Updated at: 25-10-2022 - By: Sienna Lewis

How to construct a ledge for an A/C unit in a window. There are only eight easy steps and a few sturdy components needed to construct your window air conditioner support.

Air conditioners, on the other hand, are not optional additions to any modern home. Some of them cost a lot of money. In order to prevent their waste, they should be stored away for the time being.

Because half of the cooling system will be located outside the home, we prepared to accommodate window-mounted units. If it isn’t properly supported and instead leans on the skinny window sills, it could topple. But wait, there’s a lot more info regarding AC maintenance and repair that you need to know, so keep reading!

Why Is It Necessary To Build A Window Air Conditioner Support?

The process of installing a window AC unit is straightforward. However, more support will be needed in the event the unit weights more than a hundred pounds, as it is more topple-prone. Any kind of support or bracket will keep it from toppling over and harming the residents or causing structural damage to the house or the air conditioner.

Support from the building is essential for the air conditioner’s upkeep and durability, in addition to assuring its safety.

You can get an AC bracket at any home improvement store. However, not every air conditioner can be fitted with a suitable bracket. Your air conditioner can have a more adaptable support structure, making it easier to construct. Costs will be reduced as well due to the reduced quantity of materials required.

If you have a window air conditioner and are having trouble, read on. To begin, just stick to the basic guidelines we’ve provided.

A Step-by-Step Guide To Build A Window Air Conditioner Support

Have you been trying to figure out how you can maintain your window air conditioner? Don’t worry; I’ll show you how to construct a window air conditioner stand:

Step #1. Measure the window’s width

Measure the width of the window sill. Take a careful look at the groove in the window frame where the slides will fit, and make sure it’s deep enough and wide enough.

Step #2. Cut the lumber to the size of the window’s width

This process calls for a jigsaw and a two-by-four piece of lumber. Mark the window’s width with a pencil on the lumber. Follow the contour of the window to determine how wide of a piece of lumber you’ll need to cut with the jigsaw.

Step 3#. Copy the width of the channel on the lumber

In this step, you’ll put to use the equipment and wood you already cut. Use the four-inch side of the timber to trace the channel’s width. Yes, action is required on both sides. Make a pencil mark at each end to indicate the breadth. Usually, the width of a channel is about an inch and a half. Consequently, you’ll be more likely to mark off half an inch at both ends.

Step #4. Draw the channel depth on the four-inch face of the lumber

Make pencil markings along the top and bottom margins of the four-inch face of the timber to indicate the depth of the channel. Second, on the top and bottom margins of the channel, mark off a depth equal to half of the total. Before the borders, there should be two lines. To complete this stage, draw lines that are perpendicular to the ones you just made.

Step #5. Cut the corners

L-shaped marks in the corners will help immensely. The next time you need to save some time, just follow the arrows. When you’re done cutting, both ends will have notches that may be inserted into the channel of your window.

Step #6. Attach the lumber to the window frame

Use the side channels of the window to insert the notch. Do not block the lower half of the glass with the planks. Prepare for the installation of your air conditioner via window.

Step #7. Place the lumber and the upper lips of the AC against each other

If required, make alterations to the wood. If you put it directly over the AC unit, that would be ideal. Verify that the top lip of the air conditioner is resting on the wood.

Step #8. Drill holes and insert the screws

Use a drill to make holes in the wood through the AC’s lip at the top. The air conditioner’s support will be made more sturdy by screwing in the necessary anchors.

Ensure that the screw, ideally a wooden one, fits through both the hole in the board and the hole in the timber. Then, use a screwdriver to make it as tight as possible to ensure its durability.

Things You Should Remember In Building A Window Air Conditioner Support

Tip #1. Match the color of the frame to the lumber

Inconsistency in color between the air conditioner support and the window frame is immediately eye-catching as unattractive. Painting it the same color as the windows will help it blend in and not draw attention away from the rest of the house.

Tip #2. Choose the right window for your air conditioner

The window must be situated near a power source. Think about the window’s durability and where in the house it will be installed. Choose a centrally located window, for instance, and the cold air will be dispersed throughout the entire home.

Tip#3. Wear Protective Equipment

The sustaining structure was built through the use of cutting and drilling. Wear protective gear like gloves and goggles to keep from getting hurt.

The Dos and Don’ts of Installing a Window Air Conditioning Unit

DON’T assume you’re permitted to install a window unit.

If you don’t know whether or not you’re allowed to install a window air conditioner in your apartment, condo, or HOA-controlled neighborhood, you might want to call the management office or the HOA board and find out. Some buildings forbid window air conditioners because they are unsightly and pose a safety risk if put incorrectly.

DO assess your windows.

A/C units can’t be installed in just any old window. Most of these devices are made to fit a double-hung window, which has a stationary upper pane and a movable lower one. Both horizontally-moving casement windows and vertically-moving sliding windows are incompatible with these units.

Most window units have a chord that is no more than six feet long, so you’ll also need access to a three-pronged electrical outlet near the window. AC units mounted in windows should never have an extension cord attached to them. Many air conditioners’ warranties would be voided if they were used with an extension cord that wasn’t designed for that purpose, and it would also be a fire hazard.

Finally, the region immediately within and beyond the window should be taken into account for optimal performance. Air conditioners lose as much as 10 percent of their performance when exposed to direct, strong sunshine as they struggle to cool the room’s air. Keep in mind that the air conditioner needs 20 inches of clearance on all sides to ensure smooth airflow, so make sure that neither the window nor its surrounding furniture, bushes, walls, or other impediments will get in the way.

DON’T neglect to check your measurements.

Selecting the proper window air conditioner requires two sets of dimensions: the room’s square footage and the window’s height and width. Make that your measurements fall within the range indicated on the air conditioner’s box, which will typically include both the minimum and maximum window sizes that may accommodate the unit.

Open the window as far as it will go, and then measure its width and height to get its exact dimensions.

Have a helper hold the end of the tape measure against one wall as you extend it to the other side to get the length, and do the same to get the breadth if you don’t already know it. Then, multiply those two figures to get the area in square feet. If your room is 11 feet broad and 12 feet long, for instance, its square footage is 132.

DO choose appropriate power for your space.

The energy efficiency rating (EER) and the British thermal units (BTUs), a measurement of the appliance’s cooling ability, are also necessary for making the proper buy while looking for an air conditioner.

The greater the EER, the more energy-efficient the air conditioner is. When it comes to power savings and efficiency, the United States Department of Energy suggests going with an EER of 10 or above.

BTUs needed to cool a greater space. Because of this, if the air conditioner isn’t strong enough for the room, it will keep running without ever being cool enough. If it’s too strong, the air conditioner will turn on and off too frequently, leaving the room’s humidity unreasonably high for too long and causing temperature differences between different areas. For the most part, the BTU rating of a window unit will correspond with the manufacturer-recommended room size, but if you want to get a more precise estimate, you can use the BTU calculators provided here.

DON’T attempt installation without a helper.

Because of its size and weight (usually between 50 and 100 pounds), installing an air conditioner in a window requires at least one other person to help with the installation process. It’s easy to hurt yourself or damage the unit by trying to install a window air conditioner on your own.

DO prepare the window and install brackets, if necessary.

Open the window as far as it will go, take out the screen, and clean the sill, glass, and window frame before installing a window air conditioner. Mark the middle of the window sill with a pencil using the measured width.

A well-installed air conditioner shouldn’t need a bracket to stay in place in the window. There is a need for extra support for air conditioners that weigh more than 100 pounds, and in some places, like New York City, a bracket is required for all window units. Support brackets are often sold separately. You can find window unit brackets at any hardware store or online. Price range for a mounting bracket is $30-$100.

Air conditioner brackets come in a variety of shapes and sizes, but the most common ones look like a little shelf or a pair of “legs” that extend just outside the window to secure the unit. Support brackets for window units, like the Ivation Window Air Conditioner Support Bracket (sold on Amazon), have come a long way in recent years, with many models eliminating the need for drilling or screws to secure the unit to the window. The Ivation includes two rubber-tipped “feet” that rest against the external wall and an extendable bar that fits securely in the lower window frame.

DO attach mounting rails and side panels.

The top and bottom mounting rails that help keep the air conditioner in place in the window are included with some window units. If your device doesn’t come with mounting rails, you may easily install them by using the screws that came with it and then tightening them to the specified amount.

Once that is done, slide the accordion-style side panels into the grooves on either side of the AC and snap them into place. Panels will be installed to cover the space between the air conditioner and the window frame.

With the aid of your helper, lift the window unit and position it on the windowsill once the mounting rails and side panels have been installed. The air conditioner may be securely fastened into place by fitting the bottom mounting rail into the lower window frame. Place the center of the air conditioner directly in the middle of the window, where you previously put a mark. Now, with the help of your assistance, lower the open window sash until it rests atop the air conditioner, with the top mounting rail of the air conditioner aligned with the lower edge of the sash. This provides an additional layer of security for the window unit.

DON’T forget to measure the unit’s tilt.

Condensation from air conditioners and heaters might drip down the wall inside your home if the window isn’t slightly tilted away from the building. The manufacturer may specify a different amount of tilt, but half an inch is a good rule of thumb. The manufacturer may have already fitted the drip pan at an angle in certain newer models, eliminating the need for a tilt.

DO install the L-brackets and foam window gasket.

Your helper should maintain the window air conditioner steady as you use a power screwdriver or drill to fasten the L-brackets, which are the letter L-shaped parts that act as the final safety safeguard to keep the air conditioner securely in place. Each L-bracket is secured to the side of the window frame, and one end screws into the lower edge of the sash of the sliding window. Preventing the window from opening, which could result in the unit falling out, is an important safety feature. Your air conditioner may come with either one or two L-brackets, depending on the brand.

There will be space between the panes of glass once the upper one is fastened. Use the foam seal that comes with the unit to fill in that space. If the seal doesn’t quite fit your window, you can trim it down and squeeze it into place. This helps to prevent the entry of cold air from outside. If you don’t use the foam seal around your windows, air leaks in and your window unit has to work harder to keep the house at a comfortable temperature.

DON’T leave side flaps unsecured.

The last step is to extend the air conditioner’s accordion side panels until they contact the window frame on both sides. Attach the side panels to the window frame with the screws provided by your air conditioner, using a power screwdriver or drill.

Congratulations! The installation of your new window air conditioner has been completed. Just plug it in, switch it on, and feel the sweltering heat of summer melt away.


Do all window air conditioners need a support bracket?

A well-installed air conditioner shouldn’t need a bracket to stay in place in the window. Some places, most notably New York City, mandate the use of a bracket for all window air conditioners regardless of weight, while others only demand its use for extremely heavy units (those weighing more than 100 pounds).

Should a window air conditioner be tilted?

Air conditioners installed in windows remove warm air and humidity from a room and replace it with cool air. Condensation can drain off of them if they are set at a little incline at the back.

Can you put a window air conditioner through the wall?

Overheating is common if a window air conditioner vents out the side, as this is where the vents are typically located. Only air conditioner models with a slide-out chassis wall sleeve can be placed through a wall.

What size window air conditioner do I need?

Make sure the window air conditioner you choose is the right size for your space by measuring its dimensions before placing your order. If the equipment is not properly proportioned, condensation may form in the crevices, and the room will not be cooled effectively. This will obviously result in increased energy costs as the appliance will run longer than necessary.

The Home Air Quality industry uses the British Thermal Unit (BTU) to compare the heating and cooling capacities of various appliances. In areas as large as 250 square feet. feet, you need air conditioners with 7,000-8,000 BTUs to keep things cool. Rooms between 300 and 425 square feet are available, nevertheless. cooling capacity of around 10,000 BTUs to 12,000 BTUs would be ideal for a space of this size. Guests can choose from rooms that are between 425 and 525 square feet in size. cooling capacity of about 14,000 BTUs from a window air conditioner would be about right for a 600 sq.

For a more precise estimate of the BTU range required to maintain the target room temperature, the following chart can be of assistance. Check out this post for a more in-depth breakdown of how to choose the ideal air conditioner size for your home.

Where should I install my window air conditioner?

Several considerations must be made before settling on a spot for your window air conditioner. Make sure you select the correct window air conditioner by taking into account the room’s purpose, ceiling height, number of doors and windows, amount of sunlight, and amount of foot traffic.

Optimal performance from an appliance requires accounting for these factors, as recommended by Energy Star. Reduce the BTU capacity by 10% if the room is substantially shadowed and doesn’t get as much sunlight. Alternately, if the space receives a great deal of natural light, the BTU output should be increased by 10%. If more than two people are frequently using the space, the capacity should be raised by 600 BTU per person. It is recommended that 4,000 BTUs be added to kitchens for optimal use.

It is especially crucial that the unit has the characteristics necessary to effectively direct and cycle air around the space if it is going to be installed in a corner.

There are two easy methods that can be used to determine the square footage of the room into which the window air conditioning unit will be installed. Multiply the room’s length by its breadth to get the square footage if the room is rectangular or square. A room’s size can be calculated by multiplying its length by its breadth and then dividing that number by 2.

What are the benefits of a window air conditioner?

When you choose and install the best window air conditioner for your home, you can enjoy its many advantages, including reduced energy costs and increased comfort. Cooling a room requires a unit with the right BTU capacity to cycle the air and keep it at a constant temperature. Buying a unit with a BTU capacity that is significantly higher than what is advised will cause the unit to turn on and off more frequently, which can increase the need for maintenance and shorten the unit’s useful life. Air distribution will be erratic and uneven with larger units, whereas it will be consistent and long-lasting with smaller ones.

More effective dehumidification can be achieved with window air conditioners of the right size and capacity. In order for condensation to occur for water to drain out of the unit, the cycle duration must be somewhat long. If you set up a system with more BTUs than you need, it will cycle less often and produce less condensation.

Installing a system with the appropriate BTU capacity also helps to lessen the unit’s impact on ambient noise. Since the fan motor and compressor will be smaller, the appliance will be able to run at lower speeds for longer without becoming too noisy, and this will be especially helpful at system starting.

Can I install the window air conditioner myself?

Sure, it’s easy to set up a window AC, which means you’ll save cash and get cool air faster. It doesn’t take long to install a window air conditioner if you’ve already determined where it will go and made sure it’s the right size. If you want to install a window, you need make sure there is nothing in the way of the opening.

Install brackets may be included with your window air conditioner; for instructions on how to use them, consult the owner’s manual.

After the mounting brackets have been put up, you can move the device to wherever you like. To find out where and at what angle you should put your air conditioner, consult the instructions that came with your unit (required angled placement helps units with condensation drainage). Afterward, fasten the accordion panels to the window’s lower sash. If the accordion panels have never been drilled before, refer to the owner’s manual for guidance on the size and orientation of the holes.

After ensuring that air can flow freely between the panes of glass, you should seal the gap with foam weather stripping to keep the elements out. This is included with the setup package, but you can also get it at any hardware shop. Sealing the exterior of your windows will protect them from the elements and keep away pests. It is also true that caulking can assist keep cool air from escaping through cracks and openings.

How do I clean and maintain the air conditioner?

A window air conditioner is simple and quick to maintain. Consistent upkeep is the key to extending the life of the unit and keeping it functioning as intended. Always make sure the appliance is unplugged before attempting any form of maintenance on it.

Maintaining a comfortable home environment relies heavily on keeping the air filter clean. There are both reusable and disposable filters for window air conditioners. If you want to know how to clean or replace something in your machine, the handbook should be your first stop. To begin cleaning a reusable filter, just wash it in warm water with a drop or two of dish soap or vinegar. It’s important to let the filter dry before reinstalling it in the AC. In general, it’s preferable to clean reusable filters once a month, but more frequent cleaning may be necessary if there are people in the home with allergies or dogs. If your appliance has a filter that can be swapped out, you should do it at least once every two months.

It’s important to keep the condenser coils clean to keep the unit running efficiently and to prevent residue and other filth from accumulating there. When an AC unit has to work harder than it should to keep you cool, it might increase your electricity bill and potentially decrease its lifespan if you don’t do something about it. Maintaining the coils is easy; just use a vacuum with a brush attachment and go over them once every few months. The device needs to be taken apart from its housing and cleaned thoroughly in open air. After rinsing the coils, a natural cleaning should be used. As a last step, wash the cleaner and let it dry completely before reusing.

Can I leave a window air conditioner unit installed during the winter?

Refer to the user guide for your window air conditioner to determine if it is winter-ready. If you want to make sure the device can withstand the weather, it is best to follow the manufacturer’s guidelines.

It is necessary to take precautions against moisture entering the air conditioning unit when not in use, therefore make sure to cover it with something watertight before putting it away. It is crucial to shield the window air conditioner from damage while making sure that airflow is not obstructed if the machine has heating capabilities.

Will Energy Star rated models save money?

There is some truth to the claim that Energy Star-certified window air conditioners can cut down on your monthly energy bills by as much as 30 percent. Having an Energy Star rated window unit will help you save money, while the exact amount will depend on a number of factors.

Energy Star is a rating system for energy-efficient appliances that was created in 1992 by the United States Environmental Protection Agency. Obtaining an Energy Star rating requires meeting rigorous standards for energy efficiency.


Your air conditioner is less likely to break or go to waste if it is properly anchored. Since we have made a financial investment, we need to treat it with the same degree of care we do with our other household gadgets.

Learning how to construct your own window air conditioner support is a great way to cut costs. But before you start, make sure you have everything you need and that you know what to do to make the support sturdy and long-lasting.

The topic of “how to create a window air conditioner support?” has been concluded. I pray this text was enlightening to you. To learn more about sustaining an air conditioner, check out our article on constructing a suitable bracket for the device.