When they first move in, home owners tend to enjoy their pleasant new dwelling, yet quite often by the second year they experience phenomena such as excess moisture, musty moldy odors, and allergic reactions to indoor air contaminants. As the seasons change, humidity issues that lead to damp uncomfortable basements & crawlspaces, or even window condensation upstairs, can become apparent.




Where lack of air ventilation is critical?

More than any other room in the house, the basement can become a repository of unpleasant odors, moisture problems, mold growth and other indoor pollutants. Unventilated basements are not only prone to musty odors and mildew, the basement is also commonly used to store household chemicals, paints, solvents, automobile products and cleaning products slowly release chemicals into the air.

In an unventilated space, these chemicals build up and produce toxic environment. Ventilating the basement exhausts polluted or musty air and draws in fresh air from outdoors.

These are two basic methods for basement ventilation: natural and mechanical, but the second one has definitively huge advantages depending on the technology being used.

Why ventilate?

Due to its position below ground, moisture from the earth seeps in through the floor and walls. When this cold moisture collides with the warmer basement air, condensation develops.

Excessive condensation creates a musty, sour smell and, if left to collect into pools of liquid water, stagnates or produces a breeding ground for mold and mildew spores. Some molds are toxic and hazardous to the health of the home’s occupants.

The EPA (Environmental Protection Agency of USA) reports that certain types of mold, particularly black mold, can aggravate or cause allergic reactions, asthma attacks and symptoms of influenza. The EPA recommends that homeowners reduce or remove any water leaks or moisture problems and ventilate the basement. A constant influx of clean, fresh air inhibits mold and mildew growth.

The EPA suggest as well that homeowners maintain an environment below 60% of humidity to inhibit the growth of mold and mildew in their basements.

Natural method

Natural ventilation makes use of natural air currents, but this type of ventilation works only for basements with windows that are strategically placed and able to open and close. While the natural method conserves energy.

Its does require more work. Windows must be opened at regular intervals and closed during times of rainfall, high outside humidity level, or at night because of the air features change over from dusk to dawn. For best results, window should be opposite each other across the basement space, following the drafts of the basement.

If the basement is continuously wet, the natural method is most likely insufficient, and a more mechanical system may be required.

Mechanical method

Mechanical ventilation uses fans and vents to exhaust existing basement air and bring in fresh air. The simple but not very efficient type may be placing small window fans in opposite windows or as technical as installing an exhaust fan with ventilation pipe to bring outside fresh air.

The most sophisticated and computerized product will create a permanent air circulation inside the basement and replenishing the fresh and clean air from upper levels by controlling on time indoor air feature.

Mechanical ventilation is also a requirement for homes testing positive for radon, an odourless gas that is the leading cause of lung cancer in North America among non-smokers.

What fit to basement apply for similar reasons to crawlspace even if this space is not a room but integrated in home envelop and impact living spaces with stagnant moistly stale air raising to main level.

Because clean air matters with every breath.