Install hardwood flooring

1.1  Hardwood flooring can be installed over a traditional joist-and-beam framework or on top of a concrete slab.
Hardwood flooring is not recommended for the basement, where humidity levels are generally too high.

1.2  If installing over a wood framework, screw sheets of ¾" plywood to the floor joists with flooring screws.
Firmly securing the plywood in this way prevents it from moving, which can cause the floor to creak. Clean the subfloor surface and make sure it is smooth before laying the non-tarred felt paper.

1.3  If installing over a concrete slab, the substrate must be smooth and flat.
Level the surface if necessary. The subfloor is made up of two layers of plywood of at least ½" thick, the first layer of which is positioned so that the long side of the sheet runs parallel to the longest wall. Leave an expansion gap of ¾" along the walls and 1/8" between each sheet of plywood. The second layer of plywood must be laid over the first at right-angles. Screw the two sheets of plywood together but do not screw into the concrete. Clean the surface of the subfloor and make sure that it is smooth before laying the felt paper.

1.4  Cut the base of the door frames to be able to insert the planks and remove all edgings, baseboards and quarter-rounds, as well as door thresholds.

2.1  Lay a plank (finish side down) next to the door casing and mark the casing with a pencil line at the height it needs to be cut to allow the flooring to fit underneath.

2.2  Cut the casing with a backsaw.

2.3  Slide the floor plank (finish side up) under the casing to check the height.

2.4  Repeat for all door casings and closet door frames.

3.1  Staple the non-tarred felt paper to the subfloor.
This underlayment forms a moisture barrier and helps reduce footfall noise.

3.2  Decide the layout direction for the planks.
Unless the subfloor has been reinforced as described in the previous step, the planks should be laid either at right angles or at 45° to the floor joists.

4.1  The planks must follow the line of the wall.
While planks can be cut lengthwise, they must always be a certain minimum width if they are to stay firmly in place.

4.2  Calculate how wide your last row will be.
Check the manufacturer's recommendations regarding the minimum width of planks. If the width of your last row is going to be less than the minimum required by the manufacturer, adjust your measurements so as to reduce the width of the last row.

4.3  Check that the wall is straight and square.
If it is not, you will need to cut the planks in the first row lengthwise to follow the wall line so that all the following rows of planks are perfectly square.

4.4  Measure the width of one plank and add 3/4" for expansion.

4.5  Taking the previous measurement, snap a chalk line the same distance from the starting wall and parallel to it.
Double-check that this guide line is perfectly straight and square.

4.6  Decide which planks to use and in which arrangement for the first four or five rows.
Choose the straightest full planks for the first row.

5.1  Lay the first plank along the guide line, grooves facing the wall.

5.2  If the plank needs to be cut lengthwise, scribe the wall line onto it by sliding a small block along the wall and, with a pencil, tracing the corresponding profile onto the plank.

5.3  Saw the plank lengthwise along this cutting line.

5.4  Measure the length needed for the second plank and cut if necessary.

5.5  Use spacer blocks or shims to keep a ¾" expansion gap all along the wall.

5.6  Leave an expansion gap of 1/4" at each end of the row.

5.7  Start laying the second row with a length of plank left over from the first row.

6.1  The first row must be nailed by hand, groove facing the wall.

6.2  To do this, bore 1/16" pilot holes in the planks at a 45o angle, ½" from the grooved edge.

6.3  Start about 2" from the end of the planks and space the holes every 6".

6.4  Align the first plank with the guide line and drive nails through the pilot holes.

6.5  Sink the nail heads with a nail set.

7.1  For the following rows, use a pneumatic or manual nailer.

7.2  Continue spacing the nails every 6".

7.3  Never nail less than 2" from the ends of the planks, otherwise the wood may split.

7.4  Stagger the joints by 6" to 8" with those of the previous row and alternate the length of the planks.

7.5 For the last row, you may need to cut the planks lengthwise. Remember to keep an expansion joint of ¾" along the wall.

7.6 Manually nail the last row the same way as you did the first.