Masonry Magazine March 2001 Page. 16
COVER STORY
FROM GROUND
THE
UP
UP
UP
by George Miller, MCAA Consultant
Scaffolding is one of the more useful and versatile pieces of equipment on a masonry project. It comes in many forms and through the years has developed into an efficient productive tool for mason contractors. Scaffold was created when man needed height to build from the ground up. Rough timber provided the means for workers to extend their work level up, and it took decades for the development of a more refined scaffold. With buildings taking on new configurations and greater heights, scaffolding kept pace with the changing building technology.
In the 17 and 18 hundreds and into the early 19 hundreds, wood remained the main material used for building scaffolds. Some of the more commonly used scaffolding for that time period were:
SINGLE-POLE SCAFFOLDING
Single-pole scaffolding, which consisted of a single row of posts set upright, were less than 5 feet from the building and spaced not more than 7 feet apart. Posts were braced diagonally and connected horizontally with a stringer and ledger members. Putlogs to carry the plank platform were supported on a ledger at the outer end and in a wall recess on the inside. At the completion of the wall the recesses were filled in as the scaffold is removed.
HORSE SCAFFOLDING
Horse scaffolds consisted of trestles or horses 4 to 5 feet high. Scaffold planks were supported on the bearer. This type was limited to 3 tiers of horses or 12 feet in height. Horse scaffolds were used extensively on residential units or light commercial structures.
BUILT-UP SCAFFOLDING
Built-up scaffolding consisted of a double row of posts. The inner row was set as near to the wall as practical. Scaffold planks were placed on bearers with diagonal bracing placed in both directions on the outer row of posts. This, like the single-pole and wooden horses, was limited in height and capacity (see photo 1).
SQUARE SCAFFOLDING
Square scaffolding consisted of framed wood squares or jacks used to support a plank platform in a manner similar to wooden horses. The squares were generally made from 2 by 4's and were not larger that 5 feet on each side. When the squares were placed in position, they were laterally braced by 1 by 6 diagonal bracing, both on the front and back sides of the scaffold.
We must remember that in this early time period, masonry walls were extremely thick since they were the load-bearing structure that made the building possible. Walls up to 36 inches in thickness required different methods of both laying the units and in supplying the vast amount of materials needed for the project.
GILBRETH SCAFFOLDING
Frank B. Gilbreth, an innovative mason contractor in the New England area in the late 18 hundreds, was responsible for building major masonry buildings. In 1902 he completed the Lowell Laboratory of Electrical Engineering at the Massachusetts Institute of Technology in two months and seventeen days. This building covering 44,000 square feet of land was completed 54 days ahead of contract time. Before starting the building, he spent several days