I moved into my new house last August, so a little over a year ago. I noticed that the hardwood flooring would always crack and pop as I walk through the house. There are a few spots that I can stand on and make them squeak but all of the others ones I cant make them pop or crack after I walk over them, it seems to travel. When the builder was building the house over the spring and summer, I saw the hardwood accumulating in the house for about a month before it was installed. After complaining for 8 months, they finally sent someone out there and he told me it was the second worst house he saw that was like this. The first one was because they didnt heat or cool the house at all. Ever since I moved in the house has maintained 70. The floor inspector claimed that the sub floor had to be uneven, which I dont think is true. The builder then told me it was because I didnt have a whole house humidifier. I'm a rehabber but dont specialize in hardwood flooring. I own about 10 houses with hardwood that is at least 50 years old. If it squeaks I know I can fix it but not of rentals do this cracking or popping and these houses have been beaten over the years. I dont know what to do other than reach out to the manufacture. I attached a link to my google photos, I dont know if it will show it or not. Any help is appreciated!

https://drive.google.com/open?id=12iXOL ... EV-ziq0NRQ

The noise is caused by movement. What was used to fasten the floor? Was the manufacturers nailing schedule followed? This looks like an engineered floor.
Engineered flooring is very stable.

Its real hardwood. I'm going to be finding out the make and everything in the next couple of days. The floor inspector claims they used plenty of nail in securing the wood. I know this doesn't really answer your question. Sorry.

I think its from movement also. From seeing this you would think it has to do with the nails verses the sub floor? How many nails do you recommend per plank?

If the flooring is fastened within 2 inches from each end, which means each board has at least 2 fasteners, and every 6 inches you have a well fastened floor. The sub-floor has a different nailing schedule.
The milling could be sloppy, so the tongue doesn't fill the groove. T&G flooring is only fastened on one side of the board so the T&G where the boards meet needs to be accurately milled to prevent movement.

Sub floor could have dried out as well creating shrinkage. Nails loosen their previous firm grip. Squeaks occur.

Dry out periods are necessary. Did anyone pay attention to this?

All I know is that the flooring was inside my house for about a month before it was installed. Is that what you are asking about?

Did anyone document the subfloor's moisture content prior to installation?
Did it rain on the subfloor during construction?
Is the subfloor OSB or plywood?
Was the HVAC on during the acclimation period?

I dont think that floor's mositure was documented. Is that standard practice?

I dont know if it rained or not.

Subfloor is OSB.

I would think the HVAC was on because it was hot outside when they were installing it.

Also, I dont know if the builders did this to my house but I think what they do is have a big torch in the house hooked up to a huge propane tank and seal up the house to draw out all of the moister. I'm not sure what they use that for. Maybe they could have been a problem.

Absolutely! It is one of the first thing that is required. OSB has a tendency to swell a lot when it gets wet then it does not shrink back to original dimensions causing it to be less dense than when it's new. That causes fasteners to loosen easily. Or what Ken said.

The use of propane is bad, the burning of propane produces water vapor. Then depending on the ambient conditions it can condense on surfaces like your subfloor making it even wetter.