Gapping is normal for this time of year.

Agreed. Wood shrinks this time of year.

Thank you all for your responses. is there a reason then that we don’t see any gapping in the ’older (4 year old) floors’ and have never seen them but they are there now in the newer section this first winter?

Pretty sure, your old flooring has gaps in it to. You are use to it, so, it is not as noticable. New flooring will have a higher MC value. Overtime it will be reduced. Also, your flooring was installed back in July or August, which has the highest humidity level of the year. So, your MC value is more on the higher side when the flooring was laid. Post images of the old floor.

If you bump up the humidity in your house they will close up. Normal winther behavior in heating climates. Your older floors may have been laid in a drier season and be slightly tighter. A 1 foot wide white oak board will swell and shrink by about 3/32" over the course of a year with typical northern humidity changes. You probably won't notice it with narrow boards, but with wider planks, or if your strips are stuck together with finish, the cracks will certainly show.

Hi G&S, floor was installed last March. photos were from Oct/Nov. Here’s a couple of the 4-5 year old floors.

Your timeline does not add up. You mentioned floors put in 7 months ago. Which would put us in July and August. But in your last post , you mentioned it was put in March. What happened between March and October?

G&S, my apologies for the confusion. I was calculating the 7 months from when we first started to see the separation. To clarify, the floors were installed in March. We started noticing the separation in Oct. From Oct to now, the gaps have become more prevalent (wider/longer). The photos below (both new floor with gaps and the photos you requested of the old floor) are current. Thank you for your response.

When was the floor sanded and finished?

Hi G&S, the floor was sanded and finished the first week in March.

Flooring was put in March and then sand and finished in March. You would need to find out if, the flooring was properly acclimated. Humidity and moisture content levels before, during and after installation, jobsite environment, etc.