I had carpet installed just under year ago but have started to notice it's squeaking in certain places and was wondering what could be the cause.
The original floor is tiled rather than wooden planks and the carpet was installed with underlay.
I've started noticing it in more and more places and it's getting to a point I need to consider taking it up with the installer if this is something caused my a bad installation.
What may be happening is the padding under the carpet is not attached to the floor. Since the installer could not hammer staple the padding to the tile (ceramic?) floor it should have been glued with an adhesive made specifically for carpet padding. Glue is applied to the floor so that a continuous bead of glue will contact the edging of the pad. Also, a less likely cause maybe the carpet itself is loose. To check, at the center of the room that is producing the noise, pinch the carpet nap and pull upwards. The amount of carpet that is pulled away from the floor should be minute. If not it will need to be re-stretched and the tackles checked.
I know this question was asked ages back so I thought I'd update and put the mystery to rest.
The installers came around and lifted the carpet. For some reason the underlay was making the squeaking noise. They cut a small section away, around 1 inch squared and the noise went away! They're not 100% sure why it was making the noise, possibly a manufacturing fault.
Thankfully the problem was not particularly serious