Closing Doors: Better Air Conditioning?

Many people believe that closing the doors of interior rooms will help their AC system run better and save them money. However, this is not the case. Closing bedroom doors can actually worsen the performance of AC systems, which are designed to cool the whole home. Closing the door to a room causes the air to become trapped inside, raising the air pressure. The air then tries to escape through tiny cracks or ceiling vents, leaking into areas you didn't intend to cool. This can cause a rise in temperature and prevent the AC from working properly.

Closing bedroom doors increases energy bills

Closing the doors to your bedroom or other interior rooms while the air conditioning is on will likely increase your energy bills. This is because air conditioning systems are designed to cool the whole home, and closing doors disrupts that process.

When a room is shut off from the rest of the house, the air becomes trapped inside, raising the air pressure. The air then tries to escape through tiny cracks under the door or in the ceiling vents, leaking into areas you weren't trying to cool. This means that the air you have paid to cool is forced out of the house, and an equal amount of unconditioned air is drawn back into the home from outdoors. The more doors that are closed, the more this effect is amplified, with the draw of unconditioned air increasing by 300 to 900% depending on the number of closed doors.

As a result, your air conditioning system has to work harder to cool your home, using more energy and increasing your utility bills. In addition, the unconditioned air that is drawn into the home can bring outdoor pollutants, increase the risk of carbon monoxide poisoning, and create a greater risk of mould and mildew due to higher humidity.

Therefore, it is recommended to keep interior doors open as much as possible when the air conditioning is running to improve the energy efficiency of your unit and maintain a comfortable temperature throughout the house.

It creates an uncomfortable home

Keeping your bedroom doors closed while the air conditioning is running can create an uncomfortable home. When a bedroom door is closed, the air becomes trapped inside the room, causing the air pressure to increase. As the pressure builds, the air escapes through small openings, such as cracks under the door or ceiling vents, and leaks into areas that do not need cooling. This disrupts the airflow and ventilation in your home, making it difficult to maintain a comfortable temperature and fresh air circulation.

The build-up of pressure in a closed room can also lead to a "negative pressure" situation, where air is sucked into the room from other parts of the house or even from outside. This incoming air can raise the temperature of the room, making it uncomfortable and stuffy. Additionally, closing interior doors can worsen the air quality in those rooms, as the ventilation is disrupted, making it challenging to maintain a healthy and comfortable living environment.

Closing bedroom doors while running the air conditioning can also cause inconsistent temperatures throughout your home. Some rooms may become warmer or colder than others, creating uncomfortable hot or cold spots. This can be particularly noticeable in a multi-level house or a house with varying room sizes and orientations.

Furthermore, closing bedroom doors can hinder the performance of your air conditioning system. The increased pressure and disrupted airflow can make it difficult for the system to cool your home effectively, leading to higher energy consumption and utility bills. In summary, keeping bedroom doors closed while running the air conditioning can negatively impact the comfort of your home, create inconsistent temperatures, and increase your energy costs.

It can cause dangerous air quality

Closing the doors of interior rooms with the AC running may be doing more harm than good. When a room is shut off from the rest of the house, a “negative pressure” builds up that sucks air into the room from other areas of the house, or even outside. This raises the temperature of the room and prevents the AC from working properly.

Shutting off interior rooms from the air conditioning in the rest of the house will also worsen the air quality in those rooms. Disrupting the ventilation of a home makes it difficult to move fresh air freely throughout the house. This can cause your home to be filled with dirty, unfiltered air and poisonous carbon dioxide.

As the HVAC system requires large amounts of air to replace the air that is forced out from the pressure of closed doors, outdoor air finds its way in through the easiest path. This is typically a reverse airflow from the chimney, bathroom vents, and water heater and furnace flues. As this air comes into the home, it brings outdoor pollutants, an increased risk of carbon monoxide poisoning, and a greater risk of mould and mildew due to higher humidity.

In general, it’s best to keep your interior doors open as often as possible to allow air to flow freely from room to room. This will avoid pressure problems in your home and will make it easier for your air conditioner to cool your home evenly and with less energy.

It can worsen air quality in those rooms

Keeping interior doors closed when the air conditioning is running can worsen the air quality in those rooms. When a room is shut off from the rest of the house, a "negative pressure" builds up that sucks air into the room from other areas of the house, or even outside. This raises the temperature of the room and prevents the AC from working properly.

Closing interior doors can also disrupt the ventilation of a home, making it difficult to move fresh air freely throughout the house. This can lead to an increase in indoor pollutants, such as mould and mildew, and a higher risk of carbon monoxide poisoning.

In addition, closing interior doors can cause the air conditioning system to work less efficiently. The system is designed to cool the whole home, and closing doors can disrupt this process, leading to increased energy consumption and higher utility bills.

Therefore, it is generally recommended to keep interior doors open as often as possible to allow for proper airflow and ventilation. This will improve energy efficiency, indoor air quality, and overall comfort in the home.

It can cause air to be pulled in through the chimney

Closing the doors of interior rooms with the AC running may be detrimental to your home's energy efficiency and air quality. When a room is shut off from the rest of the house, a "negative pressure" builds up inside, sucking air into the room from other areas of the house or even outside. This is known as "back drafting", and it can cause a variety of issues.

Firstly, back drafting can increase your energy bills. As the pressure in the closed room builds, the conditioned air inside is forced out through small cracks or openings, such as those around windows, walls, ceilings, and floors. This air needs to be replaced, so unconditioned air is pulled in from outside, causing your AC to work harder and your energy costs to rise.

Secondly, back drafting can make it difficult to maintain a comfortable temperature in your home. The closed-off room will be starved of air, becoming hot and stuffy. This creates uncomfortable hot and cold spots throughout your home.

Lastly, back drafting can lead to dangerous air quality issues. As air is pulled into your home through the chimney, bathroom vents, and water heater and furnace flues, it carries with it outdoor pollutants, increasing the risk of carbon monoxide poisoning and mould and mildew growth due to higher humidity.

Therefore, it is generally recommended to keep interior doors open as much as possible to allow for proper airflow and ventilation. This will improve energy efficiency, maintain a comfortable temperature, and ensure healthy air quality in your home.

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