A quick math lesson is all you'll need.
The square footage of your space is an essential piece of information to know. You need to know the square footage of a room's floors before you shop for new wood flooring, floor tiles, carpet, and more. Knowing a room's square footage will also make shopping for large furniture items much easier. The same is true for the area of your walls; before you make any purchases, you should measure your walls so you know exactly how much wallpaper or paint you'll need to cover them. In this guide, we'll show you how to find the square footage of a room's flooring and walls.
How to Find the Square Footage of a Surface
How to Use Your Calculations to Buy Flooring &
Wallpaper
Flooring Calculator
Walling Calculator
What You'll Need
- A tape measure
- A calculator
- A writing utensil and paper or a device for note-taking
Step 1: Measure the height and width of the floor or wall. If your floor or wall is square, rectangular, or triangular, measuring is a simple process. If your floor or wall is a complex shape, use the following diagrams to learn how to break it up into its simplest components. Then, measure the height and width of each component. Be sure to record your measurements so you don't have to repeat this step!
Step 2: Use those measurements to calculate the area of that shape. Locate your shape on the following reference sheet to see what formula you should use to calculate its area. If you calculated the areas of multiple shapes, be sure to add their areas together to find the square footage of the entire space. And that's all there is to it!
How to Use Your Calculations to Buy Flooring & Wallpaper
Once you know the square footage of your room or the area of your room's walls, you're almost ready to shop. Using the exact calculations you found to purchase flooring or wallpaper most likely won't leave you with enough material, especially if your floors or walls are irregular shapes. It also won't allow you any excess in case you make a mistake. If you're in the market for patterned wallpaper, you'll also need to allow yourself excess for pattern matching. In this section, we'll help you determine how much flooring or wallpaper to buy using the square footage or area you calculated earlier.
Most of the following guidelines ask that you add a certain percentage of your square footage to the total amount of flooring or wallpaper you buy to allow for excess. We've laid out the steps below.
Step 1: Convert the waste percentage to its corresponding decimal. The waste percentage is the percentage of the total square footage that you need to add in order to account for waste and excess material. This is often 10%, but you can reference the waste percentage that is specific to your type of material or project in the "Flooring Calculator" section below. You can convert this percentage to a decimal by moving the decimal point two spaces to the left. For example, 10% would become 0.1 and 5% would become 0.05.
Step 2: Multiply your square footage by the decimal found in Step 1. The result of this calculation is the amount of excess you'll need to buy. If your answer is a decimal, round up to the nearest whole number.
Step 3: Add the result of that calculation to your total square footage. Here's an example of this whole process: A room is 250 sq. ft. and 10% is the recommended additional amount for waste and excess for our chosen flooring. 10% of 250 (or 250 x 0.1) is 25. Add 250 and 25 together, and we get 275 sq. ft., the recommended amount of flooring to purchase for this space.
Step 4: Calculate how many floor or wall tiles you'll need (Optional depending on product). If you're interested in purchasing floor or wall tiles that are described by their dimensions in inches (not feet), you'll need to do a bit more calculating to determine how many tiles you'll need to fill the space. First, find the area of the tile in square inches by multiplying its length by its width. Then, convert your floor or wall's square footage (with the waste percentage already added) into square inches by multiplying it by 12. Then, divide that number by the area of the tile you just found. Round up to the nearest whole number and voila! You've found the number of tiles you should purchase.
Flooring Calculator
Tip!
If you don't feel like doing the math, let us do it for you! If you shop for flooring on Wayfair, there's an option to automatically add a certain percentage for waste and reserve to your order. Click How to Calculate Area beside the square footage entry space for more information and options.
Carpet: Wayfair sells easy-to-install carpet tiles that are listed by their dimensions in inches.
Percentage for Waste & Reserve: Add 10% – 20% to your square footage to allow for entryways, errors, and seam matching. If you choose a
patterned carpet, stick closer to 20% to account for pattern matching.
Hardwood: Hardwood flooring is usually sold by the square foot, which should make your shopping experience a bit easier. These same guidelines apply to purchasing engineered hardwood and bamboo flooring.
Percentage for Waste & Reserve: Add 5% – 10% of excess to your square footage.
Vinyl: Available
in both planks and tiles, vinyl flooring can be sold by square foot or by tile. Many planks and tiles are listed by their dimensions in inches.
Percentage for Waste & Reserve: Add 5% – 15% to your square footage.
Laminate: Similarly to vinyl, laminate can be available for purchase by square foot or by plank or tile.
Percentage for Waste & Reserve: Add 5% – 15%. Because some laminate breaks
easily, especially if you're cutting it yourself, you might want to stick with the higher end of that range.
Tile: Tile flooring can be some of the most beautiful flooring around, but with more intricate designs comes the need for more excess. Like laminate and vinyl flooring, floor tiles are sold by square foot or by individual tile and are listed by their dimensions in inches.
Percentage for Waste & Reserve: Most
guidelines say you will be fine if you purchase 5% – 15% extra for simpler tile designs and patterns. With more intricate designs, you may need to purchase up to 30% more floor tile to account for pattern matching, broken tiles, mistakes, and general excess.
Walling Calculator
Wallpaper, wall tile, and wall paneling follow similar rules as flooring when it comes to purchasing excess.
Tip!
Wayfair also offers an automatic excess calculator for wall coverings! Simply check the box marked Add 10% for waste and reserve or click How to Calculate Area for more options.
Wallpaper: Wallpaper is typically sold in double rolls (two single rolls together), with each double roll being able to cover 56 – 64 sq. ft. and each single roll being able to cover 28 – 32 sq. ft. When calculating how many rolls you'll need to cover your wall, you should divide the area of the wall by the
square footage of the double roll, not the single roll. Wayfair sells wallpaper in single and double rolls, so be sure to check the dimensions of the product carefully before you buy. Wallpaper is often packaged in batches, meaning that paper from one batch won't look identical to paper from another batch. Having too much wallpaper leftover is a bonus – use it to decorate the insides of closets or drawers or paper over the sides of some furniture to give it a unique patterned look.
Percentage for Waste & Reserve: Adding 10% is a general rule, but with wallpaper you'll likely need to purchase an extra roll. It's always better to purchase a little extra – likely a roll or two – from the same batch, because it will better match the rest of the wallpaper.
Paneling: Wall paneling can be sold by square foot or by tile or plank. Tiles and planks are displayed by their dimensions in inches.
Percentage for Waste & Reserve: We recommend you add about 5% – 10% for waste and excess.
Tile: Wall tile is available in three main forms: standard wall tile, backsplash tile, and peel-and-stick tile. Standard wall tiles (including decorative accent tiles) are typically sold individually by tile dimensions (in inches or square feet). Backsplash tile is typically sold in sheets of smaller tiles that are already bonded
together, with each sheet described by its dimensions in inches or square feet. Peel-and-stick backsplash tile is typically sold either by 1 sq. ft. sheets or by sheets described by their dimensions in inches or square feet.
Percentage for Waste & Reserve: We recommend adding 10% – 20% to your wall's area to allow for excess – closer to 20% or more if you're using more intricate patterned tiles.