How the subfloor impacts Air Quality

Sub Floor Showing Ventilation Duct

Is The Air Quality Inside My Home Affected By The Subfloor? 

When air pollution is mentioned, you rarely think of the air in your home. 

Mould, moisture, and other pathogens can be introduced into your home through the subfloor. These things could trigger allergies every time you breathe in the air that comes up.

This guide covers some of the factors that may impact indoor air quality. We also look at how your subfloor can affect the air quality inside your home. 

What Impacts Indoor Air Quality?

Indoor air contaminants can come from within your house or outdoors. 

Some of the sources of indoor air pollution include:

  • Contaminated Outdoor Air

Living in an area exposed to general vehicle exhaust or industrial pollutants can contaminate your indoor air. In addition, areas with plenty of fungal spores, dust, and pollen can also affect indoor air quality.

  • Emissions From Close Sources

Things like odours from dumpsters, exhaust from vehicles or garages, loading docks, and damped debris near your house can also contaminate indoor air. 

  • Soil Gas

Volatile organic compounds are released as gases from solids or liquids. Leakages from underground fuel tanks, previous landfills, pesticides, and radon can also contaminate the air. 

  • Moisture

Moisture is never termed an indoor pollutant, but it’s one of the most harmful pollutants. Mildew and dust thrive where moisture settles, and these contaminants trigger allergic reactions. Things like basement leaks, subfloors, kitchen activities, and rain increase moisture in the air, which, if not regulated, can affect your indoor air.

  • Pests

Pests like rats, mice, termites, and spiders hide in basements and crawlspaces as these places are undisturbed. Unfortunately, the pests’ droppings and urine can introduce pathogens that can affect the air quality you breathe.

What is a Subfloor and How Does it Affect Indoor Air Quality?

A subfloor is a narrow space between the floor and the ground your home is built on. It’s usually vented to the outside air. Most subfloors are unfinished and are used as an access point for plumbing, electrical, and ventilation within a home. 

A subfloor acts as an adjoining basement, which allows air to circulate below the house. 

Unfortunately, homes built incorrectly tend to suffer from moisture-related problems because of the space’s surroundings. The moisture also contributes to mould and pest-related infestation. 

How Does a Subfloor Affect Indoor Air Quality

A subfloor acts as an extension of your breathing space in your home. However, despite providing an access point to your electrical and plumbing wiring, your subfloor can also interfere with your indoor air quality as it rises through the floor and vents. 

Here are some ways your subfloor can affect the air you breathe at home.

Increases Indoor Condensation

Most subfloors are filled with dirt, which is drier than the dirt around your foundation. That means your house over a subfloor draws in moisture from the ground. 

When the moisture is inside the subfloor, it evaporates into the air, and the water vapour condenses on floor joists, floor insulation, and ductwork. Indoor condensation makes the air in your house more humid.

Failure to address indoor condensation leads to a stack effect, which means there’s excess moisture and water build-up inside the crawl space. A high humidity level could lead to heat exhaustion and fatigue. 

Promote Mould Growth

Most subfloors lack enough ventilation. Limited ventilation means there’s an accumulation of stagnant air, which is a perfect breeding ground for mould and, as previously outlined, can condensate to promote mould growth.

A good example is during summer. Your subfloor will be cooler than the outdoor air. The minute warm air gets into the subfloor through the vents, it cools and increases the relative humidity. That leads to mould growth as the warm air condenses and settles on floor insulation and ductwork. 

Mould reproduces by making spores, which can be airborne. Inhaling these spores can lead to respiratory issues and cause allergies. 

Interferes With Your HVAC Performance

Many HVAC systems are fitted in the subfloor for easy accessibility. Unfortunately, some of these systems have leaks around the air filter or between the ductwork sections. The leaks reduce the HVAC’s efficiency and send the dirty subfloor air into the system and your house. 

Although your HVAC system may filter the air, it doesn’t sterilize it. As a result, you may end up inhaling mould through the air that comes from your subfloor. 

Foul Odor

You may end up with a musty smell in the air as your HVAC releases air coming from the subfloor. Unpleasant, musty smells signify that you may have rotten wood inside the crawlspace. A foul odour is also a sign of mould on your subfloor. 

How You Can Fix Subfloor Air Quality

Moisture condensations on walls, unpleasant smells, mould, pest invasions, and allergic symptoms indicate that your indoor air quality has been affected due to an unmaintained subfloor.

Here are some ways that you can fix subfloor air quality.

  • Identify the Cause

The first step is to identify the cause of the problem. That could involve checking the subfloor for condensation, mould, or leaks. Next, look for any signs of water under your home. Signs like discoloured timber indicate a water problem in the subfloor. 

  • Remediation

Any cracks around your subfloor can contribute to contaminated air flowing in. Seal up any gaps and cracks with expanding foam or caulk.

Most problems with subfloor air quality come from humidity and dampness. Therefore, you need to address the moisture problem to curb the mould problem. Adding a dehumidifier can help lower the relative humidity in the air. 

  • Rectify The Areas Lacking

If you notice that your subfloor is mouldy, damp, or smelly, you need to consider adding subfloor ventilation. 

Subfloor ventilation replaces the moist air with dry, fresh air. You can opt to have a couple of vents installed in the wall around the building to rely on natural air movement.

Installing subfloor fans also help to create cross-flow ventilation. The system extracts moisture on one side and pulls fresh air from the opposite side of the building through the underfloor area to increase subfloor ventilation. Mechanical ventilation may require professional installation.

Wet subfloors are a perfect breeding ground for mould. Waterproofing is an excellent way to collect the moisture, drain it, and remove it from your subfloor. 

Don’t forget to upgrade and change your HVAC filters regularly.

Unexpected allergies, pest invasions, foul odours, and condensation are all signs that your subfloor could be contaminating your indoor air. Hopefully, you now have an idea of what to look for and how to maintain your crawlspace to ensure that you’re not dealing with moisture or humidity issues that could impact your indoor air quality.

Contact PureProtect at 1800 664 662