How Much Extra Flooring to Buy

A worker installing hardwood floor
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Floor manufacturers typically recommend that consumers purchase more flooring materials than is necessary. If you happen to be new to remodeling, this might come as a mild shock. Few other materials around the home need to be purchased in excess. If you need ten windows, you buy ten windows. Three doors require three doorknobs. Even with paint, it's best to finely tune the amount you purchase so that most of it ends up on your walls, not languishing in your shed for years.

Floor materials, though, work a bit differently. It is nearly impossible to purchase the exact amount of materials for the space on a perfect one-for-one basis. Expected wastage, defective materials, and installers' patience, motivation, and skill level are the main factors that control your flooring materials excess purchase. On top of that, not all flooring materials need to be purchased at the same levels of excess. Hardwood, for example, will be different than luxury vinyl tile or plank. Finally, the intended installation space will increase or lower the number of excess materials that you need to buy.

Expected Flooring Installation Wastage

Wastage never sounds like a good thing. But as it pertains to flooring installation, it is normal and expected. Wastage is a term that refers to the cut or otherwise discarded sections of flooring that do not belong in the floored space and which cannot be reused. Flooring manufacturers typically set wastage figure at between 5-percent and 15-percent.

Nearly all flooring installation requires cutting. The most common reason to cut flooring is because, during installation, a row of flooring materials has reached a wall. Using hardwood flooring as an example, an additional plank is brought out and cut to size so that it fills the gap (with a small expansion gap added). The remainder of that plank is retained and hopefully will be used in subsequent rows. Plank remainders that are too short or otherwise unsuitable for installation become wastage.

Large plank and tile-style flooring materials have the greatest wastage numbers. With some small-format flooring materials, particularly 1-inch mosaic tiles, wastage numbers may be on the lower end since the flooring sometimes matches the space without the need for cutting.

Rooms with a great number of obstructions drive wastage numbers higher, too. Toilets, cabinets, and vents are examples of obstructions that the flooring must work around.

Rooms that are square or rectangular account for lower wastage numbers than rooms that are curved or which have extra alcoves or niches. Installing hardwood flooring on a diagonal, while not common, wastes even more materials.

Defective Flooring Materials

For solid hardwood flooring, expect that as much as 5-percent of the material may be defective. Some of this defective material may be used, while some may need to be discarded.

Generally, when you buy a home-related product, you expect it to be in perfect condition. It would be unthinkable to purchase eight recessed lights when you only need five, with those excess three lights going straight to the trash when the project is complete. Yet a condition similar to that exists when it comes to some types of flooring materials.

Hardwood flooring can sometimes be defective. It may be missing tongues or grooves, or it might be water-stained, cracked or split, sun-discolored, or affected by a myriad of other imperfections. As an example, Lumber Liquidators' house brand Bellawood notes that up to 5-percent of its product may be unsuitable for installation.

This does not mean that all of it must be discarded. Most hardwood flooring installers are experts at working with imperfect material. While they do prefer to work with clean material, they know how to mitigate many of imperfections. Hardwood flooring lacking tongues or grooves can be face-nailed at the end of a room. Cracked flooring can be cut off prior to the crack.

Engineered wood flooring will have far fewer imperfections than solid hardwood. Ceramic and porcelain tile will sometimes come with a few tiles broken. Resilient flooring should always arrive in perfect condition.

Flooring Installers' Time and Skill Level

The inclination of the installer to be as economical as possible also drives wastage figures. Installing a floor is similar to piecing together a puzzle. Skilled, patient flooring installers can dramatically reduce the amount of waste materials. Others may cut off the end boards with little thought as to whether they could have found a better solution.

As a do-it-yourself floor installer who is also the purchaser of the materials, you will likely be motivated to reduce waste as much as possible.

How Much Extra Flooring to Order?

Luxury Vinyl Plank, Laminate, and Tile

Purchase between 5-percent and 10-percent extra flooring.

Hardwood Flooring

Buy the amount of flooring needed (100-percent), plus another 20-percent, maximum. This number is comprised of the 100-percent of flooring needed to cover the area, plus as much as 15-percent to account for installation wastage and 5-percent to account for defective materials.

Example, for a 15-feet by 30-feet square foot room, the total area is 450 square feet. Calculate total as such:

How Much Extra Hardwood Flooring to Order
Percentage Needed (%) Square Footage Description
100 450 Floor area itself
5 to 15 67-1/2 (using 15-percent calculation) Installation wastage
5 22-1/2 Defective materials
120 (maximum) 540 Total square feet of flooring to buy

Tips for Determining Flooring Quantities

  • If you are installing your hardwood flooring yourself and consider yourself an expert, reduce excess numbers to the lower end of the range.
  • If you are hiring flooring installers, go for a higher excess amount. You never want hired flooring installers to stop work early due to lack of materials.
  • If you bought the flooring locally and feel confident about that store's return policy, you may want to order excess boxes since you can take unopened boxes back to the store for a full refund.
  • If you bought the flooring online and returning the materials entails extra shipping costs that you will have to cover, keep the excess figures to a minimum.