Flooring clamp

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A flooring clamp is a tool used to hold tongue-and-groove floor boards in place while they’re nailed down. It can clamp about 8–10 boards at once. Usually you need at least two clamps, but more are common. Place clamps roughly every 4th or 5th joist. Set the clamp over a joist (35–65 mm thick), then tighten the ratchet to press horizontally on a sacrificial bearing board (about 100×50 mm) to keep the boards straight for fastening.