The 'Squeak No More Kit' is designed to be used from above, through carpeting, which means you aren't required to have access to the under-floor area. Unlike other floor creak kits, the Squeak No More uses screws, which screw down into the floor, securing it firmly to the joist.
The 3/16" coarse thread of the special screws included in the kit are designed to go through the carpet, rather than grabbing the nap of the carpeting. Driving a screw through carpet can be a little worrying for some, but you can always test out the screws by trialling them on a piece of carpet which is normally not exposed. Move a piece of furniture and do a trial run if it helps put your mind at ease.
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What is a floor joist?
If you're new to the realm of floor repairs, floor joists are simply part of the supportive structure of a floor. A major cause of squeaking and creaking is the sub-floor not being properly secured to the joists. The sub-floor is the layer below the finished floor.
How do you know where the floor joists are located beneath your floor?
The kit includes special screws designed to be used to locate joists. (see instructions for use).