To measure air ducts correctly, you need to determine the size of the duct opening itself, not the outer dimensions of any existing vent cover. Here's a step-by-step guide:
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Remove the Vent Cover: Carefully unscrew and remove the existing vent cover from the air duct. This will expose the duct opening.
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Measure the Width: Using a measuring tape, measure the width of the duct opening. Ensure you are measuring from edge to edge inside the duct.
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Measure the Height: Measure the height of the duct opening, again from edge to edge inside the duct.
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Record the Measurements: Note down the width and height measurements you've taken. This is the size you'll use when ordering a replacement vent cover or determining the duct's dimensions. For example, if the width is 18 inches and the height is 6 inches, you would record it as 18" x 6".
Example:
Let's say after removing the vent cover, you measure the duct opening and find it to be 12 inches wide and 8 inches high. This means you have a 12" x 8" air duct opening. When replacing the vent, you would typically order a vent cover sized for a 12x8 duct.
Important Considerations:
- Accuracy is Key: Be as precise as possible when measuring to ensure a proper fit for your vent cover.
- Inches are Standard: Air duct sizes are almost always expressed in inches.
- Duct Shape: While this guide focuses on rectangular ducts, the same principle of measuring the interior opening applies to other shapes (e.g., round, oval), although the specific measurements required will vary. For a round duct, you'd measure the diameter.
