We would so appreciate any advice here. My husband and I installed a hickory 5 inch plank floor to our kitchen, foyer and upstairs hallway. We took the advice of the flooring person at Lowe's and used a felt under padding. Due to gapping between the planks I had a flooring contractor come in and assess the floor. According to him the padding should never have been used. I approached Lowe's and they contacted Mohawk and received confirmation that what they recommended was appropriate. So what now?? We are left with gaps any where from 2 to 7 mm in width. Is this type of gapping normal. We did follow the recommended installation steps to the letter. Pneumatic nailer, wood glue between the seams. Any advice would be greatly appreciated.
Thanks,
Kristen from Minnesota

Lots of missing information there. Type of install, glue, float, nail? Type of underlayment? Any moisture testing done?

We used Elmer's wood glue on tongue and grove. It is not a floating floor, it is nailed using 2 " nails to a new plywood sub floor. The under padding is called Insulayment, a special order from Lowe's. There is no detected moisture problems.

Any moisture testing done prior to installation??

How long did you let the material acclimate? When was the floor installed?

Sounds pretty normal to me. What the great people at the big box dont know is how bad 5" hickory moves while in service. Check the r/h in the house (my guess is its in the teens or lower) if so buy a humidifier and get it up to a more comfortable level, ideally 45%. Wood shrinks as it dries out, wide planks and certain species like hickory will move even more when exposed to environmental conditions that are extreme one way or the other. Stabilize the r/h and the floor will behave like it should.

Hickory is like a little rascal, give it an inch and it will take a mile

Ive had more movement problems with hickory than any other domestic specie out there, It's popular in this area due to the fact we have a ton of rustic mountain cabins and lake homes, so I would say watch out for that stuff.

Many thanks to all. Entirely new 3/4 plywood subfloor glued and screwed to 16" on center joists. Will check r/h. It was acclimated in the house last Feb for two weeks prior to a winter install. Had some concern about over swelling during humid summers which did not occur. But this winter the gaps really appeared.