Replacing Railroad Ties with Stone: Choosing the Right Material
Railroad tie walls fail because the wood rots where it sits against wet soil, and the anchors buried behind the wall rot with it. When you replace one, the three usual choices are segmental concrete block, natural stone and boulders. Block is the most predictable and the easiest to engineer for a taller wall. Natural stone gives the most traditional New England look but takes the most skilled labor. Boulders suit long, rough slopes where there is room for big stones and the machine that sets them.
The right one depends on how tall the wall is, what sits above it, how much of your yard the new wall can take up, and how a machine gets to it. This guide walks through each.
Why railroad tie walls fail
Railroad ties were cheap and heavy, which is why so many North Shore yards have them. They were never meant to last forever in the ground:
- Rot from the back and bottom. The face of a tie can look fine while the side touching damp soil has gone soft. Rot usually starts in the lowest courses and in the "deadmen," ties laid back into the slope to anchor the wall.
- No drainage. Many tie walls were built with soil packed straight against the wood. Water held behind the wall keeps the ties wet and adds pressure, and Massachusetts freeze and thaw cycles work that water into every gap.
- Creosote. Old ties were usually treated with creosote, a coal tar preservative. The U.S. EPA advises never burning creosote-treated wood around the home (EPA, Creosote, updated December 2025), and cost guides advise keeping it away from vegetable gardens and play areas (HomeGuide, 2026). For many owners that is reason enough not to rebuild in ties.
Once a tie wall is leaning, bulging or shedding soil through the gaps, patching single ties rarely holds for long. That is the point where people start looking at stone.
Block, natural stone and boulders compared
| Segmental concrete block | Natural stone | Boulders | |
|---|---|---|---|
| How it holds the soil | Weight of stacked units, plus geogrid layers in the soil on taller walls | Weight and interlock of the stones, dry-laid or set in mortar | Sheer weight of very large stones |
| Look | Uniform, even courses; many colors and faces | Traditional and varied; fieldstone or split granite | Rugged and natural; large gaps between stones |
| Fits best | Straight or curved walls, taller walls, walls near driveways, tight lots | Older homes, gardens, walls that are seen up close | Long banks and wooded or rough slopes with room to work |
| Space it takes | Modest footprint; reinforced walls need room behind for the grid | Thicker than a tie wall, especially dry-laid | The deepest footprint of the three |
| Watch-outs | Ask about freeze-thaw rating near salted surfaces | Labor-heavy; mortared walls need a solid footing and drainage through the wall | Needs machine access; hard to build tight corners or crisp steps |
For published price ranges for each material, see our guide to the cost to replace a railroad tie retaining wall.
Segmental concrete block
Segmental retaining wall block is a dry-stacked concrete unit made for walls. Each course sets back slightly from the one below and locks to it with a lip, pins or the shape of the block. Shorter walls stand on the weight of the block alone. Taller walls are usually built as reinforced walls, with layers of geogrid, a plastic mesh, laid between courses and extending back into compacted soil, following an engineered design.
What matters for a Massachusetts wall:
- Freeze-thaw durability. Segmental units are made to a standard, ASTM C1372, that includes freeze-thaw durability requirements where walls can freeze while wet (Concrete Masonry and Hardscapes Association, SRW units, 2026).
- Road salt. The same industry guidance says that if units will be regularly exposed to deicing salts, testing in salt water should be considered, though no pass/fail standard exists for that test yet (CMHA). If the wall lines a driveway or a salted walk, ask the supplier what the block has been tested for.
- Predictable engineering. Block manufacturers publish design and installation guides, which makes block the easiest material to engineer when a wall is tall or holds up a driveway.
Block is the practical choice when the old tie wall was tall, sits on a tight lot, or needs a clean, even face.
Natural stone
Natural stone walls come in two kinds. A dry-laid (dry-stacked) wall uses no mortar; the stones are fitted so they lock together and lean back into the slope, and water drains through the joints. A mortared wall is set in mortar on a concrete footing, which gives a tighter, more formal face but needs designed drainage through or behind the wall so water can't build up.
Stone is the material most North Shore homes already have somewhere, in old fieldstone boundary walls or granite steps and curbing. Cape Ann in particular has a long history with granite: its quarries were shipping stone to Boston, New York, Philadelphia and New Orleans in the 1800s (Harper's New Monthly Magazine, 1884, via Quarries and Beyond). A stone wall often looks at home next to that kind of older work in a way block can't match.
The trade-offs are labor and space. Every stone is fitted by hand, so stone costs more to build than block of the same size, and a dry-laid wall needs to be thicker at the base than a tie wall to hold the same slope. For walls that are tall or carry a load, a natural stone wall still needs a proper design, not just skill.
Boulders
A boulder wall uses stones large enough that a machine sets each one. It suits a long, rough bank, a wooded lot or the edge of a lawn where a rugged look fits and there is room for the stones' depth.
Boulders need a clear path for an excavator and the space to set stones that are much deeper than a tie wall is thick. They don't make tight corners, crisp steps or a flat top for sitting, and the gaps between stones are often planted or filled with smaller stone. On a small or tight lot, block or natural stone usually works better.
What decides the choice on your property
Work through these questions before choosing a material:
- How tall is the new wall, measured from the bottom of the footing? In Massachusetts a retaining wall over four feet from the bottom of the footing, or any wall supporting a surcharge such as a driveway, needs a building permit (780 CMR, R105.2). Taller and loaded walls push you toward an engineered block wall or an engineered stone design.
- What is above it? A driveway, parking area, patio or house near the top adds load. That is engineering territory whatever the material.
- How much yard can the new wall take? Ties are only 6 to 8 inches thick (HomeGuide). Stone and boulder walls are thicker, and reinforced block needs grid behind it, so the new wall may have to sit further out or cut further into the slope.
- Can a machine reach it? Boulders need an excavator. Block and stone can be moved in smaller loads, but tight access adds labor to any material.
- Is it near salt or water? Walls beside a salted driveway or exposed to coastal spray on Cape Ann should use materials that hold up to salt; ask about testing for block, and choose dense stone.
- What matches the house? On an older home with existing fieldstone or granite, natural stone often blends in. On a newer home or a crisp, modern yard, block can look more at home.
If the new wall is on a hillside rather than a simple one-step bank, our guide to building a retaining wall on a slope covers terracing and stepping the base.
Taking out the old ties safely
Removing a tie wall is part of the job, and it has its own rules:
- Disposal. Treated and untreated wood are banned from Massachusetts landfills (MassDEP waste disposal bans), so old ties go to a facility that accepts wood waste. Ask your hauler or town transfer station where they go locally. Never burn them (EPA).
- Utilities. Massachusetts law requires notifying Dig Safe (811) at least 72 hours before digging, not counting weekends and holidays (Dig Safe law, M.G.L. c. 82, s. 40).
- Loaded walls. If the wall is tall or holds up a driveway, path or building, don't pull the face off yourself. The soil behind it can move once the ties come out. Have a professional plan the removal and the new wall together.
George Hardscaping builds retaining walls in stone, rock, brick and concrete across Gloucester and the North Shore, as part of its wider hardscaping and masonry work. It also handles excavation, so clearing out an old wall and preparing the ground can be one project. To talk about replacing a railroad tie wall, request an estimate or call (781) 222-0805.
