Plywood Trailer Floors
Measure and sketch out the trailer floor with dimensions on paper. Measure and mark the locations of any fasteners that pass through the metal frame, with dimensions. Measure the individual panels of the floor and mark those dimensions on the drawing as well.
Remove screws from the decking with a cordless drill or release carriage bolts in the corners of the panels by loosening the nuts from below the trailer with an impact gun. Replacing fasteners is the best way to ensure a long lasting replacement floor. Save one screw or bolt as an example.
Cut plywood pieces the same sizes as the original. This will allow the frame pieces to fall in the same place so that fasteners can be reinstalled. Drill bolt holes in the locations you indicated on your drawing with a bit the same diameter as your bolts. Drill 1/8 inch pilot holes through the plywood in each screw location.
Purchase enough bolts or screws of the same type and size as the originals to replace the original fasteners and a few extra in case of loss or damage. Position the plywood pieces into the trailer frame in the same pattern as the originals. Drive screws through every screw pilot hole or insert a carriage bolt, with a firm tap from a hammer to set the head, into every bolt hole. Thread a washer and nut to the bottom end of each bolt and tighten with the impact gun.
Purchase enough lumber in the same thickness and width as the original pieces to cover the trailer floor. Measure and sketch out the floor including each plank. Mark dimensions on the drawing. Mark the location of each bolt as well.
Unbolt and remove the planks from the trailer's frame using the impact gun from underneath the trailer deck. Buy enough new bolts in the same type and size to replace the originals.
Cut the new flooring pieces to length, using the original boards as a pattern. Mark each plank to indicate the order and placement for installation. Drill holes, the same diameter as the bolts in each location you marked on the drawing.
Position each plank according to the predetermined order in the trailer frame. Push a carriage bolt through each pilot hole and give it a firm tap with a hammer to set the head. Thread a washer and nut onto each bolt from underneath and tighten with the impact gun.