The main purpose of face nailing is to minimize a cupping appearance with wide plank floors.
Face nailing needed for 12 inch wide plank floor.
Regardless of how many nails you choose to use per row you are replicating the method of using hand forged nails hundreds of years ago.
On 8 wide boards you may choose either 2 or 3 nails per row.
A 4 wide plank is still begging to be face pegged as i mentioned also in the article.
Entails using adhesive in addition to nails even if you re installing a solid wide plank floor.
It just depends on how narrow you indoor humidly range is.
In renovation work most product is staple nail down over wood subfloors.
This is done by introducing glue to the nailing process.
When stapling nailing down you only have the fastener holding the edge of the board down.
Which works very well with plank flooring to.
On 10 and 12 wide planks use 3 nails per row.
As this prevents the hardwood floor from expanding.
Regardless if installing a 3 wide engineered hardwood or a 5 wide engineered hardwood plank you are not using any more fasteners despite the increased width.
Installation of wide plank flooring nail down installation of wide plank solid and wide plank engineered flooring requires additional bonding to the subfloor to prevent movement and squeaks.
Extremely wide boards 8 to 12 inches wide require three nails instead and boards under 4 inches use one nail.