Hello folks,

I'm looking for a bit of a reality check here. My wife and I bought a new home (typical subdivision home) that we're excited to close on in just over a month.

We went to check on the place last week and peered through the window and saw that our flooring had been installed. I know the flooring had sat in the house for 1-2 weeks prior to install, but the house is currently only heated by electric heaters and i'm assuming must be VERY dry.

Anyhow, we went with a 5" engineered white oak flooring and I'm quite happy with how it looks, however there are some gaps that I noticed while peering through the front door that have me bothered. They can be seen in the photo below. The gaps are on the ends of the boards, not the edges. It's hard to tell from the photo since it was through the door, about 8-9 feet away. That said, it looks to me like the gaps might be approaching the thickness of a credit card.

Now, I'm a self proclaimed perfectionist -- to my detriment -- so I'm looking for some advice to know whether this is "acceptable", or something that should be pushed back on. Furthermore, so that I have some knowledge when speaking with the builder, I'm curious about possible "fixes". At this point, I'm unsure if the flooring is floating (I'd be VERY surprised if this was the case), if it was nailed, glued or nailed and glued.

I'm a hobby woodworker and understand wood movement somewhat, and also know that most "fillers" aren't ideal as they are prone to cracking and shrinking. That said, I have heard good things about Woodwise and I've personally used Timbermate products in the past and quite like them -- however I know idea about the suitability of such products on pre-finished floors.

Alright, enough rambling. Any advice would be terrific and greatly appreciated.

Photo here -- tried to use the img tag to embed the photo, but kept getting an error.

https://postimg.cc/Wdfd52gL

The end of the planks may be shrinking with the dry conditions in winter with the electric heat. The ends will shrink sooner than the middle of the boards. The important thing is to install midway between the humidity of your house between summer and winter. The installer sometimes purposely will leave small gaps in the winter that will most definitely close up during the summer.
It would be more of a problem to have the planks expand too much and have cupping in the summer. The electric heat may be drying sheet rock, paint or grout so it ought to be operating, with a thermostat.