Picking an exterior access solution for your construction project can be a complicated decision to make. Choosing the wrong solution can create logistical, schedule and quality issues. Today we’re going to walk through the different exterior access solutions you have available to you in construction, and some of the advantages and disadvantages of each.
Note that we are writing this from Canada, some of the terminology and techniques we are writing about may be different in your country. Make sure to check with local vendors on solutions they have available to you.
When you start in construction likely one of the first temporary structures you will come in contact with is scaffolding. There are many different types and forms of scaffolding so let’s stick with the “tube and coupler” type which is used throughout North America.
Scaffolding can be defined by its ladder like look from the outside.Scaffolding is a very flexible solution for #construction and can be custom designed for your project by a structural #engineer. Click To Tweet
Scaffolding is the most common access type mainly because of it’s safety and versatility. Scaffolding can provide you consistent (key word here) throughout the entire face of your building at intervals that you define. So if you need a platform every 6’ for 25 people to work off of, scaffolding is your best bet.
One of the other great advantages of scaffolding is the ability to enclose it. It is common practice to enclose the scaffolding in netting preventing tools, debris and dust from falling and hurting or disturbing the surroundings. If netting isn’t enough you can use an insulated tarp and heat the cavity space, or print a graphic on a scrim and hide your scaffolding all other.
One of the main disadvantages to scaffolding is the cost. Typically scaffolding is put up when you need regular acccess to an area for a long duration or an intense short duration. The initial setup, dismantle and engineering costs can be prohibitive.
The weight of scaffolding can also be a deterrent. Depending on the height you need to get to scaffolding can be heavy. Weight can affect the surface you sit it on, so, depending on the structure below you may need additional shoring to support the weight of the scaffolding.
Swing stages are next up one of our personal favourites. Swing stages are commonly seen on high rise towers where window cleaners have to get access to the exterior facade. Swing stages have a strong use in commercial construction as well as they provide a flexible means of accessing the exterior.
Swing stages can be identified by a metal platform that is hung off of the roof by cables (two cables or four). Unlike scaffolding there is no support at the ground level.
This system is advantageous for a few reasons, it is quick to set up allowing workers to be on the side of the building in a relatively fast manner. It allows continuous access to any point along a certain “drop” on a building. Swing stages are also relatively quick moving when you compare them to scaffolding or climbers.
One of the main disadvantages to swing stages is safety. Swing stages require special training and sign off by an engineer. Dealing with less reputable vendors can sometimes jeopardize the quality of the stage and it’s parts potentially putting the workers at risk. Before you start any stage work make sure to check with your local vendors and ensure their industry certifications check out.
Another downside to swing stages is that they are top loaded and difficult to move. The roof system needs to have roof anchors, otherwise large counterweights need to be installed to support the stage. When you need to move the swing stage to another location the stage needs to be relocated manually by a certified vendor / installer.
When you need more capacity and something a little more rigid than a swing stage turning to a self climber system might be the answer for your exterior access needs. If you’ve ever walked by a construction site and seen a platform supported by a large vertical metal mast that is a motorized self climbing system.
The platform is centrally supported by the mast which is attached to the side of the structure. The platform moves up and down the mast by a motor.
Some advantages of a self climbing system are a higher capacity and safer more stable work surface. The platform allows you to put multiple people and material on the same level. Because the platform is relatively stable it is safer for the workers and can integrate guardrails.
One of the down sides to using climbers is the weight on specific points in the strucutre. The brackets attach to beams or columns as it goes up the building and the point loads on those can be high. If you have an older building this may not be a suitable option.
Lifts (Scissor and Boom)
Lifts are one of the most common pieces of equipment on a construction job site and require minimal training to operate. Using a lift on a project jobsite should be one of your first considerations due to their flexibility and relatively inexpensive cost.
Many companies in North America have built businesses on renting out lifts. They can come in many different types, from boom lifts where the arm extends to the height you need. To scissor lifts which provide you with a stable platform and are relatively compact. There are even off road variants and variants that fit through doors.
One of the main advantages to lifts is their ability to reach complex places. They have a strong safety record (as long as they are well maintained) and are relatively inexpensive when you compare them to some of the other options on this list.
Conversely, lifts can get very heavy the higher you need to go with them. Some of the larger lifts (in excess of 50’) may require shoring underneath of them if your substructure is weak. In addition lifts reach can be limited. When you get to some of higher heights their stability is limited and it can be difficult to work off of.
No matter what lifting solution you end up going with on your project it’s important to remember that the safety of your workers should be paramount.
Do you have a vertical access solution that we haven’t listed here? Let us know below or in our social media channels!
Also published on Medium.