How To Install Hardwood Floors

Proper preparation is essential for successful hardwood floor installation

Illustration of hardwood plans being installed on the floor

Wood flooring is one of the easiest types of floors to install. While other floors require mortar, stretching tools or floor-size patterns, you can install hardwood flooring with tools you are familiar with: drills, saws and hammers. Learn how to install hardwood floors on your own to cut costs and renting the tools you’ll need to get the job done.

Before you begin hardwood floor installation:

• Install on or above grade, not below grade.
• Leave wood to acclimate in the room you’re installing it in for five days prior to installation, at temperatures of 65°F to 75°F.
• Stack flooring log-cabin style or just spread it around the room, but not directly on concrete.
• If you will be installing the floor yourself, use a set of nail guns to speed up the process. If you don’t already have a flooring nailer, you can usually rent one at your local Home Depot store.
• Make sure you have an acceptable subfloor: ¾-inch CDX plywood is preferred and ¾-inch OSB is acceptable. Minimum 5/8-inch CDX existing wood floor or tongue-and-groove solid wood subfloor is also acceptable.


• Use caution when handling floor nail guns.
• Use knee pads to make installation more comfortable.

Tip: Estimate your hardwood flooring cost with this Home Depot Cost Guide.

What You Need

lay out the first row
Illustration of someone measuring the floor near a wall

Mark the walls to show the location of the floor joists. Cover the floor with 15-pound felt paper. For strength, run the strip flooring perpendicular to the joists. Start your layout at the longest uninterrupted wall that is perpendicular to the joists. At each end of the wall, measure out the width of a floorboard, plus 3/4 inches, and make a mark. Drive nails into the marks and stretch mason's line between them to lay out the first row.

Pre-drill holes for nails
Illustration of someone drilling holes into floorboards

The first and last rows of flooring have to be nailed through the face of the boards. All the other boards are nailed through the tongue only. To prevent splitting face-nailed boards, drill 1/16-inch-diameter holes for the nails, 1 inch from the grooved edge. Space the holes so the nails hit a joist or as directed by the manufacturer.

Fasten the first board
Illustration of someone hammering a nail into a board along a drawn line

Align the first board with the layout line, with the tongue facing into the room. Put a 3/4-inch spacer against the adjoining wall, and slide the end of the board against it. Drive 6d or 8d flooring nails through the pilot holes and then drill additional pilot holes through the tongue. Countersink all the nails.

Continue the first row
Illustration of someone laying hardwood boards

Put the next board in place along the layout line. Seat the end tongue and groove into each other and push the two boards together for a tight seam. Nail down the board, moving down the row until you reach the side wall. Cut the last length to fit, leaving a 3/4-inch expansion gap and nail it in place.

Rack the flooring
Illustration of someone installing hardboard boards against each other

Spread the boards from several bundles across the room. Mix bundles and mix shades, colors and lengths, using the natural variety in the wood to create a random pattern. Lay out the boards in the order you will install them. Pros call this "racking the boards." Flooring bundles tend to be uniform in color and if you don’t rack them, you will create noticeable light and dark areas in the floor. Make sure you finish the process by arranging the joints so they are sufficiently offset across the floor.

Install the next rows
Illustration of someone hammering multiple boards together

Put the first board of the new row in place. Cut it, if necessary, so the end is offset from the end of the board in the previous row by a minimum of 6 inches. Put the end against a 1/2-inch spacer and seat the edge snugly against its neighbor. Drill pilot holes in the tongues and then nail and countersink them through the tongues (but not the faces) to hold the boards in place. Work your way down the rows, one row at a time.

Continue With flooring nailer
Illustration of someone using a flooring nailer on boards

Switch to a flooring nailer as soon as you can. After installing the second or third row, you will have enough room to get a flooring nailer between the wall and the board you are placing. Position the nailer so it will drive a nail through the tongue of the board, then hit it with a mallet to shoot the nail through the tongue. Adjust the air pressure as needed so the nail countersinks into the tongue.

Install the remaining rows
Illustration of someone using a flooring nailer to install hardwood boards

Work your way across the room, row by row, power-nailing the boards through the tongue. Leave a 3/4-inch expansion gap between the end board and the wall. Stagger the ends of the boards in adjoining rows by 6 inches and rack additional bundles as you go.

Straighten any bowed boards
Illustration of  someone tapping hardwood boards into place

Even the best flooring comes with pieces that are not perfectly straight. Set these aside initially; if these end up as extras, you won't have to use them. If you must use a slightly bowed piece, drive a chisel into the subfloor and pry against the edge of the bowed strip to straighten it. If the piece is badly bowed, screw a piece of scrap to the floor about 1 inch from the strip. Tap a wood wedge into the gap, as shown, to straighten out the board.

Framing around obstructions
Illustration of someone nailing hardwood boards into place around a corner

Often a floor will meet an obstruction such as a fireplace or counter. If so, miter boards to create a border that frames the obstruction. Position the boards so the tongue or groove mates with the rest of the floorboards. Cut off the tongue if it is on the edge that meets the obstruction. Apply the rest of the floor as you normally would, fitting the pieces into the frame as you go.

Cutting corners to fit
Illustration of someone marking an indentation on a hardwood board

Where the flooring meets a jog in the wall or a similar obstacle, cut corners to fit. Snug the piece of flooring against the obstacle and lay out the cut by marking where the edge of the obstacle meets the board. Allow for a 1/2-inch expansion gap at the end of the board and a 3/4-inch gap along the edges; make the cut with a jigsaw.

Face-nail the last rows
Illustration of someone nailing in a final row of hardwood flooring

As you approach the wall on the far side of the room, it becomes difficult to use the flooring nailer. Once you don’t have enough room to swing the mallet, begin drilling pilot holes for face-nailing, but nail only when you have laid down all the boards.

Cut the last row to fit
Illustration of someone using a crowbar to squeeze in a final row

You will probably have to cut the width of the boards in the last row to fit. Measure the space and subtract 3/4 inch for the expansion gap. Cut the boards to width on a table saw. Put the boards in place. Pry against a piece of scrap on the wall to seat the boards and close any gaps between them. Face-nail to hold the boards in place.

Install the trim
Illustration of someone installing hardwood flooring trim

Install the baseboard and shoe moulding to cover the expansion gap. Keep the lower edge of the baseboard even with the top of the floor and nail the baseboard into the wall. Set the quarter-round shoe moulding on a piece of paper to keep it just a hair above the floor. Nail it to the baseboard, not to the floor or subfloor. Nail threshold or transition strips in place where the edge of the floor is exposed.

Illustration of two hardwood boards joined by a joist

Flooring in a hallway should run the length of the hall regardless of joist direction. If the flooring will meet wood flooring in other rooms, install the hallway flooring first, then work your way into the adjoining rooms. To make this work, sometimes you may need to join two boards groove edge to groove edge. If so, cut a strip of wood, called a spline, that is wide enough to fit into one of the grooves and about halfway into the neighboring groove. Glue it into one of the grooved boards and nail it to the floor. Slip the groove of the neighboring board over the new splined tongue.