Rat? Squirrels? Other rodent I would imagine. Good luck!

Is it just one bang? Or several bangs that are spread out in time?

several bangs spread out in time randomly.

Nail pop

Your new house is made of a million new connection points and as wood expands and contracts it is going to squeak and pop. Even wood that is kiln dried adjusts to relevant humidity so i would not worry about it.

Over time it will settle out. If you said an older home i might be worried…

It’s the wood. My house does that too. The attic usually has bigger temperature and moisture changes than the rest of the house.

Thanks everyone...How loud these noises can be...The ones I hear are very loud and wakes me up in the middle of night. I am wondering if there is someone who can go in the attic and inspect and confirm there is nothing structurally wrong and its just usual settling noises.

Shortly after delivering a home, the buyers were convinced it was about to collapse. We peeled back a piece of upstairs hall carpeting, cut out a section of sheathing exposing an air return and substituted a metal endpiece with wood. Problem solved. (Probably not to Code today.) IOW, it could be ductwork contracting and expanding against fasteners.

As a child, I remember all our tract build wood-frame, shingled homes creaking and groaning, especially in the winter.

I would go up into the attic and just sit there for a bit at the time you have heard the most noises. Look to see if you see daylight anywhere coming into the attic. Yes, it's probably some settling making noises. But, my bet is on squirrels. They sound like a whole jungle gym of toddlers when they are in your attic.

Hi,It may be a damper, they a found-on bathroom and.kitchen vents, They are flappers inside the vent pipe used to prevent are from coming in but some time the wind outside will cause a vacuum and cause the flapper to open and close.

Good Luck Woodbutcher

My bathroom vents dampers are plastic and would never make a loud bang. My kitchen vent is still more like a tingle and not a loud bang.

Is there wind? OP didn't mention it but possible.

Do you live in the desert or somewhere it gets very cold at night. This would accentuate the expansion and contraction.

I have never been woken by loud noises from the attic despite living in multiple new homes. I have had trusses on one of them and I didn't have that.

Was the house built quickly? Because generally, nowadays, things are so slow that I would expect the wood to be well dried out by the time you more in.

Are you hearing any moaning or sounds of pain from the attic at night? Sounds of a rocket motor coming in for a landing or leaving?

Asking for a friend...!

@David Cary : Here is info you asked :

We are located in San Jose, the variation of temperature is +20 degrees between day and night.

There was no wind when I hear these noises.

The house took 10-12 months to build. When the framing was done along with truss installation, out work halted fo 2.5 months due to some missing paperwork and it was during summer last year so all the framing and trusses were exposed to heat for almost 2.5 months...By the time rain started in december the house was already water proof.

I am trying to reach out to the contractor so that he can come and check in attic whats happening but he is not responding so trying to see if I can find someone to inspect attic.

Could be a fault line moving underground. The Calaveras Fault runs along the east side of the San Jose metro region. It is a zone of active, right-lateral, strike-slip faults, which compose a major branch of the San Andreas fault system.

Surprised San Jose is only 20 degree differential this time of year. It does sound (your description) like expansion and contraction. Presumably this only happens at night which further plays into contraction noises. I don't think rodents/animals would sound like what you describe and I would be pretty surprised if they got into a new house so easily.

Now the fault thing I have no idea on but not sure why that would be attic noise.