There are usually no local codes that prescribe tile installation methods. There are however very clear and precise recommendations from The Tile Council of North America. What I see there ain't them.

You NEVER grout tile tightly to a wall or baseboard, NEVER. The tile should be under the baseboard with a 1/4" gap at all walls for expansion. The baseboard covers the gap, expansion is available, and the tile won't explode or erupt over time.
