800 square feet is not a massive space, but big enough that a single window unit probably won't cut it for keeping comfortable. Time to consider buying a mini-split system. But what mini split size do you need for an 800-square-foot area? Going too small means it won't have enough power. Too big is just wasting money upfront and on your energy bills. The good news is there's a sweet spot for 800 square feet. In this article by The Trade Table, we'll break down a few easy rules of thumb to figure out the proper mini-split BTU range and features for your 800-square-foot space.
GREE Livo Gen4 18K BTU 17.5 SEER2 Wall Mount Mini-Split Single Zone Heat Pump - 4LIV18HP230V1A
$1,710.55
GREE Livo Gen4 18K BTU 17.5 SEER2 Wall Mount Mini-Split Single Zone Heat Pump The 4LIV18HP230V1AH / 4LIV18HP230V1AO single-zone system is one of Gree’s new 3rd generation of Livo mini splits designed to provide a convenient, efficient method to cool… read more
How to Determine the Right Mini Split Size for 800 Sq Ft
The most important factor in determining the proper mini-split size is the square footage of the space. As a general rule of thumb, you'll want a unit that can handle 20 BTUs (British Thermal Units) per square foot for cooling and 25 BTUs per square foot for heating. For an 800-square-foot area, that works out to around 16,000 BTUs for cooling and 20,000 BTUs for heating.
However, square footage alone does not account for other factors like ceiling height, insulation, windows, and occupancy. Rooms with high ceilings, lots of windows, or poor insulation will require a higher BTU unit. Likewise, spaces that will have more people in them at once need increased heating and cooling capacity. It’s best to consider:
Ceiling height: Add 10% more BTUs for 9-foot ceilings and 15% for cathedral ceilings.
Windows: Add 10% more BTUs for many windows or large windows facing south or west.
Insulation: Add 15-20% more BTUs for poor insulation.
Occupancy: Add 10% more BTUs for 3-4 regular occupants, and 20% for 5-7 occupants.
MRCOOL E Star DIY 4th Gen 18k BTU Ductless Mini-Split Heat Pump Complete System - 208-230V/60Hz
$2,156.00
E Star DIY 4th Gen 18k BTU Ductless Mini-Split Heat Pump Complete System - 208-230V/60Hz The MrCool 4th Generation DIY 18K BTU, 22 SEER Ductless Heat Pump system offers a complete solution to your home’s heating and cooling needs. This… read more
Factors That Affect Mini Split Sizing for an 800 Sq Ft Space
When determining what size mini split is right for an 800-square-foot space, several factors come into play. The most important elements to consider are:
Room layout
Think about the layout and usage of the rooms in question. If it's one open-concept living area, a larger unit may be needed versus separate, closed-off rooms. Also, consider if there are any particularly drafty or poorly insulated areas. A more powerful unit can help ensure even cooling and heating throughout.
Ceiling height
The height of your ceilings plays a significant role in the size of the mini split required. Higher ceilings, especially those over 9 feet, mean more space for the conditioned air to circulate. As a result, a more robust unit with a higher BTU rating is usually needed for spaces with vaulted or cathedral ceilings.
Insulation
How well insulated your space is will directly impact the mini split sizing. If you have poor insulation, especially in the attic or walls, more of the cooled or heated air can escape. To counteract this and maintain a comfortable temperature, a unit with a higher BTU rating is typically required. Adding insulation can help improve efficiency and allow for a smaller mini-split.
Occupancy
The number of people regularly occupying the space is another factor to keep in mind. More people mean more body heat and a greater demand for cooling and heating. For an area frequently used by several people at once, such as a living room, size up to a more powerful mini split to ensure everyone's comfort.
Local climate
Your local climate plays an important role in mini-split sizing. Colder regions typically require a unit with a higher BTU rating to heat the space efficiently, while hotter climates usually need more cooling power. Check local HVAC guidelines and consider your area's average temperatures when determining the right size mini-split for an 800-square-foot space.
Buck Cool Mini-Split EZ Connect 18K BTU Complete Installation Kit
$2,534.42
$3,119.99
Buck Cool Mini-Split EZ Connect 18K BTU Complete Installation Kit The Buck Cool Mini-Split EZ Connect Complete Kits are designed to offer a simple solution for your heating and cooling needs. The pre-charged EZ Connect line sets allow for a… read more
Recommended BTU Output for a Mini Split in 800 Sq Ft
For an 800-square-foot space, you'll want a mini split with an output of at least 12,000 BTU to effectively heat and cool the area. Anything less won't have enough power and your room won't reach the temperature you want. On the other hand, too large of a unit, say over 28,000 BTU, will cycle on and off frequently, reducing efficiency and shortening the unit's lifespan.
Why BTU Matters
BTU stands for British Thermal Unit and measures the amount of energy needed to heat or cool a space. The higher the BTU rating, the larger the area a mini split can efficiently heat or cool. For an 800-square-foot room, aim for a mini split with 12,000 to 28,000 BTU to maintain a comfortable temperature without wasting energy.
Calculate the Right Size
To determine the precise BTU needs for your 800 square-foot space, consider factors like:
Ceiling height: Higher ceilings require more BTU.
Insulation: Well-insulated rooms need fewer BTUs. Poorly insulated rooms need more.
Windows: More or larger windows mean additional BTUs are needed.
Occupancy: Spaces with more people require higher BTU.
Equipment: Mini-splits also need to account for heat given off by appliances, electronics, and lighting.
Choosing the Right Number of Indoor Units for 800 Sq Ft
When cooling 800 square feet with a mini-split system, you'll need to determine how many indoor units to install for the most efficient and effective cooling. For a space this size, you'll typically want to go with either a single-zone or dual-zone mini split.
Single Zone
A single zone mini split with an appropriately sized outdoor unit (around 9,000 to 12,000 BTU) should work well for cooling 800 square feet. A single unit can effectively cool this size area. The main downside is the lack of control over the temperature in different rooms or sections of the space. But if you have an open floor plan or don't need precise control, a single-zone split AC would be a simple, affordable option.
Dual Zone
For more precise temperature control in an 800-square-foot space, a dual zone mini split system is a great choice. Two wall units, each controlling 400 square feet, will allow you to set different temperatures for separate areas like the kitchen/living room and bedrooms. An outdoor unit in the 12,000 to 18,000 BTU range would work for powering two indoor wall units in a space this size.
The dual zone system does cost more upfront but can save energy since you're only cooling areas you're using. It also provides more flexibility for different needs. For example, you may want it cooler in the bedroom for sleeping, but warmer in the living room during the day.
MRCOOL DIY Easy Pro® 18k BTU Ductless Mini-Split Heat Pump Complete System
$1,454.00
MrCool DIY Easy Pro® 18k BTU Ductless Mini-Split Heat Pump Complete System The MrCool DIY Easy Pro® 18k BTU Ductless Mini-Split Heat Pump Complete System is a high-performance heating and cooling solution for your home. It features an 18,000 BTU… read more
Ideal Mini Split Choice for 800 Sq Ft
For many of you, the math and specs on mini splits can be a bit overwhelming. But the key takeaway is that you want to focus on a unit with the right BTUs to properly cool your square footage and a higher SEER rating for efficiency. If you have an 800-square-foot space, a 12,000 BTU mini split with a SEER 15 or higher should do the trick nicely. And remember, a good contractor will help you determine the best size and placement of your indoor and outdoor units too. While there are a lot of details to consider, finding the right mini-split doesn't have to be complicated. With a little research and help from the pros, you'll have the perfect system for cooling your home in no time.
