Creaking and popping noises in a floor are caused by floorboards, fasteners, subfloor, joists and beams rubbing together. As you walk across the floor, the elements flex, changing shape and orientation in relation to the other elements. The creaking and popping noises can be stopped by isolating and securing the problem areas.
Mechanical Fasteners for Creaking Floor and Subfloor Surfaces
Use mechanical fasteners, such as screws and nails, to silence a floor that rubs on the subfloor or joists. Countersunk wood screws are better for securing a floor, because the teeth of the screw will not allow the floor or joist to work loose. However, 8 penny and flooring nails have a less conspicuous profile, and they will visually diminish in the floor surface. In either case, fasten the flooring to the joist and subfloor wherever there is a creaky area. If this type of repair is noticeable, fill the nail or screw hole with wood putty and let it dry. Smooth the putty lightly using an oscillating sanding tool or by hand with ultra-fine sandpaper and brush a small amount of the appropriate floor finish on top.
Joist Shims and Cleats
Wedge plastic or wood shims into gaps between the joists and the floor. The shims will stop the movement of the floor and the creaking or popping. For large areas of a floor that are noisy, screw 1x4 cleats into the joist at the bottom surface of the floor or subfloor. The cleat should push up on the underside of the floor, like the wedge, and run the full length of the joist where there is noise.
Old or weak floor structures may have joist flexing and shifting. To increase the structural integrity of the floor and stop the creaking and popping, brace the joists with 2x10 braces or steel bridging underneath the floor. The bracing will dramatically change the movement of the floor and the inherent noise.
Anchor Stair and Trim
Elements that come into contact with the surface of the floor, such as stair risers and trim, should be fastened to the floor surface with finish or flooring nails. The movement of the floor in relation to neighboring elements that are out of plane with the floor can cause creaking and popping.