From Beneath

• 1). Crawl under the floor and lie still. Have someone walk around on top of the floor to find the squeak. Listen for the noise to locate it. Go to the general area and have the person continue to walk or move on the squeak until you can determine the exact boards that are an issue.
  
  
• 2). Tap wood shims between the flooring and the floor joist where the squeak is. Use a hammer and tap carefully. You don't want to force the shims in further than you need them because you can raise the flooring to much. Tap one in slightly and have the person walk some more. Continue tapping it in until you reach the point where you no longer hear the squeak.
  
  
• 3). Nail through the side of the joist and up into the shim to hold it in place and keep it from working loose. Use a small nail to keep from splitting the shim.
  
  

From Above

• 1). Walk around on the floor to locate where the squeak is.
  
  
• 2). Pull up loose nails with the claw end of a hammer if you are working with hardwoods, or pinpoint the exact location of the creak. Drill in a snap head screw through the wood to connect the floor board back to the subfloor beneath. If you are drilling into a former nail hole, use a screw that is wider in diameter than the nail. The snap head is designed to snap off leaving the screw in place without the head.
  
  This process can also be done with carpeted flooring as well to remove a squeak in the subfloor by attaching it to a joist. However you will need to pull up the carpet, which is best done by a professional.
  
  
• 3). Dab on a small amount of putty over the hole. Wait for the putty to dry and then sand the surface of the putty so that it is smooth and even with the flooring.