A: You should zone your house when you are faced with challenges such as hot rooms or cold rooms—air distribution that’s not even. Also, homes that have a higher heat source than other areas of the home that you can’t overcome even during cycle.
What you do is install a system that has a zoning board in the attic by the furnace. You install motorized dampers to all the supply ducts in the system—those are wired to the zoning board. You also add an additional thermostat control to the area you want zoned independently.
So, basically, you have a single system with multiple thermostats and dampers that open or close accordingly. It adds precision in the way you condition the air in your home. You can have different people use different setpoints according to their preferences.
Zoned AC In Houston: Is It For You?
Anyone who has lived in Houston most of their life knows that this region is infamous for heat, humidity, and mosquitoes. You combine all three every summer and you get a nasty cocktail of discomfort if your home is not cooled properly. AC in Houston is not a luxury—it’s a commodity. However, if your home is ice cold in the living room but sticky and hot in the kitchen—you have a problem.
In a traditional HVAC system in Houston, you have the outside unit pushing air evenly through various ducts servicing each area. However, certain rooms, due to various factors, may not cool the same as others. Some factors that can make cooling uneven can include:
- Room exposure to high sun
- More in and out traffic outside (such as a mudroom or living room)
- Uneven insulation compared to other rooms
In these situations, you can end up wasting money constantly letting the air run because one room won’t cool as efficiently. This is where zoned AC, in Houston especially, can be quite beneficial. Now, although the initial cost of zoning your home can be between $2k and $4k—it pays for itself in energy savings.
Zoned AC 101: What You Should Know
When we say “zoned system” we aren’t talking about multiple units like in many 2-story homes. Rather, we are talking about a single unit system with motorized dampers for each zone for focused cooling. The components of a zoned system are just like traditional HVAC systems plus a few additional parts.
HVAC System: This is what comes with every system for traditional AC in Houston. You have the furnace in the attic or an HVAC closet and the AC unit outside.
Motorized Dampers: These dampers are what make zoning possible and the damper setup depends on the design of the ductwork. You may have a damper for only the major branches off the main duct, or dampers also for each smaller branch. When you install a zoned system as the home is being built it is much easier than retrofitting an existing system. The dampers are fully adjustable and can be set to open fully or closed all the way. Additionally, you can have them modulated to open and close partially for added control.
Temperature Control Devices: When it comes to controlling each zone’s temperature there are two main options to execute this.
Thermostat – This is the easiest way to control your zones. Simply installing a thermostat in each zone that controls the climate for that particular zone.
Multizone Thermostat & Sensors – This thermostat is similar to a traditional thermostat except that it talks to all the zones from a central location. This is accomplished using sensors that are placed in each zone and they relay the information back to the main thermostat. Additionally, with smart thermostats, you can control all your zones from your connected device.
Damper Control Panel: This panel gets temperature information from each zone and controls the dampers accordingly.
Zoned AC in Houston Can Be Good… Or Bad
A zoned HVAC system is like any other system in your home such as electrical, waste, or drainage system. The success of these systems depends on proper design for them to perform to their potential. An HVAC that isn’t zoned may work harder and run constantly to cool and heat areas of the home that may not need it. It’s kind of like turning on all the lights in your home with one switch instead of switches for each room. You waste electricity lighting rooms you’re not even using and it’s not efficient.
The key to getting the energy savings with a zoned AC in Houston is reducing or stopping the flow of heated or cooled air to unused rooms. For example, you might have cooling to the bedroom zones set to 73° at night and the living room to 80°. This makes sense if you aren’t using the living room at night when you are sleeping. Smart thermostats offer even greater convenience with a zoned system as well.
When a zoned system is designed right, it can cut your energy usage by 20% to 40% depending on your habits. In Houston, the average reduction of energy use comes out to nearly 30%, especially during the cooler months.
Good Zoned System Design Is Crucial
Energy savings are achieved with a zoned AC in Houston by reducing the output of your HVAC system. Therefore, it’s important to start with a variable speed or two-stage unit as the anchor of your system.
The justification for a two-stage system is because this type of system runs at about 65% on low setting and 100% on high. So, two stages run, one at 65% capacity on low and 100% capacity on high. So, when you reduce heating or cooling output in various rooms by a third, you only need about 65% anyway. This means the system runs in the low stage most of the time reducing your energy cost by about a third as well.
Proper ductwork design is crucial to a good zoned system design. Your ductwork should be split to distribute air according to your needs. Without zoning, all rooms would get an equal division of the airflow 100% of the time. You save nothing that way, so proper damper placement and duct routing are crucial.
When using a zoned system, you need either a multizone thermostat or individual thermostats in each zone. This is so that some rooms get a disproportionate amount of the air while lesser-used rooms get little to none. This effectively reduces the total output of the system which saves on energy. Smart thermostats that learn the times the air is needed and in which rooms are a huge help in zoned systems.
Is a Zoned System Right For Your Home?
If your home already has a two-stage or variable system HVAC unit, we advocate for zoning your home. It stops you from wasting energy cooling unoccupied rooms and resolves temperature disparity in the home. Zoning allows you to have target cooling, heating, and an evenly controlled home while saving money.
The Cost To Convert To Zoned
Installing a well-designed zoning system in a home while it’s being built is far less expensive and much easier than in an existing home. Retrofitting your existing system will still pay for itself to varying degrees depending on your situation. Here’s a rough breakdown of the costs:
- Multizone Thermostat: $130 to $625 depending on base features such as LCD touchscreen, WiFi, and Alexa/Google compatibility
- Zone Control Panel: $120 to $195 depending on the features and quality of the panel
- Zone Sensors: $30 to $50
- Motorized Dampers: $85 to $180 for round branch ducts; $160 to $340 for large rectangle trunks
- Wiring: $60 to $160 depending on how many zones you need
- Miscellaneous Supplies: $50-$230 for sealing tape, tools, and other supplies and tools needed to properly install a zoned system
Now, we aren’t including the cost of labor and we don’t recommend you trying this as a weekend DIY project. HVAC design is extremely specific and requires institutional knowledge that HVAC techs spend decades gathering. That being said you really should hire a professional that can take the necessary measures to design the right zoning. A poorly designed zoning system will hinder your efforts to cool and save.
We Deliver The Best AC In Houston
If your home isn’t cooling as well as you’d like in all of your rooms or you’re tired of cooling rooms rarely occupied, call us! We have been helping Houston and surrounding area residents get the most out of their systems while remaining efficient. You don’t have to settle for inefficient AC in your home anymore. Contact us today to get your free consultation for a zoned system installation in your new construction home or retrofitting your existing system.