Snecked rubble is a method of constructing a strong masonry wall using differently sized stones laid in a pattern. There are three stone types used - the riser, leveller, and sneck - with specific height ratios. Stones are laid following bonding rules, starting with a riser and three levellers and filling gaps with a sneck, riser, and two levellers. This pattern is repeated to build the wall up. Snecked rubble walls can be built as cavity walls, solid walls, or composite walls.

1. Snecked Rubble
Introduction for Stonemasons
Stonemasonry Department 2012

2. Introduction
“(Snecked Rubble)...is a method of
building an incredibly strong
masonry wall with differently sized,
(and even very loosely squared),
stones, in either ashlar or rubble
work, with a pattern that is both
handsome and, at the higher levels
of workmanship, artistic.”
Bobby Watt

3. Stone Identification
Riser Leveller Sneck
There are three stones used to construct snecked rubble. These are
known as the riser, the leveller and the sneck. The combined height of
the leveller and sneck must equal the height of the riser and the bed
height of each stone is constant.

4. Dimension Ratios
Riser: Height must equal the combined heights
of leveller and sneck plus the thickness of the
bed. Length is approximately twice the height.
Leveller: Height is approximately two thirds of
the riser. The length is approximately three
times the height.
Sneck: Height equals the difference between the
height of the riser and the height of the leveller
less the thickness of the bed. Length is about
three times the height.

5. Bonding Pattern
The three stones are constructed in a bonding pattern which is
governed by a set of strict rules.
= Foundation = Sneck
= Riser = Leveller

6. Bonding Pattern
The wall is started by building a riser followed by three levellers. This
combination is repeated for the full length of the wall.
= Foundation = Sneck
= Riser = Leveller

7. Bonding Pattern
The gaps between the risers are filled with a sneck, then a riser, then
two levellers.
= Foundation = Sneck
= Riser = Leveller

8. Bonding Pattern
The gaps between the new risers are also filled with a sneck, a riser,
and two levellers.
= Foundation = Sneck
= Riser = Leveller

9. Bonding Pattern
This pattern is repeated until the wall reaches its finished height.
= Foundation = Sneck
= Riser = Leveller

10. Heads to a Joint
There are a maximum of three heads to one joint.

11. Riser Formation
The risers should be positioned to form a rough diamond pattern
throughout the wall.
= Foundation = Sneck
= Riser = Leveller

12. Maximum Bed Length
The horizontal bed should not exceed the combined lengths of two
levellers, one riser and one sneck
= Foundation = Sneck
= Riser = Leveller

13. Alternative Patterns
It should be noted that there are alternative bonding patterns for
snecked rubble. Provided the pattern follows the rules, it is acceptable.
= Foundation = Sneck
= Riser = Leveller

14. Common Construction Methods
Cavity Wall Construction
This form of construction generally has an
outer leaf of stone and an inner leaf of brick
or concrete block separated by a cavity
(airspace) of approximately 50mm.
Wall ties are placed in a diamond pattern
with five ties per square metre to hold the
leafs together.

15. Common Construction Methods
Solid Wall Construction
This form of construction has stone on both
sides of the wall and uses through stones
(one every square metre) to bond the wall.
This is a very stable method of construction
but is more expensive than other common
methods due to the increased quantity of
stone required.

16. Common Construction Methods
Solid Composite Wall Construction
This form of construction consists of an
outer facing of stone and an inner backing
of brick, block or concrete. The wall is
bonded by the incorporation of bonder
stones positioned at least one per square
metre.

17. Image References
The image on the “Introduction” slide of this presentation
was sourced from
http://www.rjwstonemasons.com/documents/pictures.htm
The image on the “Introduction” slide of this presentation
was sourced from
http://www.rjwstonemasons.com/documents/pictures.htm

18. Developed by The Stonemasonry Department
City of Glasgow College
2012