Horizontal lap settles a house into its lot; vertical board-and-batten lifts it. Lap flatters long, low elevations and reads familiar on almost any street. Board-and-batten reads taller and more crafted — strong on gables and farmhouse-leaning fronts, and capable of fighting the proportions of a low ranch if it is used wall-to-wall.
The study’s finding is that the mix is usually the answer: lap for the field, batten for the gables and entry bay, and trim proportion doing the quiet work between them.