I'll start by explaining how squeaking floorboards starts.

Quite often, over a period of time, the flexing of the floor or
expansion and contraction of the timber may loosen floorboard nails.

It is the resulting movement of the wood against the nails or against
the neighbouring boards that produces the typical irritating squeak.

The simplest cure is to drive the floorboard nails in deeper with a
nail punch, which allows the tapered edges of the nails to grip the
wood more securely.

We have found that sometimes, however, this may not be a lasting
solution.

If the problem persists, use either a larger or ring-shank nails. You
can buy all of the items I talk about from general DIY stores - I'm
sure that you will have a local store to you. Alternatively companies
like Screw Fix or B&Q or other DIY stores should be able to help.

Using larger nails or ring shank nails will give a better grip as they
are designed for situations like creaking floor boards; however they
need to have clearance holes drilled through the boards. I would
recommend you use a normal electric or hand-drill to do this.

The clearance holes must be slightly larger than the diameter of the
nail to ensure that they grip the bottom of the board securely.

After you have put the nails in make sure that you fill any redundant
holes with matching wood filler - the closer the colour match the
better. You can almost completely disguise the nail heads this way.

If the boards can't be re-nailed satisfactorily (for example, because
of twisting or bowing), use countersunk stainless-steel woodscrews.

Remember that you need to bury the heads of the screws deep enough to
cover them with filler or with matching wooden plugs. I also recommend
that you dampen the wood thoroughly before fixing - this makes the
wood 'give' and allows the screw heads to essentially be countersunk
as the boards are screwed down.

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