On new construction, tubular scaffolding is efficient up to 60' high or five stories. Above this it is usually better to use a hung scaffolding if construction permits. Swing scaffolding operations may interfere with tenants. In this case, the tubular is more practical at all heights.
In repairing or cleaning the front of an existing building, the cost of tubular scaffolding per SF of building front increases as the height increases above the first tier. The first tier cost is relatively high due to leveling and alignment.
The minimum efficient crew for erecting and dismantling is three workers. They can set up and remove 18 frame sections per day up to five stories high. For six to twelve stories high, a crew of four is more efficient. Use two or more on top and two on the bottom for handing up or hoisting. They can also set up and remove 18 frame sections per day. At 7' horizontal spacing, this will run about 800 SF per day of erecting and dismantling. Time for placing and removing planks must be added to the above. A crew of three can place and remove 72 planks per day up to five stories. For over five stories, a crew of four can place and remove 80 planks per day.
For jobs under 25 frames, add 50% to rental cost. Rental rates will be lower for jobs over three months’ duration. Large quantities for long periods can reduce rental rates by 20%.
Scaffolding is often used as falsework over 15' high during construction of cast-in-place concrete beams and slabs. Two foot wide scaffolding is generally used for heavy beam construction. The span between frames depends on the load to be carried with a maximum span of 5'. Heavy duty shoring frames can be spaced up to 10' OC depending on form support design and loading.
Scaffolding used as horizontal shoring requires less than half the material required with conventional shoring. On new construction, erection is done by carpenters.
Rolling towers supporting horizontal shores can reduce labor and speed the job. For maintenance work, catwalks with spans up to 70' can be supported by the rolling towers.
For more on scaffolding, check out RSMeans Building Construction Cost Data.