Slipform stonemasonry is a method for making a

reinforced concrete Reinforced concrete (RC), also called reinforced cement concrete (RCC) and ferroconcrete, is a composite material in which concrete's relatively low ultimate tensile strength, tensile strength and ductility are compensated for by the inclusion ...

wall with stone facing in which stones and mortar are built up in courses within reusable

slipform Slip forming, continuous poured, continuously formed, or slipform construction is a construction method in which concrete is poured into a continuously moving form.Nawy, ''Concrete Construction Engineering Handbook,'' 2008, p. 10—33. Slip form ...

s. It is a cross between traditional mortared

stone wall Stone walls are a kind of masonry construction that has been used for thousands of years. The first stone walls were constructed by farmers and primitive people by piling loose field stones into a dry stone wall. Later, mortar and plaster ...

and a veneered stone wall. Short forms, up to 60 cm high, are placed on both sides of the wall to serve as a guide for the stone work. The stones are placed inside the forms with the good faces against the form work.

Concrete Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most wid ...

is poured in behind the rocks.

Rebar Rebar (short for reinforcing bar), known when massed as reinforcing steel or reinforcement steel, is a steel bar used as a tension device in reinforced concrete and reinforced masonry structures to strengthen and aid the concrete under tension. ...

is added for strength, to make a wall that is approximately half reinforced concrete and half

stonework Stonemasonry or stonecraft is the creation of buildings, structures, and sculpture using stone as the primary material. It is one of the oldest activities and professions in human history. Many of the long-lasting, ancient shelters, temples, m ...

. The wall can be faced with stone on one side or both sides. After the concrete sets enough to hold the wall together, the forms are "slipped" up to pour the next level. With slipforms it is easy for a novice to build free-standing stone walls.

History

Slipform stonemasonry was developed by New York architect

Ernest Flagg Ernest Flagg (February 6, 1857 – April 10, 1947) was an American architect in the Beaux-Arts style. He was also an advocate for urban reform and architecture's social responsibility. Early life and education Flagg was born in Brooklyn, N ...

in 1920. Flagg built a vertical framework as tall as the wall, then inserted 2x6 or 2x8 planks as forms to guide the stonework. When the masonry work reached the top of a plank, Flagg inserted another one, adding more planks until he reached the top of the wall.

Helen Helen may refer to: People * Helen of Troy, in Greek mythology, the most beautiful woman in the world * Helen (actress) (born 1938), Indian actress * Helen (given name), a given name (including a list of people with the name) Places * Helen, ...

and

Scott Nearing Scott Nearing (August 6, 1883 – August 24, 1983) was an American radical economist, educator, writer, political activist, pacifist, vegetarian and advocate of simple living. Biography Early years Nearing was born in Morris Run, Tioga Coun ...

modified the technique in Vermont in the 1930s, using slipforms that were slipped up the wall.Elpel, Thomas J. Living Homes: Stone Masonry, Log, and Strawbale Construction. HOPS Press, 2010, p. 85.

Gallery

File:Oiled slipforms.jpg, Slipforms oiled to prevent concrete from sticking to the wood. File:Placing Stones in Formwork.jpg, Placing stones inside the forms. File:Window Frame in Stonework.jpg, Window frames are placed in the forms. File:Forms are leap-frogged up the wall.jpg, Slipforms are leap-frogged up the wall. File:Finished Slipform Stone House.jpg, A finished slipform stone house.

Notes

The diagram of the slipform wall section is completely misleading without showing the 2nd form.

External links

Slipform Stone Masonry
{{Stonemasonry Stonemasonry Construction Types of wall