Lift for installing glass façades and windows

For installing glass façades, curtain walls and large window joinery, an articulating or telescopic boom lift (cherry picker, aerial work platform, MEWP) is most often used: the platform reaches over the driveway, entrance, greenery and the base of the building, so the pane is placed against the face of the wall without standing the machine right next to the façade. On level, hard ground at a low façade, and when working straight up, a scissor lift is enough. Three things matter: the installation height, the obstacles at the base of the building, and the weight of a single pane together with the fitters and suction cups on the platform.

Which lift for which façade?

• Articulating boom lift — when the machine cannot stand under the place of installation: over a driveway, steps, greenery, an entrance canopy or a plinth. The platform reaches sideways and “looks” over the obstacle, and models in our fleet have a horizontal outreach of even more than 20 m. It is the most common choice for glazing ground floors and first floors from a distance.
• Telescopic boom lift — for tall façades and the curtain walls of high-rise buildings: a large vertical and horizontal reach with a rigid boom that guides the platform with a heavy pane confidently. In our fleet telescopic boom lifts work up to about 57 m working height, with an outreach of up to about 24 m.
• Scissor lift — for interior glazing, shop windows, atria and low façades where you can drive straight up on level ground. A large, stable platform holds two fitters with a pane and fittings; electric versions do not mark a finished floor.

How do you work out the height and outreach you need?

The working height of a lift is the height of the platform floor plus about 2 m (the arm reach of a standing person). For a façade it is matched to the level of the highest pane or profile to be installed, not to the height of the whole building. The second parameter is horizontal outreach, that is how far the platform reaches horizontally from the chassis. It is counted from the place where the machine will actually stand: behind the paved strip around the building, the driveway, a flower bed or a covered entrance. How to read both values from the machine’s chart is described in the article how to read the load and reach chart.

Platform capacity: fitters, suction cups and a heavy pane

Glass is heavy: an insulated glazing unit weighs about 25–30 kg per square metre, and large façade panes weigh 100–200 kg and more. The platform capacity covers everything at once: people, the vacuum lifter or suction cups, and the pane itself. Articulating and telescopic boom lifts in our fleet have a platform capacity of 200–450 kg depending on the model, so light and medium panes are installed directly from the platform. The largest glazing is lifted separately:

• heavy panes are handled with a crane, a glazing mini crane or a vacuum lifter, and from the platform you only position them in the profile and fix them,
• the pane is not leaned against the guardrails or projected beyond the outline of the platform in such a way that it hits the structure while driving,
• suction cups and the vacuum lifter also count towards the capacity limit: they have to be added to the weight of the people and the pane.

Wind: with glass, it rules

A large pane acts like a sail, which is why with glazing wind matters more than in most work at height. The manual of an aerial work platform gives a permissible working wind speed (in machines from our fleet usually up to about 45 km/h), but installing large panes is carried out in clearly lighter wind, because a gust tears the pane out of your hands and sets the platform swaying. The speed is checked at working height, where it blows harder than near the ground, and in gusts the work is stopped.

Ground, floor and working in an operating building

Boom lifts are heavy, and the load is concentrated under the wheels or outriggers. When working over a garage, on a mezzanine or on a fresh surface, it is worth checking the load capacity (see how much a lift weighs and the floor loading). On finished block paving and floors you work with an electric machine or lay ground protection mats under the wheels; on a muddy site around a building, with a diesel 4×4 machine. The access route is planned to avoid manholes, grilles and fresh screed, and in an operating arcade or atrium the area under the platform is fenced off and the work is done in sections.

Who can work from the lift at a façade?

The operator of a mobile elevating work platform must hold a qualification certificate from the Office of Technical Inspection (UDT), and in the platform of an articulating boom lift a safety harness with a lanyard is required. Façade crews without a licence rent the machine with an operator. For long jobs covering whole façades, long-term rental pays off, and we will choose the machine for the height and the distance from the building: just describe the task.

Frequently asked questions

Which lift should I use to install a glass façade and glazing?

For glass façades and curtain walls an articulating or telescopic boom lift is most often used: the platform reaches over the driveway, entrance, greenery and the base of the building, so a pane can be placed against the face of the wall without standing the machine right next to the façade. On level, hard ground at a low façade, and when working straight up, a scissor lift is enough. The choice depends on the installation height, the obstacles at the base of the building and the weight of a single pane.

How much does a pane of glass weigh and will the lift’s capacity carry it?

Insulated glazing weighs about 25–30 kg per square metre for a typical unit with two air chambers (triple glazing), and with large façade panes a single element is often 100–200 kg and more. Platform capacity counts everything together: two fitters, suction cups or a vacuum lifter, and the pane itself. For articulating and telescopic boom lifts in our fleet the platform capacity is 200–450 kg depending on the model (the most, 450 kg, on the JLG 1250AJP and 1350SJP), so light and medium panes are installed from the platform; the largest glazing is lifted separately (with a crane, a glazing mini crane or a vacuum lifter), and from the platform it is only positioned and fixed.

Up to what wind speed can I install glass from a lift?

A large pane of glass acts like a sail, which is why with glazing wind matters more than in most work at height. Aerial work platforms have a permissible working wind speed in the manual (for lifts in our fleet this is usually up to about 45 km/h, or 12.5 m/s), but installing large panes is safely done in much lighter wind, because a gust tears the pane out of your hands and sets the platform swaying. Wind speed is checked at working height (it blows harder higher up), and in stronger gusts work is stopped.

Electric or diesel lift for installing windows and façades?

On a finished surface (block paving, slabs, a floor in an atrium or arcade) an electric lift is chosen: it produces no exhaust fumes and does not mark. On an unsurfaced, muddy site around a building under construction a diesel 4×4 lift works, as it copes with rough terrain. For glazing interior atria, stairwell glazing and rooflights electric machines are always used.

Do I need UDT licences to install façades from a lift?

Yes. The operator of a mobile elevating work platform must hold a qualification certificate from the Office of Technical Inspection (UDT), and in the platform of an articulating boom lift a safety harness with a lanyard is required. A façade crew without a licence can send an employee on a UDT course or ask about rental with an operator; this is possible when one of our service technicians qualified as an operator is free on that date.