TSS is by far one of the most expensive height access methods for window cleaning. It requires not only erection of pedestrian protection bridge around the building, which is expensive by itself, but also riggers service for installation of roof rig and its re-setup for each drop. This method is very rarely used for window cleaning due to its complexity, cost, liability and possible roof waterproofing damages.
Its not as productive, versatile and easy to use as a BMU, but does provide safe and 100% legal access to most, if not all areas of a building’s façade. Use of DDS also requires work crew familiarization with equipment and carries maintenance costs.
ADVANTAGES OF TSS
THINGS TO CONSIDER
- As mentioned above, most of the time, the use of TSS for window cleaning is not economically feasible.
- Pedestrian protection bridge is required around the building.
- Roof waterproof membrane might be damaged in the process of rigging.
- Roof rig must be moved by qualified rigger for each drop. Extra cost.
- Certified rigger must be present on a roof each day to inspect the roof rig set up (add $1,100-1,200 per day for the project duration)
- Since time is needed for system set up for each drop, productivity of crew working from TSS is lower compared to the productivity from BMU, RDS or aerial lifts, hence higher in cost. In addition, work crew access is limited to one drop surface area during the drop.