Pilot Hole
Affiliate link — we may earn a commissionA pilot hole is a small-diameter hole drilled before driving a screw. The hole should match the screw's root diameter (the shaft minus the threads) so the threads bite into wood while the shaft slides through without splitting the grain. In hardwood, the pilot hole is mandatory. In softwood, it depends on how close you are to the edge. Within 2 inches of an edge or end, drill one. The middle of a wide board is forgiving enough to skip it with construction screws. Standard pilot hole sizes: #6 screw gets a 3/32" hole, #8 gets a 7/64", #10 gets a 1/8".
Why It Matters
Driving a screw without a pilot hole into hardwood or near the edge of softwood splits the board. The screw acts as a wedge, pushing wood fibers apart until the grain separates. Ten seconds of drilling prevents a cracked board and a wasted cut. Especially on trim and finish work, always pilot.