damage to items kept within the space, mould infestation, structural damage, and it can even exacerbate health problems like allergies and asthma.

These issues can be tackled with a basement dehumidifier.

Moisture Issues In Basements

Here is a list of several symptoms of moisture and humidity problems common to basements:

1. Humidity level greater than 50 to 55 per cent – Easiest way to find this out is using a hygrometer, which are inexpensive. If the hygrometer reads humidity levels in your basement greater than 50 to 55 per cent, then your basement is more humid than it should be.

2. Damp feeling – If the air in your basement feels damp on your skin then humidity levels are likely higher than they should be.

3. Odours or musty smell – If your basement has musty smell, it’s likely more humid than it should be. This can signal a variety of different problems, including mold and/or mildew or even possibly rot.

4. Dust mites – High humidity equates to a higher chance of dust mites. The logical conclusion is that if you experience dust mite allergy symptoms in your basement, the relative humidity level in your basement may be too high.

5. Condensation on cold surfaces – If your basement windows, walls or ceiling experience a buildup of condensation, then the humidity levels may be higher than they should be.

6. Frost and/or ice on cold surfaces – If any surfaces in your basement have ice or frost build-up on them, this is yet another indication that moisture levels in your basement are probably too high.

7. Visible moisture damage, rot and decay – Rot can manifest itself in a variety of different ways. Any type of rot is a strong indication that moisture levels in the area are too high.

8. Peeling or cracking paint – Peeling, blistering and/or cracking paint on walls, floors and other painted surfaces can also be an indication of higher than normal humidity levels in your basement or cellar.

If you have noticed any of these signs or symptoms of high humidity in your basement or cellar, then you need to immediately act. Letting the problem linger will only lead to more damage over time.

The Benefits of Using a Dehumidifier In Your Basement

A dehumidifier draws in air from a space and extracts moisture from the air. It then blows the dry air back out into the space, which can collect more moisture. Using a dehumidifier in your basement allows you to manage relative humidity levels, prevent condensation, damp and mould, as well as preserve items stored in the basement from moisture damage.

Desiccant or Compressor Dehumidifier?

Most high quality refrigerant dehumidifiers are capable of operating in temperatures as low as 5°C - though at much reduced capacity to their maximum capability. If your basement is warmer than this on a consistent basis, a refrigerant dehumidifier offers an efficient and cost effective option for drying out your basement. If your basement is consistently around this temperature or even colder, a desiccant dehumidifier offers a more effective alternative.

How Compressor Dehumidifiers Work

Compressor dehumidifiers remove moisture from the air by condensation. They feature metal coils which are cooled using refrigerant gas. Moisture in the air comes into contact with the cold coils, condenses into liquid and is collected by the dehumidifier.

Some compressor dehumidifiers collect this water in a tank, most allow the moisture to be fed to a drain via a hose, and some dehumidifiers have a water pump which automatically pumps the moisture away and out of the basement.

Compressor dehumidifiers are much less efficient at lower temperatures and lower humidity levels than they are at higher temperatures and higher humidity levels. However they provide a cost effective and efficient option for most applications.

How Desiccant Dehumidifiers Work

Desiccant dehumidifiers remove moisture from the air by adsorption. They feature a desiccant material which abosorbs moisture from the air and then releases it as water vapour as it dries. This water vapour can then be vented out of the basement using ducting.

Desiccant dehumidifiers are generally more expensive to run than compressor dehumidifiers, but they offer an effective solution in cold conditions where a compressor dehumidifier would be ineffective.

What are the best features to have in a basement dehumidifier?

There are some key features to look out for in a basement dehumidifier, due to the location it will be installed and your own preferences.

Features to look for in a basement dehumidifier include:

1. Defrost function – High quality compressor dehumidifiers feature automatic defrost, where the machine sends hot gas through the coils at timed intervals in order to melt any ice buildup, which affects the performance of the dehumidifier. This ensures the dehumidifier is able to operate efficiently over long periods and in colder conditions. This is not a function needed by desiccant dehumidifiers.

2. Operating temperature range – If your basement experiences extreme temperatures, it is important to check the manufacturer specified operating temperature range for the dehumidifier you plan on buying, to ensure it is capable of operating effectively in your basement.

3. Condensate Drainage - There are 3 main ways a compressor dehumidifier deals with the condensate extracted from the air. The moisture is either collected in tank, which needs to be emptied regularly. You would need to consider whether this would be practical for you. Or the dehumidifier will have a spout which can be connected to a hose and the moisture can be directed down a drain - this would be suitable if there is a drain in your basement that you can direct the condensate to. Some higher quality refrigerant dehumidifiers also have a condensate pump, which allows them to pump the moisture away from the area, even upwards. This is ideal for continuous use in basements, as the moisture can be pumped out of the basement automatically. Desiccant dehumidifiers expel moisture as water vapour via ducting, so a vent needs to be installed to the outside, allowing the moisture to be ducted away.

5. Humidistat - A humidistat allows you to select a required relative humidity level within the space and it will turn the dehumidifier on and off automatically in order to maintain this pre-set level. This adds convenience and saves money on running costs.

6. Timer – This can be useful if you do not want the dehumidifier to run at certain times during the day or if you want it to run for only a few hours and then shut off automatically.

7. Auto Restart – Should a temporary power outage occur, a dehumidifier equipped with this function will retain all previously inputted settings and automatically restart applied after the outage.