With so much premium placed on spaces, attic conversion took off as a home remodeling fad. But as has long been attested by many homeowners, the most recognizable challenges that hinder the full maximization of this space is air conditioning. Whilst before an attic is mostly used as a convenient storage area, it has now taken new significance in the light of importance placed on having an extra space home that can be utilized for any type of room addition. Essentially, the change in lifestyle and the rising value of an additional household space in real property and home improvement markets has quickly nudged the transformation of attic into a valuable commodity and an essential source of space for any type of square footage expansion. And so, whether you’re remodeling or renovating the house, attic conversion will be worth the try and expense.

The truth is, an attic that’s perfectly transformed into a new livable space might just be what you need to have a new room that is dedicated for your hobbies, work, or relaxation. But as what’s usually true with any home improvement projects, factors such as convenience and comfort have to be considered. While architecturally there’s a usual focus on elements such as the structure, physical conditions, and limitations of the space, it is highly acknowledged that alongside safety and functionality, the climatic considerations and thermal comfort bear weight in any decision.

In the case of attic conversion, ensuring temperature comfort has an extra significance due to the characteristics of the space itself. Prior to renovation, keep in mind that an attic absorbs more heat than any other room inside your house. Being just below the main roof and typically designed and constructed as a rafter support, attic is a unique space that mainly serves a structural purpose. Most attics are usually vented, but if you’re looking to use this space as a new, livable area, your biggest consideration should be air conditioning. Take note that it’s only through proper air conditioning that you can truly achieve temperature comfort in this type of space. With air conditioning as a primary requirement, it follows that one of your main tasks is finding the right AC solution for an attic environment.

To help you decide on the best cooling solution for your converted attic, listed and discussed below are your possible options—from the workable to the smartest choice.

Room Air Conditioner A self-contained unit designed for single-room cooling, room air conditioners are probably the most widely used AC unit. Room ACs are either window air conditioner or through-the-wall air conditioner. The window air conditioner is usually installed on a standard-sized window with bracket acting as a weight support. The through-the-wall air conditioner, on the other hand, is typically installed through a wall opening and recessed through a wall-frame with chassis sleeve that also acts as a weight support.

• Why it’s a workable option? A room air conditioner in an attic is practically the easiest choice. It is low-cost, easy to purchase, simple to install, and you don’t really need anything except a window or a wall outlet where the unit will be placed and secured. If you have a little knowhow in HVAC installation and maybe a set of a basic tool kit, you can actually do the work on your own. In terms of application, a room AC is totally suited for a relatively small space such as an attic.
• Why it’s not exactly your best choice? Despite the room AC being purposely designed for single-room cooling, it has associated issues that make the system limited in terms of performance and efficiency. For one, most traditional room air conditioners are not capable enough to handle the extreme heat that’s normally present in an attic. This is true even if you have covered all the bases, including correct unit sizing and proper insulation. Ineffective cooling in a small, tight space like an attic is not always caused by a low-performing system but the characteristics of the space itself. At times, the structural challenges present in the application also compound the problem. Being a space located just beneath the roof and originally designed with no significant amount of ventilation, an attic is a natural magnet for heat build-up. When you consider the fact that the heat also rises up from inside the house, then what you get is a space that can get really hot anytime of the day. In fact, most of the time, the temperature inside an attic is even hotter than the outside climate. With that said, a room air conditioner with just a nominal or average cooling capacity, even if rightly sized, will be forced to work harder. Another limitation of a room air conditioner in an attic application is the size and physical appearance of the unit. Remember that room air conditioners are bulky and maximization of space is what brought you to the attic retrofit and renovation project in the first place. Aesthetically and practically speaking, a bulky AC system in a small space like an attic is not only ugly and obtrusive, but will also take up a space and even a sizable amount of elbow room. In terms of energy-use, room air conditioners are not known for efficiency as well. They consume to much energy. Installing them in a space such as a poorly insulated attic where energy losses is very possible would be very costly for you in the long run. Comfort-wise, room air conditioners are not also known as good humidifiers. And this says a lot about the comfort level that you can expect from this system considering that an attic is one of those spaces at home where the humidity level is normally very high.

Portable Air Conditioner Also a self-contained unit, a portable air conditioner is a type of single-room cooling system that is usually wheeled. That’s why you can easily move it around and place in the floor anywhere inside the room. Typically, a portable cooling unit works by exhausting the warm air and moisture inside the room. The window kit and the drain hose that come with the unit are used to remove the moisture that develops from air exhaustion. The condensate water that is collected from this moisture also goes through a removable container, which you can easily empty out when it becomes full. Some portable AC models can be vented by setting up the window kit and the exhaust hose through a wall or drop ceiling. This enables the system to bring the exhaust warm outside the room.

• Why it’s a workable option? A portable AC may be a little bit more expensive than many of the average room ACs, but it is definitely a cheaper option than ducted systems. A portable cooling system is very easy to set up as well. It does not require any type of complex installation or even a simple mounting procedure. For a small area like an attic, a portable AC might work effectively because it is mainly designed for spot cooling. When we say spot cooling, it means that the system is used to cool a targeted space directly which is almost similar to how you use an electric fan. Basically, you set it up facing the area where you need the cool air to be fully concentrated. In other words, you can move it anywhere and direct the air in any direction. This portability allows you to stay cool wherever you are inside the room. Even if you have medium-sized attic and you chose a vented portable AC, you would not have any problem at all in terms of the length of the hose because you can always extend it at any length necessary.
• Why it’s not exactly your best choice? Despite the flexibility that a portable cooling system provides, it is severely lacking in terms of the main requirements that most people are usually looking for in an AC system—most especially when used in a unique space like an attic that poses several inherent cooling challenges. At the very least, the drawbacks of a portable AC go against the main aims to ensure reliability and consistent level of temperature comfort. The reason for this is the system’s relatively low capacity in terms of cooling. No doubt that a portable AC is one of those ideal supplementary systems to larger HVAC units at home, but you cannot really expect too much from this solution unless you’re using some of the really advanced units. In an attic environment where the heat can get really serious and extreme, you might need to look for other systems with more powerful cooling capability.

Your Best Option: Ductless Mini Split System Designed both for single-room and multi-room cooling and heating, ductless mini split system is easily your best option if you are really looking for something that will enable you to enjoy consistent temperature comfort inside your renovated attic. A ductless mini split system is a compact unit that consists of an outdoor compressor unit and one or more indoor air handlers. For a single room cooling such as an attic application, all you need is 1:1 mini split configuration. This means one outdoor unit matched with one indoor unit. Not requiring ducts, a mini split system can be easily installed. All you need to do is mount the indoor unit inside the attic while the connected outdoor compressor unit sits outside the house. These two units are linked together as a single system by the refrigerant lines, power cable, and condensate drain line which are passed through a small hole in the wall.

• Why it’s your best option? To answer this question, it is important to emphasize that a ductless mini split system was specifically designed as an innovative alternative to traditional systems, such as a window air conditioner. The envisioned goal is to provide a system that is completely capable of working around the unique air conditioning challenges that conventional systems normally encounter. These may range from energy losses and installation limitations that are associated with ductwork to temperature fluctuations. Lack of control over the temperature is also often a compelling reason why mini split is being considered as the better alternative to traditional cooling systems.

As previously stated, an attic can be very hot inside especially during summer or too cold in winter. With average, conventional cooling systems, these might pose a serious problem. But with mini split system, you can have a year-round AC solution that is capable of handling extreme heat and even sub-zero temperature. In terms of saving space, mini splits are highly unobtrusive. The air handlers can be installed anywhere inside the attic regardless of your aesthetic considerations. Mini splits cost relatively higher than other systems, but they are mostly energy-efficient. Compared with traditional AC's, you can actually cut your energy cost with a mini split unit.  Generally speaking, ductless mini split gives you more benefits in terms of air conditioning a unique space like an attic, whether in terms of comfort, convenience, cost-savings, and flexibility.