Batter
Also called: wall batter, batter angle, setback, block setback, retaining wall lean, battered wall
The backward lean of a retaining wall into the soil it holds, set course by course — typically 1/2 to 1 inch of setback per course in block, or 1 inch per foot of height overall. Segmental blocks build it in with a lip or pins; a wall with none, or leaning forward, is moving.
A retaining wall built plumb has all of its weight over its base and none of it working against the soil pushing on it. Battered — leaned back — the wall’s center of gravity shifts into the hill, and the push of the soil has to lift the wall before it can tip it. On a dry-stacked wall that’s a large share of what holds it; on a mortared or poured wall it’s a safety margin the engineer adds. Timber walls are battered by setting each course back an inch; boulder walls by how they’re stacked; segmental block by the block itself — a rear lip that catches the course below, or pins in offset holes, that set 3/4 to 1 inch of setback per course whether the builder thinks about it or not.
The batter is also the first thing a good contractor or an inspector checks on a finished or an aging wall. A 4-foot level held on the face should show a consistent lean back along the whole run. A section that’s plumb where the rest leans, a bulge in the middle courses, or a wall that’s started to lean forward means the soil behind it is saturated and pushing, and the drainage — not the lean — is the fix. Batter buys margin; it doesn’t replace the gravel and the pipe.
A practical consequence for layout: a battered wall’s top is set back from its base by the batter times the height — 4 inches or so on a 4-foot wall — so the base goes that much farther forward than where you want the cap. The DIY guide sets the line at the base for that reason.