Putting down a solid 3/4" x 3 1/4" White Oak floor on a plywood sub floor. The guy where I bought it said 1/4" gap between the wall and edge of floor was what you need. I've seen everything from 1/4" to 3/4" mentioned in the various articles and videos. The floor will be a total of 11' wide and then a hallway of 44" wide. Its in Redwood City, CA area (San Fran bay area) and temperature and humidity is pretty moderate year round. I would like to use 1/4" or I could go to 3/8" since plan is to have 1/2" thick baseboard over it. Looking for advice on this.

What do the manufacturer's installation instructions specify for expansion gaps? The usual expansion gap is 1/2" to 3/4" parallel to the boards. Expansion gaps at the ends of rows is neglible. I wanted a 3/4" gap and had a 1/2" baseboard so I removed the baseboard and undercut the drywall to get the additional space. I used an oscillating multi tool to cut the drywall....shop vac in one hand and tool in the other to get the drywall dust.

I'm a Bay area floor contractor, and a 1/4" gap is standard for this region.

Try installing in a historical property, where you cannot cut or remove the original base and you cannot add "shoe molding"