What are the key considerations and issues to be identified when it comes to maintaining various types of façades, and what new technologies are available to make this easier and more cost-effective? HARTLEY HENDERSON investigates.
As buildings grow taller and more valuable, there is an increasing need to ensure that façades are properly cleaned and maintained. While building managers often develop maintenance plans for internal plant and property, external façade elements, which are often inaccessible, are generally neglected.
Poorly maintained façades present an unattractive image and dirty windows can annoy building occupants. This, in turn, can have a negative impact on building values and rental returns for building owners.
KNOWING WHAT MAINTENANCE IS REQUIRED
Although the Building Code of Australia requires buildings over three storeys to have a system that allows for the cleaning of windows and routine maintenance, one of the biggest problems in strata residential works is the lack of common property rooftop access to the external façade or poorly designed height safety systems. This is according to Steven Gates, managing director of BaseFX, a work-at-heights company specialising in a wide range of building cleaning and maintenance services.
“It is challenging for building managers to identify problems arising in a building over three storeys, simply due to lack of access and inability to inspect,” he says. One way to overcome this issue is through equipping abseil access teams with cameras and defect boards during window cleaning works, so that they can photograph and log potential maintenance needs, Gates notes.
“A façade defect report for substantial matters can then be provided to the building manager, which might include evidence of cracking, spalling, render delamination, expansion joint failure and steel rusting or corrosion. Areas that may be seen from the ground signifying a deeper issue include rust staining or leaching, calcium staining or build-up, weeds or moss growing on façades, water leaks and paint blisters.”
Gates states that every new building element is covered by a manufacturer’s or installer’s warranty, typically for five to 25 years, and that, commonly, these warranties require periodic cleaning to be conducted otherwise the warranty may be voided in full or part.
“Importantly, building managers need to understand what warranty cleaning requirements exist for their building, which may determine the cleaning methods and frequency. Life cycle forecasts should be aligned to capital works and sinking funds,” Gates notes. “All façade elements have a finite life and deteriorate or break over time, so building managers need to ensure budget allocations for both expected repairs and programmed maintenance.”
THE HIGH COST OF DEFERRING FACADE MAINTENANCE
According to Gates, façades should be soft or pressure washed every one to five years, depending on location. Numerous issues arise from a lack of façade maintenance, which is often a result of insufficient budget allocation.
“Inadequate budget allocation can lead to problems, due to a decrease in service that can result in additional costs in coming years. This can relate to factors such as lack of louvre lubrication, bird damage to façade elements, inadequate cleaning frequency, paint pigment staining to façades and windows, and inappropriate façade materials,” Gates explains.
“It should also be recognised that windows on buildings develop staining over time that cannot be removed by normal window cleaning. This staining is caused by water leaching mineral deposits forming a mist line or shadow. Where this occurs, glass will require costly rejuvenation or replacement, which could have been prevented by increasing the cleaning frequency.”
In addition, when cleaning windows on a neglected façade, black marks under windows can be caused by a boot, hand or knee scuffing over dirt and pollution accumulation on the façade, adds Gates.
A further problem relates to painted surfaces that break down over time and leach paint pigments down the façade or windows. By deferring repainting, additional costs can be incurred through expensive window rejuvenation using buffers to cut back the glass, warns Gates.
Gates also points out that the incorrect choice of maintenance method, system or product can lead to wasted money or additional costs. He believes a clear distinction should be drawn between programmed preventative maintenance and reactive maintenance.
Jan Kroupa, managing director of Safetek, which provides a range of façade cleaning and maintenance services, states that different maintenance levels need to be considered depending on the location of the property. “Factors such as smog and pollution, humidity and salt in the air have to be taken into account when designing a maintenance program,” he notes.
Gates agrees, adding that adjustable louvre panels in a salt environment will corrode and seize up within five years unless regularly washed and lubricated. “We see clients where no maintenance has been carried out and within five years 80 percent of louvres have broken louvre blades, central pivot handles do not work, or the louvre blades cannot be adjusted in pitch,” Gates notes.
In addition, building managers also need to understand what types of birds frequent a building’s area, and what damage they may be doing. Gates provides the example of cockatoos in Sydney, which will rip out façade expansion joints, rubber and paint.
Kroupa states that maintenance instructions vary depending on the manufacturer, but typically painted surfaces require a yearly wash down, windows need to be cleaned every six months, and aluminium components, such as window frames or external blinds, should be cleaned every six to 12 months.
NEW TRENDS IN FACADE MAINTENANCE
Gates advises that traditional façade access methods utilising scaffold, swing stages and hoardings are being replaced by highly skilled rope access teams where the cost of the remedial works for, say, painting is now less than the cost of just erecting a scaffold.
“Industrial rope access provides a safe, cost-effective and efficient means of accessing buildings and structures for inspection, cleaning and maintenance. It offers an answer to accessing areas that in the past would have been considered inaccessible or would have taken an enormous amount of planning and resources to execute,” Kroupa notes.
Kroupa advises that building managers and owners should use the services of a reputable rope access company to help them develop a scheduled maintenance program tailored to their building. “Different buildings will have different problems. For example, non-porous materials like glass, Apolic panels and marble will develop different problems to a concrete façade,” he states.
Other new developments in façade maintenance reported by Gates are pure water or de-ionised (DI) water systems and laser scanning of buildings. “Pure water or de-ionised water systems are starting to show a presence in the high rise markets. DI systems use a highly filtered water to remove 99 percent of contaminants, which would leave a residue on drying. With DI systems, windows and frames are washed rather than using traditional mitts and squeegees,” he imparts.
“Laser scanning of buildings can be used to undertake multiple tasks by creating 3D modelling of buildings, determining measurement bench marks and for determining movement in façades or components. These systems are point-of-sight and limitations exist for any façade areas not in direct point-of-sight, so they are potentially inadequate for high-rise buildings. Some of these systems have, however, been useful in detecting bowing in granite façade panelling,” Gates notes.
A further development that is set to make façade maintenance easier and more cost-effective is self-cleaning glass. Self-cleaning glass can be especially useful for inaccessible windows, windows that are unsafe to clean and areas where organic dirt collects, such as roof lights.
One example is Australian glass manufacturer CSR Viridian’s Renew, which has a specially developed hydrophilic transparent exterior coating. According to the company’s marketing manager, Lachlan Austin, once exposed to daylight the coating reacts with UV rays to break down organic dirt deposits, such as bird droppings and tree sap, providing improvements to the amenity, environmental impact and operating costs of a building.
“When water hits the glass, the hydrophilic quality of the glass assists in washing dirt away and reduces the occurrence of spots and streaks. It is particularly effective in regions and applications where glass has a high exposure to sunlight and rainfall. The glass performs better with water running uniformly rather than selectively over the glass,” Austin says.
He notes that Renew will not, however, self-clean non-organic deposits such as salt and calcium, thus care should be taken when specifying this glass in high salt environments such as beachside locations, as it can be unlikely to perform as intended in these conditions.
ENSURING FACADE ACCESS DURING DESIGN
The design of a building plays a vital role in its functionality, as well as its maintenance. According to Kroupa, it is becoming more common for architects and builders to consult with façade maintenance companies such as rope access companies. “It is inevitable that this will become common practice, as smart design can save tens of thousands of dollars on yearly maintenance,” he says.
“Unfortunately, it appears that some architects still design buildings only according to what they think looks good on paper, but even the most beautiful structure made of glass and polished stainless steel will look grubby after a few years if access to its façade is limited or impossible.”
