Benefits of Zoning

What you need to know for temperature control in your home.


If your upstairs is warm and your downstairs is cooler, zoning may be the answer to your home comfort. If one end of your house is warmer than the other end, zoning may be the answer. If you’re experiencing temperature differentials in your house, it may be time to install zoning.

System zoning is pretty simple. It involves multiple thermostats that are wired to a control panel, which operates dampers within the ductwork of your forced-air system. The thermostats constantly read the temperature of their specific zone, then open or close the dampers within the ductwork according to the thermostat’s settings. Not only is system zoning helpful for houses with inconsistent room temperatures, but it’s also great for heating or cooling individual bedrooms based on the desired temperature setting. If you have a usually empty guest room, just shut the door, turn the thermostat down for that room and the system will close the damper.

Let’s use the example of it being warmer upstairs than downstairs. It is typical for the thermostat to be installed downstairs in most homes. When this is done, it is also typical for the upstairs to be warmer than the downstairs. If you have a zoned system, you will have a thermostat upstairs as well. if the thermostat calls for more heat (or cooling, depends on the season) upstairs, then a series of dampers will be opened or closed in your duct system as required to direct more conditioned air to the upstairs area where it is needed. According to the U.S. Department of Energy, system zoning can save homeowners up to 30 percent on a typical heating and cooling bill. Those savings can add up to quite a sum — the Department of Energy also estimates that heating and cooling account for 40 percent of the average household’s utility costs. Because guest rooms and other seldom-used rooms don’t require constant heating or cooling, system zoning allows you to save money by running temperature-controlled air to those rooms only when it is necessary.


When a 2 or 3 story house is built it is not uncommon for there to be just one Air Conditioning/Heating unit to be installed. Ideally, it would have been better to install 2 or 3 separate systems for each floor, or to install zoning when the house is being built. You can’t ignore physics. In a two story home, cool air tends to sink resulting in anywhere from a 2 degree to as much as an 8 or even 10 degree temperature difference between floors, depending on how your house was built.

You can also have a single story home where the temperature can differentiate significantly from one end of the house to another. This is not unusual in homes where the unit is installed at one end of the house and there are fairly long duct runs to the other end of the home. Many factors can contribute to this including using flex duct instead of metal, having your duct in unconditioned space and not sizing the duct runs correctly when installed. When this happens, while the living room near the A/C unit may read a nice cool 68 degrees, the bedroom at the other end of the house may be at 74 degrees. This is where a zone system might make you happier by making you more comfortable.


The good news is that yes, this can usually be done. The bad new is that it can get fairly expensive when done right. Talk to your contractor and find out what is possible for your house. Many homes will benefit from simply having the duct system re-sized or repaired. DO NOT make the mistake of trying to zone things yourself by closing off vents and registers to force  air to another level or to different rooms. This can cause problems with your heating or A/C system. Your system should have been sized to deliver a certain amount of CFM (Cubic Feet per Minute) of air to each room. Unfortunately, many contractors take shortcuts and do not correctly transition or size ducting for optimum performance when first installed.

Sometimes, just making some changes to your duct system can make a difference. It won’t be as dramatic or as satisfying as installing a Zone System, but it can help. BEWARE: There are some contractors out there that will tell you that just installing sensors in each room will make a difference. Not really. All the sensors might do is make the thermostat (no matter where it is located) reach an “average” temperature.

Again, talk to your contractor. If they understand air flow like they should, they will be able to make recommendations.

Stockton Mechanical has installed numerous zoning systems in different configurations for different reasons. For more information (no obligation of course), just give us a call at 505-629-9955We look forward to working with you to help solve any of your air conditioning or heating problems.