Why do floorboards creak?
Creaking floorboards can give a house character and start rumours of ghosts and haunting. However, they can also severely annoy the neighbours, particularly if you live in a top floor apartment and walk around your house late at night. To avoid bad relations, it is best to identify the source of, and fix, the problem.
If boards have been lifted for central heating or electrical wire then they can develop a creak when they are replaced as they are slightly loose. Creaking can be accentuated if the floorboards are not tongue and grooved as this means that they will not slot into each other, causing the wood to rub together when people walk on the boards.
Lack of Joist Support
If the joints of the floorboards feel springy when you stand on them, then there is likely to be a problem of joist support. Here, due to a lack of support, the floorboards move up and down when people walk on them. This causes a creaking noise.
To save costs, developers often use chipboard flooring instead of genuine floorboards. Normally, the flooring is attached to the joists using 2-inch ribbed nails. However, the joists can settle in a matter of weeks, and the central heating pipes underneath the floorboards can cause the boards to warp out of shape. Consequently, they do not slot into place and slide up and down the ribbed nails, causing a creaking sound.
Fixing the Creak
Loose boards can be fixed by sprinkling talcum powder or chalk on the joints of the floor (although this is not a permanent solution.) Alternatively, you can replace the nails with screws, as these will stop any movement of the board. However, the nail and the screw must be the same size, or pipes or wiring could be damaged. The floorboard can be supported by lifting up the board and fixing a 25mm x 50mm batten on the joist's side using long screws.
Never put a nail or screw into a floorboard unless you know what is underneath. This could include wiring and water pipes that could break. You can lift the boards to find out or use a battery operated cable and pipe detector to find out. Make sure you mark the areas that you have checked. If you are putting screws into floorboards you must countersink the screw-heads or they could stick out, catching on feet or clothing.