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How Many BTU for 400 Square Feet
400 square feet needs about 10,000 BTU/h to cool and 14,000 BTU/h to heat a standard insulated room. A 10,000 BTU window unit fits.
How Many BTU for 400 Square Feet
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About How Many BTU for 400 Square Feet
For 400 square feet of standard insulated room, cooling needs about 10,000 BTU/h, using 25 BTU/h per square foot. That is a room of roughly 20 by 20 feet, the size of a large living room or a small open plan studio, and 10,000 BTU is one of the most common window and portable unit sizes. This page loads with 400 square feet already entered so you can see the base figure and then adjust for the space. A portable unit rated at 10,000 BTU will usually struggle to deliver that in practice, because the exhaust hose and the air it pulls in through gaps around the door both work against it. If you are choosing a portable, size up to 12,000 or 14,000 BTU, or consider a window unit or a small mini-split instead. Ceiling height matters as well: the rule assumes 8 feet, and a 10 foot ceiling pushes the figure to about 10,500. For heating, 400 square feet needs around 14,000 BTU/h, about 4 kilowatts, which a mid-size heater or a heat pump handles. For the next size up see How Many BTU for 500 Square Feet, and for a smaller room How Many BTU for 300 Square Feet.
How to use How Many BTU for 400 Square Feet
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Frequently Asked Questions
How many BTU do I need for 400 square feet?
About 10,000 BTU/h for cooling a standard insulated room. A sunny room or one with a higher ceiling needs more, and a bedroom about 8,000.
Will a 10,000 BTU portable AC cool 400 square feet?
Often not as well as the rating suggests. Portable units lose capacity through the exhaust hose and through warm air drawn in to replace what they expel. Size up to 12,000 to 14,000 BTU for a portable.
Is a window unit better than a portable for 400 square feet?
Usually. A window unit keeps the hot parts outside, so it delivers closer to its rated capacity and runs more quietly in the room.
How many BTU to heat 400 square feet?
About 14,000 BTU/h for a standard insulated room, roughly 4 kilowatts. A mid-size heater or a heat pump is the usual choice.
What size room is 400 square feet?
About 20 by 20 feet, the size of a large living room, a two car garage or a small studio apartment.