
Energy bills fluctuate quite a bit throughout the year. As the winter months approach and you consider heating your home, you may want to close HVAC registers to save money on bills and only heat rooms you use. But will closing your HVAC registers really save you enough money on your energy bills to be worth it?
Our team at Energy Masters wants you to know why closing off your HVAC registers might not be a good idea for your home’s system and what may happen if you keep them closed for too long.
Why Would You Close Your HVAC Register?
Many people believe that you should close HVAC registers in unused rooms to save money on your electricity bill. Often, homeowners choose to close off HVAC registers because they believe the heat from the closed-off room will transfer to other rooms, warming up their home more quickly. You may also find yourself closing off HVAC registers if the room feels too warm or cold in an attempt to regulate the temperature.
Should You Close HVAC Registers In Unused Rooms?
While you might think it’s a good idea to close HVAC registers in unused rooms, your registers should never be closed off more than 75%. Though this seems like it may work to warm other rooms more quickly or change the temperature of the room, it may end up doing more harm than good for your home’s HVAC system.

What Happens When You Close HVAC Registers?
HVAC professionals create your home’s HVAC system with your home’s exact dimensions in mind. Each vent and pipe is essential for it to function properly. However, when you close HVAC registers in unused rooms, you throw off the airflow. When you close registers, you force your system to work on overdrive, trying to balance out the temperature in your space. Over time, this may lead to a build-up of static pressure in your vents, which can cause substantial damage to your system.
What Is Static Pressure?
Static pressure is the resistance of airflow in your home’s HVAC system. In order for the system to function properly, there needs to be more air pressure than static pressure in your HVAC vents. When you close HVAC registers in unused rooms, static pressure begins to build up. If this pressure build-up is not addressed, you may begin to notice problems with your vents and HVAC.
There are several signs to look out for if you believe you have static pressure building up in your HVAC system. These signs of static pressure include the following:

- Noisy HVAC: While it is running, your HVAC system should not make too much noise. However, if you close HVAC registers and notice your system is noisier than normal, it might be a sign of static pressure.
- Increasing Energy Bill: While increasing energy bills aren’t automatically a sign of static pressure, it is a good idea to keep an eye on your energy bill if you believe you are dealing with static pressure.
- Inconsistent Heating And Cooling: If you notice patches of especially hot or cold air in your home, it may be a result of static pressure in your HVAC system. The system may be throwing out more air in one room than in another.
What Does Static Pressure Do To Your HVAC System?
Static pressure can cause really substantial problems for your system if you don’t catch it soon enough or ignore the signs. Problems caused by static pressure build-up in your system include the following:
- Premature system breakdown
- Leaks in your system
- Carbon monoxide leaks from a damaged heat exchanger
- Mold and mildew growth

Maintaining Your Home’s HVAC With Energy Masters
It is important that you are careful when adjusting HVAC registers in your home. As we mentioned above, registers should never be more than 75% closed to protect your vents from static pressure. You should also be mindful of your vents when moving furniture over them. You may risk closing them without intending to, which will lead to the breakdown of your system.
If you are dealing with static pressure build-up in your HVAC system, your best course of action is to get in contact with your local HVAC specialist. They can help you maintain your system and ensure it is running at full efficiency throughout the year.
If you are looking for a team of HVAC professionals to care for your HVAC system in the Greenville, SC, area, Energy Masters is the perfect team for you. With years of experience and highly-trained professionals, we are confident that we can help you maintain your HVAC system so your family can live comfortably in your home for years to come.
To schedule an appointment or speak with a member of our team, reach out today.