Parts of a Retaining Wall – Labeled Section Diagram

All 15 parts on the diagram

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The concrete wall 4

Stem The vertical slab of reinforced concrete that holds the soil back. It stands on the footing, and the two together often make an upside-down T.
Footing A wide concrete base under the stem. The push of the soil on the stem is passed to it, and it presses down on the ground below.
Toe The part of the footing reaching out in front of the stem. The wall presses on the ground hardest here.
Weep holes Holes or short pipes through the bottom of the wall. They run in a row along it and let out water that collects in the soil behind.

The block wall 4

Wall units (blocks) Concrete blocks laid dry, with no mortar. Each course sits a little farther back than the one below.
Cap units The last course: units made to finish the top of the wall.
Batter (setback) The backward lean of the wall's face. It is made by stepping each course back. Leaning toward the soil makes the wall more stable.
Leveling pad A level bed of compacted gravel or lean concrete. The first course of blocks is set on it. The first course sits below ground level.

Drainage 3

Drain pipe A pipe with holes in it at the foot of the wall. It collects the water that comes down through the stone and leads it away.
Drainage aggregate (wall rock) Crushed stone placed behind the blocks, and in their hollow cores. Water runs down through it easily to the drain pipe.
Filter fabric A cloth that lets water through but holds soil back. The soil then does not wash into the stone and clog it.

Soil and reinforcement 4

Backfill Soil placed and packed down behind the wall once it is up. Water trapped in it adds to the push on the wall, which is why walls are drained.
Geogrid Sheets of strong plastic mesh. Each layer is laid between two courses of block and runs back into the soil, tying the blocks and the soil into one heavy mass.
Reinforced soil The soil packed down in layers between the sheets of geogrid. Builders also call it the infill.
Retained soil The ground behind the reinforced soil. The wall and its reinforced soil together hold it in place.

How this list was compiled: Part names checked on 2026-09-30, a name kept only when two independent sources use it. (1) G. Paaswell, Retaining Walls: Their Design and Construction (1920), full text at https://archive.org/details/cu31924015698016 (stem, footing, toe, heel, weep holes and the broken stone behind them, batter, coping). (2) Federal Highway Administration, Design and Construction of Mechanically Stabilized Earth Walls and Reinforced Soil Slopes, FHWA-NHI-10-024 (2009), https://www.fhwa.dot.gov/engineering/geotech/pubs/nhi10024/nhi10024.pdf (leveling pad, modular block wall units, cap units, batter, geogrid, reinforced fill, retained backfill, drainage aggregate, geotextile filter, drain pipe, weep holes, toe of the footing, backfill). (3) A block maker's installation manual for segmental retaining walls, full text at https://archive.org/details/manualzilla-id-6860810 (base material and leveling pad, base course, blocks, caps, setback and batter, wall rock, drain pipe and toe drain, filter fabric, geogrid, infill soils, retained soil, finished grade). (4) Wikipedia, Retaining wall and Geogrid (stem and footing of a cantilevered wall, batter or setback, segmental concrete units, retained soil, drainage behind the wall; geogrid as a material strong in tension that reinforces soil). (5) W. Cain, Practical Designing of Retaining Walls (1914), https://archive.org/details/practicaldesign00caingoog (weep holes, toe). Licence: own work

The drawing: Drawn for this site on 2026-09-30 from plain geometry; a teaching section, not a design, nothing traced. Licence: own work

How it works

The parts of a retaining wall depend on how it is built, so this page cuts through two: a concrete cantilever wall and a wall of stacked blocks. Both hold higher ground on the right.

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Two ways to hold back soil

The concrete wall is a stem on a wide footing; the soil pushes on the stem and the footing resists. Weep holes let water out. The block wall works by weight: wall units stacked with a batter on a leveling pad, with layers of geogrid tying them to the reinforced soil behind. Drainage aggregate, filter fabric and a drain pipe keep water from building up.

Water is the common thread: both walls give it a way out, because trapped water adds to the push on a wall.
These are teaching drawings. A real wall is built from an engineer's plan.

Questions and answers

What are the parts of a retaining wall called?

On a concrete cantilever wall: the stem, the footing with its toe, weep holes and backfill. On a segmental block wall: a leveling pad, wall units, cap units, drainage aggregate, a drain pipe, filter fabric, geogrid, reinforced soil and the retained soil behind.

What is the toe of a retaining wall?

The part of the footing that sticks out in front of the stem, on the low side. The wall bears on the ground hardest at the toe.

What are weep holes in a retaining wall for?

They let water out. Water that collects in the soil behind a wall and cannot drain away adds its own pressure to the push of the soil, so walls are given weep holes or a drain pipe.

What does geogrid do in a retaining wall?

Geogrid is a plastic mesh that is strong when pulled. Layers of it run from between the block courses back into the soil, so the blocks and the reinforced soil act together as one wide, heavy mass.

What is batter on a retaining wall?

The backward lean of the wall's face. On a block wall it comes from setting each course back a little from the one below. Leaning back toward the retained soil improves the wall's stability.