Home Ventilation Solutions: From Basics to Best Practices

Alan Stephens • October 1, 2025

Tips for creating a healthier living space

WHAT is ventilation?

Ventilation refers to the exchange of indoor and outdoor air. Without proper ventilation, the indoor air of a well-insulated home can accumulate harmful pollutants, such as moisture, mold, carbon monoxide, radon, bacteria, and viruses.  Proper home ventilation starts with an understanding of how to minimize the amount of moisture and other pollutants created or brought into your home. Then, the strategic use of your HVAC system, exhaust fans, dehumidifiers, and humidifiers can help you create and maintain optimum interior air quality.

 

WHY is ventilation important?

Proper ventilation helps keep a home energy-efficient, safe, and healthy. A well-designed and functioning ventilation system plays a significant role in a home’s longevity. Proper ventilation and air exchange can help prevent mold, deterioration of building materials, and growth of wood-destroying organisms. Maintaining proper humidity in the home also improves the efficiency of HVAC equipment which can lower energy consumption and longevity of the system.

 

Even more important is the role ventilation plays in your family’s health. Particularly with the increasing amount of time spent indoors, maintaining air quality can promote a healthier living environment. Carbon monoxide gas, generated from the combustion of natural gas, propane, and wood fuels, needs to be exhausted outside of the home. Bacteria and viruses love moisture and warmth, so maintaining proper levels of humidity can help limit their growth.

 

Ventilation is important in all homes, but especially in newer construction since new homes generally have more insulation and tight air seals that prevent air movement.

 

WHAT are the basic approaches to home ventilation?

·     Natural ventilation provides uncontrolled air movement from windows, doors, or cracks in the home. Inconsistent, variable, and difficult to maintain desired interior conditions, fewer homes today are designed for, or operated with, natural ventilation.

·     Spot ventilation uses individual, localized exhaust fans to quickly remove pollutants and moisture at the source. Range hoods over stoves and bathroom exhaust fans are examples. Can be used in conjunction with natural and whole-house strategies.

·     Whole-house ventilation entails using one or more fans and duct systems to exhaust stale air and/or supply fresh air into the house. Whole-house ventilation systems provide controlled, uniform ventilation throughout the house.

 

Regardless of the strategies utilized to ventilate your home, as mentioned earlier, it’s important to reduce the amount of moisture entering your home. Moisture intrusion is the single largest factor that affects home maintenance and longevity. Limiting it requires a comprehensive awareness and strategy that includes:

·     Stop air leaks: when warm, moist air meets cold surfaces condensation is formed. To prevent this, you should seal all air-leakage paths between living spaces and other unconditioned parts of the house, such as attics, basements, and crawl spaces. Insulation alone cannot prevent moisture problems.

·     Eliminate water entry points: maintain your roof in good condition. Roof gutters and downspouts should be kept clean and should drain water sufficiently away from the house. Regularly check any caulking and flashing around windows, doors, tubs, and showers and add or replace as needed.

·     Ventilate indoor moisture: Just by breathing and perspiring, a typical family adds about three gallons of water per day to their indoor air. If a clothes dryer is not vented outside, or if the outdoor vent is closed off or clogged, all that moisture will enter the living space. Keep your ventilation system running efficiently with regular service and maintenance (including checking and changing the filter!) to ensure proper operation.

·     Attic ventilation and insulation: Kitchen and bathroom exhaust fans should lead directly outside and should never be vented into the attic, where moisture can cause serious problems and pose potential health problems. Proper and consistent attic insulation depth should be maintained to control potential condensation from warm, interior air meeting the cold attic air.

·     A dehumidifier can effectively reduce moisture levels (though it will increase your energy use).

 

WHERE in the home is “spot ventilation” most critical?

As mentioned above, whole-house ventilation has become the most common approach to ventilating homes today, with centralized HVAC systems being standard. However, “spot ventilation” is generally provided in kitchens and bathrooms as these areas are responsible for a significant amount of moisture and air pollutants inside of the home.

 

Kitchens: We all appreciate the delicious kitchen aromas of a home-cooked meal. However, to avoid those odors lingering or spreading to other areas of the home, strategically placed exhaust fans should be installed to remove particles, smoke, carcinogens, and odors from your indoor air.

 

The exhaust fan is usually directly over the kitchen stove and is installed in a range hood or cabinet. It can also be integrated with a microwave oven or mounted on the wall. The fan should always be ducted to exhaust outside of the home, not into the attic, crawlspace, or another interior area. Installations that exhaust back into the same room will filter grease and large particulates but have limited effectiveness in removing moisture generated by cooking processes.

 

When choosing a kitchen exhaust fan, the size should be appropriate for the size of your range. Generally, a 120 CFM fan is adequate for an overhead vent hood. This is a situation where bigger is NOT always better, however. High-capacity exhaust fans are not only loud but can create a negative pressure in the home which can lead to back-drafting of chimneys, potentially bringing dangerous combustion exhaust gases into the home.

 

Bathrooms: While bathroom odors are the most obvious justification for running a bathroom exhaust fan, the moisture, water vapor and steam created during an average shower or bath have far greater implications for home maintenance. If that warm, moist air isn’t properly exhausted, it has the potential to cause mold, mildew, and damage to the walls and structure of your home.

 

When choosing a fan for your bathroom, be sure to consider the size of the room. Generally, for bathrooms less than 100 sq. ft. in size, an exhaust fan should provide a minimum of 1 CFM per square foot of floor space. For bathrooms with a whirlpool-type tub, a higher-capacity fan is recommended.

 

Ceiling-mount bathroom exhaust fans are generally connected to an exhaust duct that runs through the attic or between floors. These are the most common types of fans.

 

Wall-mount bathroom fans are designed for rooms where venting through the ceiling isn’t possible. These fans typically vent directly through the wall to the outside with little or no exhaust ductwork.

 

Basement/slab: Radon is a naturally occurring decay product of uranium that emanates from rocks and soils under the earth’s surface as a colorless, odorless gas. As it’s produced, radon can concentrate in enclosed spaces, such as houses. The majority of radon in homes permeates through cracks in the foundation or slab. Other common pathways include plumbing penetrations and sump pumps.

 

If a home radon test indicates an ambient level of radon that is above the threshold (amount considered hazardous), mitigation will normally involve the installation of a sub-slab depressurization system. This generally involves the insertion of one or more suction pipes through the floor slab into the crushed rock or soil underneath and includes an exhaust fan that creates a negative pressure to pull air (and radon) from under the slab and exhaust it to the home’s exterior.

 

Maintenance of radon mitigation system exhaust fans is generally minimal, however, as a homeowner, it’s important that you check the system’s manometer regularly to confirm that the fan is operating properly.

 

WHAT are some other exhaust fan considerations:

 

Exhaust ducting: When designing or installing an exhaust fan, be sure to plan for the proper exhaust duct size. A hood for minimum extraction in most kitchens should have at least a six-inch duct exhaust. The hood should also be flexible enough to connect the duct work on the top or the rear of the unit. Ducting should have as short and straight a run to the outside as possible, so the fan works more efficiently. If the exhaust duct must turn or go a long distance, you might want to consider a fan with a larger capacity. The best exhaust paths are made using solid, smooth ducting—not ribbed or flexible which impede airflow. Where the ducting runs through unheated spaces, it should be properly sealed at every seam and insulated to avoid the cold air surrounding the ductwork causing condensation and leaks.

 

How long to run the exhaust fan: To completely remove the pollutants and moisture created during a kitchen or bathroom event, it’s recommended that exhaust fans be left on for 20 or 30 minutes after the source of the pollution has been eliminated. Optionally, you can install a timer on the exhaust fan switch to ensure it runs for the desired time. While running the exhaust fan, keep a door or window open slightly. If the bathroom is sealed while the fan is on, there is not enough air to draw air and properly exchange it—and the fan can’t push the moist air outside. If the airflow in your bathroom is restricted, your fan’s power will be reduced significantly.

 

Maintaining your exhaust fans: Dust, grease and other particles will accumulate on exhaust fan blades and other components, reducing the fan’s performance and longevity. Cleaning of the exhaust fan should be done as needed, but you should remove the cover and check it for dust build-up at least twice per year

You can also test your fan’s strength by holding a tissue up to it when it’s running. If the fan’s exhausting will hold the tissue in place, it’s probably working as required. If not, consider replacing it.

 

Understanding and maintenance of your home ventilation systems is an important responsibility of any homeowner. Proper design and operation can improve the longevity, air quality, and comfort of your home. A home maintenance inspection can help identify opportunities to optimize your home’s ventilation systems to ensure an energy-efficient, safe, and healthy home environment.

By Alan Stephens December 3, 2025
A valuable tool for revealing hidden issues.
By Alan Stephens November 5, 2025
November is National Child Safety and Protection Month. Data shows that accidental injury is the leading cause of death in children less than 14 years old, with over 30% of those injuries occurring in the home. Some of the most common home-related injuries, and where they happen, include: Burns – in the kitchen or at the barbeque grill Suffocation – in an unsafe sleep environment, foods (i.e., hot dogs, grapes), small items (i.e., batteries, coins), and items that can strangle or entrap Drowning – in the bathroom, kitchen, swimming pools, or hot tubs Cuts – in the kitchen, garage, or garden shed Falls – on stairs, from high windows, or from tipping furniture Poisoning – under the kitchen sink, in the garage or garden shed, the bathroom medicine cabinet, or anywhere medicines are stored (such as a purse or car console) As much as a parent thinks that they’ll be able to always watch their young children closely, even with the best preparedness and intentions it only takes a few seconds for an inquisitive baby or toddler to put themselves in an unsafe situation. Accidents do happen, even when precautions are taken, so being prepared to react calmly and quickly can help minimize the severity of any injury. To provide a safe home environment and reduce the risk of injury to children (and grandchildren) it’s important to look for and address potential safety risks in all areas of the home – inside and out. For homes with infants and toddlers, try to look at the world from their perspective. Spend some time crawling around on your hands and knees and try to find anything that could cause an injury. If you have older children, you could even involve them in a challenge to help you find potential hazards with prizes or rewards for their input! The following checklists for each area of a home can help your awareness of potential hazards and options to prevent them: General: Keep an “emergency contact” list for your pediatricians, doctors, poison-control center, neighbors, and close relatives. While it’s relatively easy to find these on your cell phone, a printed list prominently located will be easily available to you or others who may be watching your children. Learn CPR (cardiopulmonary resuscitation) and the age-appropriate Heimlich maneuver. Purchase or assemble a first-aid kit with a supply of bandages, tape, gauze, antibiotic cream, antihistamines, and any specific emergency instructions someone might need. Confirm the placement of smoke and carbon monoxide detectors in the proper locations throughout the home and, depending on their type, change the batteries regularly. Have a working fire extinguisher available and make sure you know how to use it. Kitchen: Childproof latches that secure doors and drawers automatically when closed All knives, forks, scissors, and other sharp tools stored in a latched drawer Dishwasher lock to prevent opening and access to dangerous objects Oven-door lock and stove-knob protectors Anti-tip bracket installed on the range Locate chairs and stepstools away from the stove When stovetop cooking, use the back burners or turn pot handles away from kids’ reach Glass objects stored out of reach Countertop appliances and cords out of reach Garbage kept in a cabinet or other childproof location Under-sink cleaning supplies and other unsafe products in a childproof cabinet Plastic bags stored out of reach or in a childproof cabinet or closet Refrigerator magnets or other small items out of reach Working fire extinguisher located in a childproof but accessible location Tables free of tablecloths within a child’s reach Highchair equipped with a safety belt and strap between legs Child's Room/Bedroom: Safety belt on the baby's changing table Crib slats less than 2-3/8” apart Crib hardware secure and free from sharp edges Crib mattress properly sized (no gaps around edges) Crib free of a “drop-side” Crib free of pillows, bumper pads, stuffed animals Hanging mobiles with string or ribbons out of reach Cordless window treatments (or cords secured out of reach) Electric cords >3’ away from the crib Dresser equipped with an anti-tip device Non-locking toy chest with slam-proof lid All nightlights clear of bedspreads or curtains Flame-retardant sleepwear with no drawstrings Bathroom: Water heater set below 120°F Childproof latches on all drawers and cabinets Razors, scissors, and other sharp objects stored out of reach Medications, cosmetics, cleaners, nail polishes, and other toxic materials out of reach and stored in a childproof cabinet or drawer GFCI protection on all outlets Toilet-lid lock and always left closed when not in use Hair dryers, curling irons, and electric razors unplugged and stored securely when not in use Nonskid bottom of shower and bathtub Garage & Laundry Area: Tools and supplies used for cleaning, auto maintenance, pool care, gardening, and lawn work stored out of reach or in a secured location Garbage and recycling bins covered and secured Bleaches, detergents, and other cleaning products in their original containers and stored in a locked cabinet Laundry detergent pods out of reach and out of sight Clothes washer and dryer doors kept closed when not in use Walls & Floors: No peeling or cracking paint on walls No nails or other sharp or removable hardware within reach Mirrors and frames out of reach Doors & Windows: Doors equipped with finger-pinch guards One-piece door stops (or rubber tip removed) Doorknob covers on doors you don’t want your child to enter or exit Childproof locks on sliding doors Decals on glass doors Furniture located away from windows Safety guards on upper-story windows Window blinds and curtains free of cords or cords secured out of reach Furniture: Bookshelves and other furniture equipped with an anti-tip device Protective padding on corners of coffee tables Hand-me-down toys and equipment confirmed for no recalls TV’s mounted securely to the wall Childproof drawers with stops to prevent drawers from falling out, free of hazardous objects Stairways: Approved and mounted safety gates at the top and bottom of every stairway Stairs free of loose carpeting or objects Balusters on stairway guards with less than 4” spacing Railings and balusters secure Electrical: All unused outlets covered with safety plugs Cord holders to keep longer cords fastened to walls Extension cords not a tripping hazard and unplugged when not in use Heating & Cooling Elements: All radiators and baseboard heaters covered with childproof screens Gas fireplace valves and switches secured or out of reach Fireplace screen or barrier in place Electric space heaters >3’ from beds, curtains, or flammable materials Outdoors/Backyard/Pool: Walkways and outdoor stairways well lit Stairway risers closed to prevent entrapment or falls Sidewalks and walkways free of major heaving cracks or tripping hazards Swing sets free of sharp edges, rust, or splintering wood Swings, slides, and other equipment securely fastened Softened ground below swings (i.e., sand, mulch, rubber mats) to absorb the shock of a fall Min. 5’ climb-proof fencing surrounding the pool Pool access with a self-closing gate and childproof lock Alarm on door accessing pool from the house Ladders removed from above-ground pools when not in use Other Safety Issues: Checked, confirmed, and removed any poisonous houseplants No smoking rule to protect your kids from secondhand smoke Testing and required mitigation for radon, lead, asbestos, mold, and other air quality issues Guns kept in a locked cabinet, separate from the ammunition A Home Maintenance Inspection can help identify safety hazards in the home and provide a strategy for confirming a safe home environment for your family.
By Alan Stephens September 3, 2025
Cooler weather is on it's way...