How Much Extra Flooring to Buy

Floor manufacturers typically recommend that you buy more flooring material than is apparently necessary—at least, based on the space to be floored. Sometimes, that number ranges as high as 20-percent. So, a site that is 200 square feet may require as much as 240 square feet of flooring.

Few other building materials need to be purchased in such excess. When you buy five windows, you only buy five windows—not a few extra just for good measure. This is not a ploy by flooring manufacturers to encourage you to buy more flooring. Instead, buying extra flooring materials is a normal, expected part of installing flooring. You'll need to do this for nearly every type of flooring—sheet and roll goods, plank flooring, and tiles. Ordering an extra box or two is also beneficial for any possible future renovations or repairs, if needed.

Why Extra Flooring Is an Expected Purchase

Since floor spaces and flooring materials usually do not exactly match, extra flooring must be purchased. Sixteen-inch ceramic tiles in a space that is 52-inches wide will never fit exactly. An extra row of tiles must be purchased or cut tiles from another part of the flooring can be used, as well. Large rolls of 12- or 15-feet wide carpeting are routinely cut and seamed together since rooms rarely are exactly 12 feet or 15 feet wide.

Defective materials also determine how much extra material to buy. The more natural the flooring product, the more defects you can expect. Solid hardwood will always have more defective pieces than synthetic flooring like laminate flooring or vinyl plank flooring.

How Much Extra Flooring to Order?

Luxury Vinyl Plank and Laminate Flooring

Buy between 5-percent and 10-percent of extra plank or tile format vinyl or laminate flooring. Defective goods are rarely an issue with synthetic flooring, so the extra flooring accounts for the cut edges.

Ceramic Tile

Buy between 5-percent and 15-percent of extra ceramic tile. Tile size will have a bearing on wastage. Mosaic tile backing is easy to cut, allowing them to be reused elsewhere. In some cases, the mosaic sheets may even fit the space. Large-format tiles nearly always must be cut. Tile breakage is common during transit.

Wall-to-Wall Carpeting

Carpeting comes in long rolls that are either 12- or 15-feet wide. Carpet manufacturers recommend that you buy 10-percent more carpeting than you estimate for your floor's square footage.

Solid Hardwood Flooring

Natural flooring products should always be purchased in greater extra quantities than with synthetic flooring. Buy the amount of flooring needed, plus another 20-percent.

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.

Consider a 15-by-30-foot room with a total area of 450 square feet:

Engineered Wood Flooring

With engineered wood flooring, the defects are mostly engineered out. Buy 15-percent extra flooring to account for normal wastage.

Other Factors Determining Extra Floor Quantities

• If you are hiring flooring installers, err toward the higher excess amount. You never want flooring installers to stop work early due to a 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 often return the materials for a refund. Since some retailers may not do this (or may charge a restocking fee), confirm in advance.
• Conversely, if you bought the flooring online, returning the materials entails extra shipping costs that you will have to cover. So, keep the excess figures to a minimum.

Expected Flooring Installation Wastage

While wastage never sounds like a good thing, it's normal and even expected with flooring installation.

Wastage refers to the cut or otherwise discarded sections of flooring that do not belong in the floored space, some of which cannot be reused. Flooring manufacturers typically set broad wastage figures at 5- to 20-percent.

Nearly all flooring installation requires cutting. The most common reason to cut flooring is that 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 often can be used in subsequent rows. Plank remainders that are too short or otherwise unsuitable for installation become true wastage—debris for the dumpster.

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 are 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, results in even more waste materials.

Defective Flooring Materials

For solid hardwood flooring, expect that as much as 5-percent of the materials may be defective. Some of these defective materials may be repurposed in small areas or in closets.

Hardwood flooring may be missing tongues or grooves; it might be water-stained; it might be cracked or split; flooring exposed to the sun will be discolored.

Most hardwood flooring installers are experts at working with imperfect material. 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. Discolored or water-stained flooring can be used in less noticeable areas.

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.