As HVAC experts at HVAC Services, Inc. we’re skilled at “thinking through” designs to identify risks and dangers or performance and efficiency problems. Sometimes what seems like a convenient duct design runs afoul of our safety and efficiency goals. It creates a situation that, when fully explained, isn’t as attractive as it once was. It might even be dangerous. Attached garages are a big concern for homeowners because dangerous or noxious fumes can enter the main house through poorly sealed walls or doorways. When supply registers are extended into the garage or whole HVAC equipment installations are present there, risks increase. What’s in your attached garage’s air, from vehicle exhaust to chemical fumes, can actually get sucked into your home even when the heat or AC isn’t running.
Positive Pressure, Negative Pressure, and Unexpected Airflow You Need to Know About
Your home is built with layers of insulation and air barriers that keep the energy you’ve invested in heating and cooling from being lost through the walls. When your HVAC system is operating, the air circulates and even generates a slight amount of positive pressure. This prevents air infiltration from outside. When the integrity of the ductwork is broken by a supply register in your attached garage, the air barrier is breached. If the HVAC system is idle, the supply register will actually be the conduit by which your home draws air from your garage. This is thanks to the negative pressure indoors as compared to the garage. A good gust of wind that blows against your garage door can lead to unseen airflow from your garage to your bedrooms, living room, kitchen, or wherever your ductwork leads. Just like an open window, the supply register will allow noxious fumes, smoke, or other undesirable contaminants into your home.
Carbon Monoxide, an Overriding Concern
Normally, as HVAC professionals, we’re concerned with keeping carbon monoxide from a poorly burning furnace from circulating in your home. Furnace systems are well designed to prevent this, unless defects such as a heat exchanger crack or flue damage are present. There’s a problem that occurs when your garage has a direct pipeline to your ductwork through a supply register. Any carbon monoxide generated by vehicles, power tools, generators, and other devices running in your garage can enter your home. Carbon monoxide is not only deadly, it’s difficult to detect and can have a cumulative effect on your body. Any risk is an unacceptable risk. Your home should have detectors that sound an alert if carbon monoxide is present, but they are localized and the problem could be present somewhere else. The potential consequences make carbon monoxide risk avoidance absolutely necessary.
Bad Air Sources and Your Indoor Air Quality
Many homeowners invest in indoor air quality equipment for their HVAC systems. These adjust humidity, provide ultra-fine HEPA filtration, neutralize contaminants with UV lights, and pull pollen and other airborne particles out of the air. When you break the loop of your home’s airflow with a garage supply register, you introduce problems in your indoor air quality system. You might pull in volumes of pollen directly from outdoors or introduce wildfire smoke from outside air. Air from the garage can also bring unexpected contaminants. Examples include volatile solvents, stray fuel vapors, pesticides, smoke, and other contaminants that are supposed to be limited to the garage for your safety.
Garage Safety Standards are Different
A typical garage is not sealed for energy conservation and air draft prevention. It’s considered an appropriately drafty space where fumes from chemicals and engines dissipate over time. The garage is typically where you store items that aren’t safe for your basement or other locations in your home. Attached garages are less appropriate because they have doorways and other connections to the home, but the concept still remains. Installing supply registers to provide access to your home’s HVAC ductwork lowers your home’s air quality standards to match those of your garage. If a homeowner wants to properly extend heating and cooling from the main house to a garage space, it should be properly prepared. The insulation, air barriers, and other energy-saving preparations typical for living spaces should be used. These measures make your garage a part of your home, rather than connected to the outdoors.
Breezes, Dryer Vents, and Other Ways Air Gets Pushed or Drawn In
Outdoor air can enter through your home’s dryer vents, bathroom fan exhausts, and other gaps in your air sealing. Many homeowners either block these when they’re not in use or provide a mechanism to automatically shut them when there is no dryer exhaust or fan activity to provide pressure. Home vents are carefully located, so they are unlikely to bring harmful air in from the garage.
Garages, Attics, and Storage Closets, Risky Locations for Your HVAC Equipment
If your HVAC equipment or air handling system is located in your garage, along with any ductwork transiting your garage space, you also have the potential for dangerous distribution of toxic air. Ask the experts at HVAC Services, Inc. for solutions that can help you preserve your home’s air quality. Attics that aren’t within your home’s air-sealing design are also vulnerable places for equipment placement. Be careful with heating and AC equipment that’s located in closet spaces or other potentially mixed-use spaces. Storing cleaning chemicals or similar materials nearby can have harmful effects on your home’s air. Even in a standard basement installation, you may find that nearby odors are drawn into your airflow and need to be addressed. A particularly critical example is a gas leak from your furnace, which can circulate and produce gas odors throughout your home, even when the AC is operating.
Meeting Your Heating and Cooling Needs in Safe and Effective Ways
If what you’re trying to do with supply registers in attached garages is comfortable in your garage, our experts can provide solutions that keep your family safe while still meeting your needs. We’ll help you maintain your whole-house HVAC system’s airflow and pressure balance for top air quality and safety. A ductless mini-split AC or heat pump provides effective and efficient cooling, even adding heating if you like. Finding great HVAC solutions is exactly what we do at HVAC Services, Inc., every day. Ductless mini-split units deliver comfort directly to the space, whether it’s your garage, workshop, home office, or in-law apartment. You can heat and cool a separate space without connecting it into your home’s HVAC system. Airflow is only through the distribution head in each room, and thermostat or even motion sensing control lets you manage your energy costs for that space separately.
Staying Safe with Professional HVAC System Care
Together, the team at HVAC Services, Inc. has over 425 years of experience and a lot of wisdom as well. We can help you avoid creating dangers in your HVAC system and identify existing ones. Best of all, we can provide a solution that accomplishes your home, garage, workshop, and even pool house HVAC goals safely, effectively, and efficiently. Call us and let our versatile HVAC experts provide the solutions you need!