How To Measure for Carpet Replacement (2024 Guide)

Measuring carpet is an easy DIY job. Learn how in our step-by-step guide.

Written by Angela Bunt Updated 04/18/2024

Installing new carpet is an exciting way to refresh your home’s look. Before diving into the project, you will need to measure your living space to ensure you get enough carpet for the job. Our guide details how to correctly measure your home for carpet installation.

Before You Start

We recommend having a piece of paper and pencil on hand to keep track of your measurements. Start by sketching your home’s layout. If you only want carpet in one room, sketch that area. If you’re installing carpet in multiple rooms, sketch every room. Make sure to include any interior spaces, such as closets or pantries.

The floor plan sketch doesn’t have to be exact as long as it roughly matches your home’s proportions. Record your measurements on the layout as you go.

Tools and Equipment

Below are the tools and equipment you need for carpet measuring:

Calculator

Paper

Pencil

Tape measure

How To Measure for Carpet

Measuring a room to install carpet is simply measuring the length and width of a room, then multiplying them together to get the room’s square footage. Follow the below steps to measure correctly for carpet installation.

1. Measure the Length and Width of the Room

Start by deciding which side of your home is the length and which is the width. Add these labels to each wall on your sketch. Then, measure the length and width of each room you’re installing carpet in.

Keep your sketch of the home’s layout nearby while using a measuring tape to measure the length and width of the room or rooms where you’re installing carpet. If there’s a doorway on one wall, measure to the center of the doorway instead of the wall to account for the extra two to three inches. Write down the measurements on your sketch for future reference.

2. Measure Any Interior Spaces

If the rooms you’re installing carpet in have closets or pantries where you’ll also want carpet, measure them next. Keep these measurements separate from your primary measurements. Remember to measure to the center of the doorway instead of to the wall.

QUICK Tip

If the area you’re measuring includes stairs, measure around the nosing, which is the rounded edge of a step. Wrap the tape measure around the nosing until it touches the back of the riser— the vertical space between one step and another—of the stair below.

3. Make Split Measurements for Oddly Shaped Rooms

We recommend splitting up oddly shaped rooms—such as rooms with corners, doors, windows, and recesses—into easy-to-measure sections and labeling the different parts. For example, you might break down an L-shaped room into two separate parts, then measure each part’s length and width. Another example would be measuring the maximum length and width of the triangular corner of a room.

For any curved walls, measure the radius by recording the distance across the front of the wall, making a straight line from one side to the other. Then, measure the wall’s depth from the top of the curved arc to the front edge of the straight line you made.

4. Calculate the Total Area

Now, calculate the total room size. You can use various calculations depending on the room. For any square or rectangular spaces, use length x width = area. For any triangular spaces, use (length x width) / 2 = area.

If you need the area of a curved or rounded portion of the room, measure the radius of the curve and follow the formula below. This equation is more complex than the others, so we’ve listed multiple steps. If this formula below is too complicated, you can use this helpful arc calculator, which only requires the width and height.

Divide the curve depth by two.
Square the curve width.
Multiply the curve depth by eight.
Divide the result from Step 2 by the result from Step 3.
Add the answer from Step 1 to the result from Step 4 to find the radius.
Square the radius.
Multiply the squared radius from Step 6 by π (3.14).
Divide the result from Step 7 by 2 to find the total area.

5. Calculate the Total Square Footage

To find the square footage of square or rectangular rooms without interior spaces, multiply the length measurement in feet by the width measurement in feet. This will show you the area in square feet.

If the room is oddly shaped or has interior spaces, add the area of each part of the room to find its total square footage. For example, add the area of a large closet to the area of the room itself to get that room’s total square footage. This is the amount of carpet you’ll need for that room. We suggest rounding up to the nearest foot if the number isn’t already rounded.

QUICK Tip

Add each room’s total together to get the total square footage of carpet you need. Multiply this number by 0.1 and add that result to the total square footage. This adds 10% to the total, ensuring you buy enough carpet to get the job done.

Our Conclusion

Measuring your home to prep for new carpet is an easy step homeowners can do on their own. Many homeowners also find that carpet installation is a home improvement project they can handle themselves. We don’t recommend carpet installation for do-it-yourself (DIY) beginners, so consider hiring a pro if you feel uneasy about the project.

Retailers such as LL Flooring and Empire Today offer massive carpet catalogs, professional installation services, and reliable warranties. Click below to schedule consultations with flooring technicians that service your home’s address.

FAQ About How To Measure for Carpet

How much extra should I allow when measuring for carpet?

Rather than adding a certain amount to each measurement, we recommend multiplying your total square footage by 0.1, then adding that number to your total. This should give you 10% extra carpet to work with if any problems arise.

Does carpet make a room look bigger or smaller?

Wall-to-wall carpeting is known to make a room seem bigger. This is because the carpet’s continuity gives the appearance of more space.

How much carpet do I need for a 12×12 room?

If the 12 foot by 12 foot room in question is a simple square, multiply those two measurements to equal 144. Therefore, you need at least 144 square feet of carpet. We recommend adding 10% to the total—or multiplying 144 by 0.1 to get 14.1 and then adding that to 144 to get 158.4.

How does carpet compare to vinyl flooring?

Carpet is popular in living rooms nationwide because it’s affordable, reduces noise, and has numerous design options, such as patterned carpets. Luxury vinyl flooring offers more long-term durability and mimics the appearance of other flooring types, such as wood or stone.

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Flooring options (24 points): We browse each provider’s catalog to learn which flooring options it provides, checking for wood, engineered wood, tile, laminate, vinyl, carpet, concrete, or linoleum. The more options available, the higher the score.
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