Complete Dry Stone Wall Construction: From Field to Fence
Dry stone walls use no mortar, relying entirely on the skill of the builder and the weight of the stone. This campaign covers stone selection, wall anatomy, building technique, and structural principles.
Chapter 1: Wall Types
Type
Height
Width (base)
Purpose
Difficulty
Single wall (garden)
2-3 feet
12-18 inches
Garden border, raised bed
Low
Double wall (field)
3-5 feet
24-36 inches
Livestock fence, property boundary
Moderate
Retaining wall
2-6 feet
18-36 inches
Hold back earth on slopes
Moderate-high
Ha-ha (sunken fence)
3-4 feet (below grade)
24-30 inches
Invisible livestock barrier
High
Building wall (structural)
6-10 feet
36-48 inches
Load-bearing building wall
Very high
Chapter 2: Wall Anatomy
Component
Location
Purpose
Stone Type
Foundation stones
Below ground, in trench
Stable base, prevent settling
Largest, flattest stones
Through stones (tie stones)
Span full wall width
Tie two faces together
Long stones, full wall width
Face stones
Outer surfaces (both sides)
Visible wall face, weather protection
Flat faces, uniform size
Hearting (fill)
Between two faces
Fill void, add weight
Small, irregular stones
Cope stones (cap)
Top of wall
Protect wall top, add weight
Heavy, flat, or upright stones
Batter
Wall narrows from base to top
Stability (gravity pulls inward)
N/A (design feature)
Chapter 3: Building Technique
Double wall construction: 1) Dig foundation trench 6-8 inches deep, width of wall base. 2) Lay foundation stones (largest, flattest stones, level). 3) Set string lines for both faces (guides for straight, plumb walls). 4) Build two parallel faces simultaneously. 5) Each stone bridges the joint below (one over two rule). 6) Tilt each stone slightly inward (toward center of wall). 7) Fill center (hearting) with small stones as you build each course. 8) Place through stones every 3-4 feet horizontally, every 2-3 courses vertically. 9) Through stones span the full wall width, tying both faces together. 10) Maintain batter: wall narrows from base to top (1 inch per foot of height). 11) Cap with cope stones (heavy stones on top, mortared if desired).
Principle
Rule
Why
One over two
Each stone spans the joint between two stones below
Prevents vertical crack lines
Tilt inward
Stones slope slightly toward wall center
Gravity holds wall together
Through stones
Full-width stones every 3-4 feet
Ties two faces into one structure
Batter
Wall narrows 1 inch per foot of height
Creates inward lean for stability
Hearting
Pack center tightly with small stones
Adds mass, prevents face stones from pushing inward
Level courses
Keep courses roughly level
Even weight distribution
Chapter 4: Stone Selection and Shaping
Stone Type
Workability
Availability
Durability
Best For
Limestone
Easy to shape
Common
Very good
All wall types
Sandstone
Easy to shape
Common
Good
All wall types
Granite
Difficult to shape
Common
Excellent
Foundations, heavy walls
Slate/schist
Splits into flat pieces
Regional
Good
Flat-coursed walls
Fieldstone (mixed)
Variable
Very common
Variable
Rustic walls
Stone shaping tools: 1) Stone hammer (2-4 lbs): rough shaping, breaking. 2) Pitching tool: removes large bumps from face. 3) Point chisel: detailed shaping. 4) Flat chisel: creating flat surfaces. 5) Trace (wide chisel): splitting along grain. 6) Most dry stone walls use minimally shaped stone (skill is in selection and placement).
Chapter 5: Structural Principles
Failure Mode
Cause
Prevention
Bulging
Face stones pushed outward by hearting
Tilt stones inward, use through stones
Toppling
Wind, animal pressure, no batter
Maintain batter, heavy cope stones
Settlement
Poor foundation, soft ground
Dig to firm soil, use large foundation stones
Frost heave
Water freezes in wall, expands
Good drainage at base, avoid trapping water
Running joints
Vertical joints align across courses
Follow one-over-two rule strictly
Reference Card
One over two, two over one (every stone must bridge the joint between the stones below it; this is the fundamental rule of all stone and brick construction). 2. Through stones tie the wall together (long stones that span the full width of the wall connect both faces into a single structure; without them, the wall is two separate faces that will separate). 3. Batter creates stability (a wall that narrows from base to top leans inward under its own weight; this inward lean resists toppling from wind and animal pressure). 4. Tilt every stone inward (each stone should slope slightly toward the center of the wall; outward-tilting stones are pushed out by the weight above them). 5. Pack the hearting tight (the small stones filling the center of the wall add mass and prevent face stones from being pushed inward; loose hearting leads to bulging). 6. The foundation is underground (dig a trench and lay the largest, flattest stones below grade; a wall built on the surface will settle and lean). 7. Cope stones protect the wall (heavy stones on top prevent rain from entering the wall core and add weight that holds the wall together; they are the most important course). 8. A well-built dry stone wall lasts centuries (walls in Britain and Ireland built 200-500 years ago still stand; the technique is proven and the material is permanent).
