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Basement Heaters & Air Conditioners

Basement Heaters & Air Conditioners

Are you trying to convert your basement into a new, comfortable living space but are hindered by installation limitations? Are you struggling with uncertainty about the best cooling and heating system choice?

It is critical to consider the type of air conditioning system you want to install. Each type impacts every aspect of climate control: overall comfort, heating and cooling capabilities, and operating expenses.

Although many air conditioner products are on the market, such as portable air conditioners or ducted central air conditioners, the most efficient solution for climate control in your basement is the ductless mini split system.

With a ductless mini split, you have a system that can provide you with the exact level of comfort you need, high energy savings, and precise control over the temperature inside your basement. Mini splits also offer many other convenience features, such as air humidity control, climate zoning, and easy maintenance.

Basement Cooling and Heating Challenges

Installing an air conditioning system in a basement poses unique challenges due to their below-ground location. When creating living spaces in basements, one of the primary issues is temperature imbalances; basements are frequently subjected to excessive cold and hot temperatures.

Although this phenomenon is partially rooted in natural causes, such as the changing weather conditions and seasons, the temperature imbalances are exacerbated by the fact basements typically have no insulation or protection against humidity.

Environmental characteristics

A typical basement is an enclosed, damp space beneath the home’s main floor. The average height of a ceiling basement in the United States is about eight feet, equivalent to standard above-ground rooms in the rest of the house.

Although the average square footage of a finished basement varies depending on the size of the house, it typically ranges between 500 and 1,500 square feet. In most house designs, the basement is accessible via a stairway near the kitchen. The lower half of the staircase is typically located against one of the basement’s walls to maximize usable space.

The average air temperature in a basement is typically lower than inside the rest of the house due to the concrete foundations, below-ground location, and relatively low sunlight exposure, even with basement windows. Well-constructed basements typically feature rigid foam insulation, giving them two advantages: a layer of heat retention and a degree of protection against vapor penetration.

Humidity levels

Another issue found in most basements is humidity. The recommended average humidity level in a basement ranges between 30% and 50%. However, many regions of the United States reach outdoor air humidity levels far above this number.

According to the EPA, most problems related to high humidity levels begin at 60%. Without climate control to regulate indoor humidity, basements become ideal breeding grounds for mold and mildew.

Other signs of excessive humidity include rotting wooden elements, peeling paint, and generally poor air quality. If you detect a musty, damp, unpleasant scent in the basement, your basement’s humidity level is likely too high, and mold has begun developing.


Basements without a quality ventilation system will be subjected to the whims of outdoor temperature changes. For instance, during the summer, an unventilated basement will accumulate heat. Without ventilation to recirculate the air, your basement’s atmosphere will generate a stuffy or dank smell, making it unsuitable if you want to turn your basement into a living space.

The stuffy air in a basement is also known as stale air and is the symptom of an atmosphere with high CO2 and microbial volatile organic compounds (MVOCs). The combination of CO2 and MVOCs in indoor atmospheres are considered types of air pollution. Breathing such air for extended periods causes coughing, irritation, fatigue, and Sick Building Syndrome (SBS).

The best air conditioning system for a basement should be able to control the temperature, air circulation, and humidity so that the basement becomes as comfortable as the rest of the house.

Common Mistakes When Adapting Basements into Living Spaces

Options commonly used by homeowners range from traditional, ducted central air conditioning to more unconventional solutions, such as window-mounted air conditioners (for basements featuring windows), baseboard heating devices, or even 100% portable AC units.

However, you may be wondering whether these solutions work efficiently or if they are a good option for your home. The best way to tell which solution is the most efficient for your needs is to evaluate your basement and existing air conditioning setup.

Examples of commonly utilized solutions include ducted system extensions and separate heating/cooling systems for the basement. Here’s why homeowners consider these solutions and why they may not address your needs adequately.

Extending the Length of an Existing Ducted System

If you have an existing centralized, ducted HVAC unit at home, you may be tempted to continue using it and extend the ductwork from this system down to your basement. This approach has two primary challenges: load capacity and installation procedures.

Before considering whether you can extend an existing system to an additional room, you must ensure that your system has enough capacity to handle air conditioning in an additional zone, especially in an area as large as a basement.

If your existing central AC system was properly sized for the existing rooms and zones, connecting new ducts to link your system with your basement risks reducing your unit’s efficiency. Adding new ductwork does not increase your system’s BTU capacity. Consequently, it risks becoming undersized.

Even if your system can handle the additional load when you use it to service the basement, the other challenge to consider is installation. Unless you are building a new home and have the luxury of choosing a unit and a duct layout that works for every room, extending an existing system’s duct network may require significant modifications to your house.

The problems may be further exacerbated if your basement is unfinished or your house is older and not originally designed to accept extra ductwork, such as the return ducts.

Even if your HVAC contractor believes it is possible to extend your existing centralized AC system’s ductwork and that it’ll maintain sufficient capacity to control the climate in your basement and the rest of the house, you’ll have to deal with installation costs.

Extending a ducting network is a labor-intensive process that will require multiple days to complete, on top of the material costs. Because the extra ducting costs are equivalent to paying for new ducts, you’ll likely pay similar prices per foot of new ducts.

This option is simply not cost-effective and does not guarantee you’ll get the exact level of comfort you need.

Installing a Separate Cooling and Heating System for the Basement

If extending an existing duct network is too cost-prohibitive or not possible for any other reason, most homeowners resort to the most common alternative: installing separate secondary heating/cooling systems dedicated to the basement.

Typically, such systems are separate, electrically powered devices, such as 2-in-1 space heater/coolers, baseboard heaters, and others. While they can be individually reasonably efficient, these piecemeal solutions have many significant disadvantages: energy costs, limited capacity, limited humidity control, and no integration with your existing systems.

  • Energy costs: Piecemeal heating and cooling systems are mainly designed to be temporary solutions while waiting for a primary climate control system. Relying on these systems long term will cause your energy bills to spike up considerably.
  • Limited capacity: Although such systems are fairly inexpensive to purchase, they rarely possess the capacity needed to heat or cool an entire room; often, they simply cover a small zone inside one room. Basements are larger than most living rooms, making it even more challenging for them to control the temperature adequately.
  • Limited humidity control: In addition to the limited heating and cooling capacity, most such systems have little to no humidity or air quality control. Even if they can adequately heat or cool your basement, they usually have a limited effect on the humidity levels.
  • No integration: Piecemeal heating and cooling solutions are standalone systems, not meant to function alongside a larger or more powerful whole-house air conditioning system. They are isolated from your primary AC unit, requiring you to turn them on or off individually as needed.

What Should the System for Your Basement Deliver?

If you’re looking to use the basement as an extra living space, comfort should be one of your top priorities. However, it is critical to understand that achieving comfort does not mean having to break the bank or spend more than should be necessary.

Ideally, a basement cooling and heating system has the capacity necessary to cover the space and its structural limitations like insulation and humidity. It should also feature the technology needed to improve air quality, control humidity levels to the EPA recommended percentages, and be as energy-efficient as possible.

Critical Points to Remember

Here are some essential factors to remember when considering the best heating and cooling solution for your basement:

  • A basement is a unique space in your home that can get too cold or too hot, depending on the weather, environmental conditions, and related factors.
  • Temperature imbalance in a basement is a common issue and, if you want a truly comfortable living space, it is an aspect that you must tackle effectively.
  • The unique structural characteristics of a basement have a lot to do with this temperature imbalance.
  • Basements’ natural high humidity results in poor indoor air quality and facilitates the growth of mold and mildew, which are harmful to your health. Humidity control is critical to turning a basement into a proper living space.
  • While capable of providing decent results, traditional cooling and heating systems are neither efficient enough nor cost-effective. Their energy efficiency is too low to consider.
  • Using the existing centralized HVAC system at home by extending the ductwork has limitations. Even if you have the opportunity to complete a ductwork extension project, the associated costs risk becoming too high to consider.
  • Using piecemeal solutions to cool or heat a basement does not assure you of achieving maximum comfort. Even if you install them in your basement, using separate systems for heating, cooling, and humidity control will result in higher energy bills.
  • One of the primary challenges of installing air conditioning in basements is finding a system that can effectively tackle the cold, hot, humidity levels, and indoor air issues without being too expensive.
  • Operational performance, energy efficiency, and installation viability are three of the most important things that you need to consider when finding the right cooling and heating system for your basement.

Why Your Basement Deserves a Ductless Mini Split Air Conditioner

Fortunately, there is an HVAC system that can provide your basement the comfort, flexibility, air quality, and humidity control you need to transform it into an ideal living space: the ductless mini split system.

Mini splits are considered one of the best options for basements today due to several factors: system capacity, overall performance, energy efficiency, versatility, and additional comfort and quality-of-life options.

Here are some of the primary benefits of using a ductless mini split system to cool and heat your basement:

Ease of installation

Ductless mini splits require no ductwork to function, meaning you will experience none of the issues associated with ducting like leaks or loss of performance. This advantage is the reason why it is efficient for cooling and heating both in single-zone and multi-zone configurations.

Ductless mini splits can be installed virtually anywhere in your house, including your basement. All that is needed is choosing a location for the outdoor compressor and the indoor units. The most intensive part of the installation process is boring the holes and channels necessary for the power and refrigerant lines connecting the outdoor and indoor units.

Your choice of cooling only or heating and cooling

Mini split systems are available in two forms: cooling-only air conditioners and heat pumps capable of heating and cooling. The most versatile option is the heat pump because it eliminates the need for separate devices for heating and cooling.

High capacity and performance

Mini split air conditioners and heat pumps are designed to operate year-round, providing you with consistent comfort regardless of the weather and outdoor conditions.

Unlike traditional systems with limited cooling and heating capacities, ductless mini splits can work even in extreme weather conditions.

Most ductless mini split heat pumps are powered by inverter technology and have quick heating and cooling functions. This technology allows you to enjoy consistent temperatures, air quality, and overall comfort even under extremely high or low temperatures.

Your mini split will keep the atmosphere pleasant, even when the outside temperatures are too hot during summer or too cold when the climate reaches sub-zero temperature during winter.

Efficient humidity control

Basements without climate control can easily reach unsafe humidity levels, creating a damp atmosphere and favoring the development of mold, mildew, and other contaminants.

One of the primary benefits of using a mini split system for air conditioning is the humidity control function. This function eliminates the need for a separate dehumidification device, keeping your humidity levels at safe numbers. Best of all, dehumidification is an automatic feature; you don’t need to activate the function manually.

Unrivaled energy efficiency

Installing a mini split system lets you save energy and spend less on your energy bills. Unlike traditional AC systems, ductless mini splits are less prone to energy losses owing to their lack of ductwork requirement. Additionally, many mini split models are Energy Star-certified and come with high energy efficiency ratings, whether in terms of cooling and heating.

The powerful compressor and inverter system that mini split systems feature also allows them to reach your desired level of comfort without consuming excessive quantities of energy. This efficiency is because mini splits do not run at 100% capacity constantly, meaning they only consume the needed amount of energy without any impact on your comfort levels.

Here are some industry terms to look for when shopping for mini split products:

  • EER: Stands for Energy Efficiency Ratio. The EER value indicates an air conditioner's theoretical maximum energy efficiency in cooling mode. The higher, the better.
  • SEER: Stands for Seasonal Energy Efficiency Ratio. The SEER rating calculates the energy efficiency of an air conditioner in cooling mode over an average season, providing consumers with a more realistic value than the EER.
  • HSPF: Stands for Heating Seasonal Performance Factor. The HSPF rating calculates the energy efficiency of a heat pump in heating mode over an average season. It is the heating equivalent of SEER.

Advanced air filtration systems for superior air quality

The air filtration systems found in a mini split system’s indoor air handlers are ideal for increasing the air quality in a basement. These filters help reduce ambient humidity levels and block harmful contaminants when recirculating air in the basement.

The multi-stage filtration technology employed by mini split indoor units is more efficient than in any other air conditioning system. Unlike traditional ducted systems, which typically do not feature filtration systems, your mini splits can block various bacteria and allergens, letting you breathe air of higher quality and protect you from many health risks.

The air filtration system also helps combat the unpleasant odors in a non-controlled basement, increasing comfort.

Personalized comfort and quality of life

High-quality mini split systems are highly configurable and possess many quality-of-life features, giving you complete control over your comfort.

With a mini split unit, you can control the system through a handheld remote controller, wired wall-mounted remote controller, or portable central controller. Many mini splits today can even be controlled directly from smart mobile devices via a companion app.

With these controllers, you can turn the unit on or off anytime you want, helping you save more energy. Additionally, mini split systems are designed with sensor or infrared-based functionalities that enable you to personalize your comfort by adjusting the airflow and overall temperature according to your specific needs.

Take Control of Your Basement’s Cooling and Heating

Although controlling heating, cooling, and comfort levels in your basement comes with unique challenges, you don’t need to break the bank to find a usable, cost-efficient solution.

Most of the time, when ductwork becomes an issue, it is easy to invest in a separate system. By going with the traditional systems, you might find yourself using solutions such as a window air conditioner or a portable cooling system for cooling. And, to heat the space, you might quickly opt for resistance heating systems. That’s right; you can turn to a baseboard heater. Or choose an electric heater. Or even a furnace. In fact, you have almost limitless options. But then, at some point, you will have to ask: Are these really my best options?

If you’re ready to deal with the high costs, complexities, and sometimes mediocre performance of the commonly used systems, then you are free to choose any type of system. But if you really want an effective climate control solution for your basement that is capable of meeting all your cooling and heating challenges while giving you substantial energy savings, then, hands down, your best, smartest choice is a ductless mini split system.

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