Hardwood floor squeaks multiplying - fixable?

[zaius]

Some background: Three story townhouse, almost five years old now. Second floor has brazilian cherry site-finished hardwood over plywood subfloor. The ceiling below (bedroom and garage) is finished, so no access to the joists.

With squeaks under hardwood am I just doomed to have them multiply and ruin my resale in a few years? The neighbors report that they have no squeaks at all in their wood floors. Oddly, the loudest four squeaks are all roughly in a straight line across the second floor of the house, but this could just be coincidence since it's high traffic areas. I hope it's not a house settling issue.

So my questions to you all are:

1) Why would several areas start to creak in such a short amount of time? Does that imply a structural issue?

2) Is this common in such a new building?

3) Will a contractor realistically be able to fix most pops/creaks when the time comes to sell the place (without having to remove the hardwood planks)? I would likely bring in a contractor to do it, since "squeak no more" kits require guesswork drilling through the hardwood.

It could just be normal wear and tear, but we don't do anything the neighbors don't, so why they don't have squeaks is a mystery.

[HayZee518]

before you even consider a contractor, get some unscented talcum powder in a poofer bottle and poof it along the cracks in the hardwood. brush off or vaccum the excess. the talcum lubricates whatever the boards are rubbing against.

[zaius]

I would consider that, except it sounds like it really must be either a gap under the hardwood, or more likely stepping on the spots pushes a nail down (because you can hear it crack and pop it's way back out, like the carpeted areas upstairs).

Also, would powder penetrate tongue and groove hardwood?

[HayZee518]

the powder is microscopic so it should work its way into the groove. you said something about a carpeted area. I saw something on the discovery channel about a snap off screw head used to fasten boards on a squeaky floor. it's a two headed screw that's applied with a special driver. after the screw is applied, a groove fits the screw head and it's snapped off hiding the actual fastening part within the carpet's nap.