Proper Ventilation Is Necessary for a Healthy, Comfortable Home

Published on: December 20, 2014
Family doing homework in the kitchen | AC Southeast®

In the Southeast, sufficient home ventilation is essential for keeping your home comfortable through the long months of hot, humid weather and cooler months we see every year. Comfort isn’t the only reason to make sure your home gets good airflow, though. The house itself also depends on air circulation to avoid water and mold issues.

Ventilation Benefits You in Many Ways

Good indoor air quality is the main reason to ensure sufficient ventilation in your home. While having a higher-efficiency air filter in your home’s heating and cooling system helps, not even the best filter can remove all the dust, pollen and mold spores that blow in from outside.

Add to that the contaminants that are produced inside your home, such as dust mites, cooking fumes and possibly insect and rodent debris, and the air filter can easily become overwhelmed. Home ventilation improves air quality more efficiently than a filter by drawing stale, pollutant-laden air out of your home and bringing in fresh, clean air.

Clean air has a number of benefits for your health. If you’re managing allergies or asthma, you’ll experience fewer symptoms with a good ventilation system efficiently removing lung irritants from the air. Even if you don’t have a respiratory condition, clean air matters. For example, indoor air pollution has been linked to cardiovascular disease.

Comfort is another reason to install appropriate ventilation. Without carefully planned air circulation, homes in the Southeast can easily accumulate excess indoor humidity in the summer. That humidity leaves you feeling hot and sticky, so you end up lowering the temperature at the air conditioner’s thermostat. With good ventilation to help you maintain ideal indoor humidity levels, you’ll feel cooler and need less air conditioning, so you’ll save money on cooling.

Besides making you feel uncomfortable, excess moisture in the air can contribute to serious damage in your home. If the wood, drywall or certain other surfaces in your home become damp, they’re a prime target for mold. Mold slowly eats away at the surface on which it grows, which could mean vital parts of your building structure, such as wall and ceiling beams. Well-designed home ventilation removes both mold spores and the excess moisture that supports them, greatly reducing the risk of mold damage.

Natural Ventilation: Simple, But Not Highly Effective

Natural ventilation creates air movement in and out of the house without any mechanical systems. In many older homes, natural ventilation took the form of cracks and gaps around the windows, doors, baseboards and other areas left deliberately to let air flow in and out. The problem with this method is that it lets in more pollutants and humidity than it lets out. It also allows warm air to escape in winter and enter in summer, raising energy bills.

Today, best practices for energy efficiency call for sealing these leaks with caulk or weatherstripping. If an older home that relied on this form of ventilation is air sealed, another form of ventilation should be installed.

For homeowners who like the idea of natural home ventilation, trickle vents are one option. This type of ventilation is known as wind-driven ventilation because it relies on the natural movement of the wind to bring air inside. The vents are typically installed above the windows. Their design allows air to enter without a high level of outdoor contaminants and without creating uncomfortable drafts.

Stack ventilation is another natural ventilation method. A type of buoyancy-driven ventilation, it relies on the natural upward movement of warm air, known as thermal buoyancy, to move stale indoor air toward ventilator stacks on the roof. Unlike trickle ventilation, stack ventilation can still move air on hot, windless days. On the down side, planning and installing this type of ventilation is more involved and expensive than installing trickle vents.

Regardless of the type of natural ventilation you may choose, these systems alone are rarely enough to provide the amount of airflow you need for good health, comfort and a mold-free home.

Spot Ventilation Helps Out in Small Places

Your home most likely has some spot ventilation; most building codes require it. Spot ventilation is the type designed to clear the air in a small area using an electric fan. Bathroom and kitchen fans, as well as the kitchen range hood fan, are forms of spot ventilation.

Unlike natural ventilation, which works automatically, spot vents usually need to be turned on and off. If you tend to forget to use spot vents, choose vents that run on a timer.

In homes with minimal air quality problems, a combination of well-designed natural ventilation and spot ventilation may be enough. Other homes, however, require an additional form of ventilation to maintain optimal airflow and high indoor air quality.

Using spot vents too frequently in an attempt to improve air quality can actually do the opposite. These vents are intended to remove odors, steam and smoke quickly. Used for long periods, they can let in more air contaminants and humidity than they let out.

Whole-House Ventilation: Clean Air Throughout Your Home

When you’re dealing with poor indoor air quality and need home ventilation that ensures clean air in every room, whole-house ventilation is usually the best option. These systems use mechanical fans to move air and a system of ducts to direct air through the house. Whole-house systems come in three main forms:

  • Exhaust-only – These systems pull stale air out of your home, but rely on natural ventilation such as open doors and windows as well as air leakage to bring fresh air in. They’re inexpensive to install, but can raise energy bills because they let out heated or cooled indoor air.
  • Supply-only – These systems bring in fresh outdoor air, but rely on natural ventilation to let stale air out. Also relatively inexpensive, they’re preferred for warmer climates because they tend to cause moisture problems in cooler climates.
  • Balanced systems – These systems include a fan that draws out stale air and another that brings in fresh air. A balanced system gives you the greatest control over the amount of air entering and leaving your home, but because they do more, their installation is more involved compared to exhaust- or supply-only systems.

Because removing too much heated or cooled air from your home would greatly raise the amount of energy it takes to maintain a comfortable indoor temperature, balanced systems are available with components that reduce the amount of energy lost.

An energy recovery ventilator (ERV) is a balanced ventilation system with a heat exchanger at its center. In winter, the heat exchanger removes heat from the outgoing warm air and transfers it back into the incoming outdoor air. That means stale air leaves the building, but heat doesn’t. In summer, the heat exchanger works in reverse to remove heat from the incoming air and send it back outside.

Poor Ventilation Puts Your Health and Home at Risk

While home ventilation has a lot of potential benefits, improperly designed ventilation can cause serious problems. A system that draws out too much air can lower the air pressure inside the house, exacerbating air leaks. With ventilation like this, you may find dust and pollen or cold drafts coming in from places you didn’t even know leaked.

A well-designed home ventilation system moves humid air out of your home, reducing the risk of moisture issues and mold. If the ventilation system brings in too much outdoor air, though, you could end up with moisture problems that didn’t exist before.

Without sufficient home ventilation, carbon monoxide can become an even bigger threat than the debris particles in your air. All fuel-burning appliances, such as gas furnaces and stoves, release some carbon monoxide (CO). Provided the appliances are correctly vented and your home is well ventilated, this CO is directed outdoors. Without good ventilation, however, potentially deadly CO can build up inside your home.

Worse yet, an incorrectly designed ventilation system can pull appliance exhaust fumes from the vents back into your home, a situation known as backdrafting. Consider that even small amounts of CO can leave you with headaches, fatigue, and other chronic symptoms.

To get the most out of your home ventilation system and avoid worsening your indoor air quality, consult a professional before installing any ventilation yourself.

If you’re looking for ways to improve ventilation and air quality in your home, contact us at AirConditioningSouthEast.com for help finding a local contractor in your part of the Southeast.