How to Install Hardwood Floor in Adjoining Rooms

Unroll underlayment on the floor of the hallway. Use as many underlayment rolls as you need to cover the length of the floor, overlapping the edges of adjacent floors by several inches. Staple the overlapping edges to each other and the floor with staples every 6 to 8 inches.

Snap a chalk line along the edges of the largest room, preferably the hallway, 1/2 inch from each wall. The 1/2-inch difference is the expansion gap that you will later cover with trim.

Lay the first course of hardwood planks along the chalk line, with the grooved edge facing the wall. Slide the tongue edge of each plank in this course into the grooved edge of another to join them, forming tight seams.

Shoot flooring nails every 10 to 12 inches along the edges of the hardwood planks in this course. Rip the last plank in this row using a miter saw so it fits the gap between the edge of the previous plank and the wall.

Lay the second course of planks next to the previous course but stagger their joints by several inches. Slide the grooved edges of these boards into the tongue edges of the previous course to lock them together. Nail the boards to the subfloor and continue the process of installing the planks on the floor until you lay the second to last course.

Measure the exposed gap on the floor onto which you will lay the last course. Rip the planks to the required width, minus the expansion gap, and repeat the process to lay them on the floor.

Remove the door’s hinge screws to loosen the door and set it aside. Place a hardwood plank on a piece of underlayment and measure the thickness. Transfer this measurement to each doorjamb along the doorway.

Cut along the marked lines with a handsaw. Loosen and remove the wood along the lower end of the doorjambs.

Measure the gap between the doorjambs and cut planks 1/2 inch smaller, to allow for expansion. Roll underlayment between the doorjambs, extending it into the adjoining room. Slide as many planks as you need under the jambs to cover the doorway. Shoot nails through the edges to secure the planks to the subfloor.

Snap a chalk line 1/2 inch along the edges of the wall in the adjoining room. Repeat the process of laying underlayment on the floor and courses of planks until it is covered.

Lay lengths of trim or baseboard above the floor planks along each wall to cover the expansion gap. Nail the trim to the wall.