Home Ventilation Tips: 5 Signs You Need a Dehumidifier

Luckily, humidity problems can be remedied through the use of a dehumidifier, either a whole-home model or portable unit that can be used specifically in problem areas of the home. Be on the lookout for the symptoms below which indicate excess moisture, as they are signs you need a dehumidifier in your home.

But you are probably wondering: “If the temperature is comfortable in my house… how do I know if I need a dehumidifier?”

What are the signs?

  • Condensation on windows and glass doors – When an indoor environment is too humid, condensation will collect on glass in the room. It can look like fog on the windows or you may even see streaks of water droplets sliding down your window panes as moisture collects.
  • Mold spots on walls and ceilings – The cause of some mold growth is easy to determine, such as that growing around a leaky toilet or under a leaking sink. When there is excess moisture in the air inside your living areas, mold can grow on surfaces like walls and ceilings. Bathrooms are a typical trouble spot, as proper ventilation is not always in place to divert the steam created by running hot water. Steam rises and settles on the ceiling and in the corners of the walls, so be sure to keep an eye on these areas. Moisture can also be trapped in closets, basements, and other poorly ventilated areas of the home, leading to mold growth.
  • Musty odors – A musty odor is a tell-tale sign that mold and mildew growth is present. Excessive humidity in the home can cause mold growth, leading to this odor.
  • Ground water dampness – Water run-off associated with the rainy season can lead to excess moisture in the home. If water run-off is not diverted properly, it can flow back towards your home, causing moisture problems in basements and other areas of the home.
  • Water stains – Water stains on walls, ceilings, floors, and other surfaces are a red flag for excess moisture in the home. As humidity builds up in the home and gathers on surfaces, it will create water marks and stains.

Though humidity is one issue your home may experience, we also want to delve a little deeper into the more comprehensive topic of ventilation; the “V” in HVAC.

a woman opens a window to ventilate the apartment. fresh air in the room

What Do You Mean When Mean When You Say Ventilation?

Home ventilation deals with how air circulates between the rooms in your home and the outside environment. It helps move air through your home, purifying it and removing unwanted dust, allergens, and smells. It also helps control moisture and humidity, keeping the air in your home fresh.

Why Is Home Ventilation Important?

Proper home ventilation keeps your family healthy and home comfortable. Whether it’s via a forced air system, natural ventilation, or other mechanical means — which we will get to later — home ventilation systems rid your home of airborne particles like dust and allergens that can cause serious health issues.

Additionally, ventilation systems control the humidity and moisture levels in your home, saving you from uncomfortably humid rooms and structural damage caused by excess moisture.

What Kind Of Home Ventilation Options Are There?

Depending on the age of your home, the climate you live in, and your ventilation needs, you could either have mechanical ventilation, natural ventilation or a combination of the two.

Natural ventilation uses the gaps, cracks, and small holes in your home’s structure — along with windows and passive vents — to allow air to move uncontrolled throughout your home. Usually found in older homes, these types of systems dilute the air pollutants in your home enough to keep your family healthy.


  • Cheap
  • Often already built-in older homes


  • Cannot be controlled
  • Does not ventilate home uniformly
  • Can be expensive when temperature control is an issue
  • In mild weather, it may not remove enough pollutants from the air
  • During cold or windy weather, your home may become drafty and uncomfortable

Mechanical ventilation uses things like fans, range hoods, and whole-house ventilation systems (forced air systems, etc.) to move the air throughout your home. Since much of the emphasis in home-building today is energy efficiency, many homes are built to be “airtight.” While this is good for combatting energy leakage, it often means mechanical ventilation systems are needed to circulate air throughout these “airtight” homes.


  • Effective for uniform ventilation
  • Air is purified using filters
  • Can be either whole-house or single-room systems
  • Can be integrated into heating and cooling systems like forced air units


  • The bigger these systems are, the more energy they use

Mixed ventilation systems are actually used in most homes built over the last 30 to 40 years. Even homes in temperate climates that rely on natural ventilation for cooling use mechanical “spot ventilation” to remove excess air pollutants and moisture at the source. For example, your home ventilation system may be natural, but you most likely have range hoods in your kitchen and exhaust fans in your bathroom.


  • Provides more complete ventilation for the entire home
  • Can save money by only using mechanical ventilation where it is necessary


  • The natural ventilation in your home may not be enough in high allergen seasons

How To Improve The Air Quality Of Your Current Ventilation System

If you are experiencing poor ventilation, there are a few things you can do to help circulate the air and remove pollutants from your home:

– Consider purchasing a high-efficiency furnace filter for your heating and cooling unit. High efficiency furnace filters trap more microscopic particles than typical furnace filters, keeping the air you breathe healthier. Look for MERV 8 and above for your home.

– Support your ventilation system with tools like air cleaners, air purifiers, humidifiers, and dehumidifiers depending on your ventilation needs. These forms of mechanical ventilation can be used as spot ventilation to help keep the air in rooms you spend the most time in cleaner.

– Call an HVAC professional. If nothing else is working to increase the ventilation in your home, you may have problems with your primary ventilation system or your home’s natural ventilation.