Creaking floorboards are very common for us to find when conducting a snagging survey in new build houses. The location of where it occurs can often move through the settlement process or disappear altogether after a short time. Having said this, a large amount of the houses we inspect months or years after completion still have squeaking and creaking floors.
The most common reason for floors creaking are:
It is important that joists are fixed solidly at either end of the room and spaced at the correct centres (usually 400mm) and cannot move in their wall sockets or joist hangers. The tail of the hanger should be firmly built into the wall and the joist firmly fixed into the hanger. Only an intrusive investigation would identify if this is the cause of the noises experienced. A joint acoustic study at the University of Salford with the NHBC identified the loudest noise came from these sides of the wall: either due to the junction between the joist and block work party wall / external walls or where it meets the plasterboard wall/ceiling lining.
In an attempt to prevent vibration from the boards travelling through the room below, builders have resorted to resilient bars which essentially create a floating ceiling separating it from the plasterboard underneath where the noise is bridged. To achieve this,
insulation is installed between the timber joists with an acoustic mineral wool, then the resilient bars are affixed to the timber joists. Then several layers of acoustic grade plasterboard are packed in with a layer of acoustic membrane.
Whilst a slight creak can be easily solved by accessing the fixings under the carpet, often customers encounter a cracking noise which indicates an issue with the strength of the joist rather than movement in the floor board.
Cracking noises (like a pencil snapping rather than a creak) often requires more intrusive structural remedy such as installing noggings, which provide more rigidity to the joists.
A Snaggers Blog
HomeSnag inspectors are experts at inspecting new-build houses. This blog shares real examples to demonstrate the importance of getting your new build house or apartment snagged professionally
"I always insist that there is specific provision for snagging," says Thomas Moran, partner at law firm Speechly Bircham. "Reputable developers do this anyway, but there are all sorts in the market, some big, some small, so you need a contractual promise than within, say, a year they will come back to remedy any minor defects in the finishing."
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