What causes squeaks in hardwood floors?

Most commonly, squeaky hardwood floors are caused by parts of the floor or subfloor rubbing against each other or the nail that is holding them together. Many older houses were built without adhering the subfloor to the joists with subfloor adhesive. As a result, the wood joists and subfloor settle and dry out over time, causing them to pull apart from each other. Yet, the nail holding them together remains firmly in place. Thus, when the subfloor moves up and down (i.e. walking on it), it rubs against the nail, making an annoying squeaking noise.

Whether your hardwood floors were installed years ago or are brand new – you can get hardwood floor squeaks. These are not the fault of, or caused by, your hardwood flooring professional.

How to Repair Squeaky Hardwood Floors

If you have an unfinished ceiling below the floor, have someone walk across or rock the area of the floor making the squeak while you are below to determine its location. Once the squeak is located, use a hammer to place wood shims in the gap between the joists and the subfloor.

If you have a finished ceiling, locate the squeak by stepping on that area of the floor. Then you must become a detective and locate the joist that the squeak is coming from. This can be accomplished by locating top nails, generally concealed with putty to match the wood color, in rows along a parallel wall, but still visible if you’re really looking for them.

Squeaky floor example

Above is a rough (okay … very rough) illustration of your rows of flooring, with the dots representing top nails 16 inches apart, vertical lines representing walls, and spaces between horizontal lines representing floor boards.

Measure from Wall B to the squeak. Now measure that same distance from wall B to the top nails * in the joist that line up best with the squeak.

The idea is to find the joist nearest the squeaky area to nail into. Using a ten penny finish nail and a drill with a bit slightly smaller than the nail, drill one hole through the center of the flooring board. By drilling a smaller hole first, you avoid splitting the wood.

Next, hammer a ten penny nail into that hole. You will know if you hit or missed your joist by the resistance when hammering. It’s hard work nailing into the joist.

Set the nail below the surface of the floor and use wood colored filler (putty) to conceal it. Test the area (walk on it) to ensure the squeak is gone. If it’s not gone, follow these instructions by placing another nail two to three rows away from the first nail you placed. You don’t want to put too many nails in one area.