Dealing with vandalized glass on commercial buildings
February 28, 2014
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July 2, 2015
Construction Damage on Glass
February 25, 2020
Over our nearly twenty-five years in business we have seen too many construction projects with damage to newly installed glass. Finding out which subcontractor is at fault can be a daunting task in itself, much less the repair or replacement of said glass. Even if the glass isn’t that expensive the labor in replacement, painting, lost time and disturbance to a finished area can be a hassle. Here we will offer information for keeping glass damage at bay and what to do about it should it occur.
We’ve often said the best way to handle glass damage is to not get it in the first place. Obvious yes, but it warrants some forethought to keep damage at bay. Here are some of the ways glass can become damaged on the job site:
Welding or grinding of steel Glass must be protected from any kind of sparks that could impact the glass (or any finished surface for that matter). If any welding or grinding of steel is to take place, nearby glass must be covered and protected. Sparks from welding or grinding are essentially small meteorites of molten metal. They will burn their way into the surface of glass and leave the dark bits of cooled metal in the bottom of a pit that can be problematic to completely remove through glass polishing.
Dried concrete, mortar or stucco If splattered concrete, mortar, or stucco is allowed to dry on glass it can be difficult to remove without scratching. Where the material could have been easily removed while wet, when dry attempted scraping of the material from glass would drag the silicates around to scratch the glass. Protection of the glass prior to placing and finishing cement products is a must.
Sandpaper on glass Sanding of wood window frames or finishing stainless steel architectural details next to glass invariably results in the sandpaper touching the glass and cutting into it. This type of damage can be especially problematic because sanding grit is a hard and sharp material very effective at cutting glass. Such damage is usually right at the edge of the glass where polishing and feathering of the polished area is most difficult. Whether sanding by hand or with a power sander the abrasive must not be allowed to touch the glass.
Drywall joint compound or paint removal Inexpert attempts to remove drywall joint compound (taping mud) or paint from the surface of glass can leave the glass scratched. Usually the least experienced personnel will get tasked with the removal attempt which is a problem in itself. We have seen jobs with over $100,000 worth of glass scratched beyond repair in less than a day by a single individual. The use of scrapers, razor blades, abrasive pads, and steel wool by laborers with no idea of the consequences is to be avoided.
Cleaning scratches If some of the above conditions exist or your janitorial service isn’t knowledgeable about such issues it can cause a lot of problems. Any company which touches your project’s glass is only as good as the lowest paid person on their crew. Synthetic scrub pads, steel wool, razor blades, & scrapers used on the glass can put scratches in the surface. Many glass manufacturers don’t clean their production rollers which leave detritus on the surface of glass just before it enters the tempering oven. Once in the oven this material becomes baked into the surface of the glass and even a stainless scraper blade (softer than carbon steel) will drag it across the glass leaving scratches.
Glass vandalism Commercial glass is especially subject to glass vandalism. While we usually treat vandalism as a category separate from construction damage it can occur during construction. The more expensive/ greater lead times to replace said glass the glass the greater the risk to the overall project. Virtually invisible protective films are available as cheap insurance for this kind of damage and can protect against other types of construction related damage.
Preventing, protecting and repairing glass
All project subcontractors should be notified that cleaning, removing masking, or other activities involving the glass must be approved by the general contractor. Drywall finishers, painters, and plasterers especially should be notified and scrutinized.
Temporary protective film for glass & aluminum Some window manufacturers will ship glass out with removable protective film installed. The benefits of this are obvious. If the glass isn’t supplied with protective film it can be installed at the job site on the interior, exterior or both. This can be cheap insurance to prevent glass damage. When the project is at a satisfactory state of completion, the protective film can be removed to leave clean, undamaged glass. Temporary films can be installed on window and door aluminum frames as well to protect them from damage.
Repairing scratched glass Many glazing contractors will tell you that if a scratch can be felt with a fingernail it cannot be removed. This is incorrect and, unless very deep or in an difficult location, scratches on glass can usually be polished out. The shallower the scratches the less time it will take. Very deep scratches or damage where there are chips taken out of the glass can be time consuming, difficult to remove, and possibly not cost effective based on replacement cost of the glass.
Should you find yourself with scratches or other damage in your project’s glass you should seek professional help. At GSR, Inc., we have the knowledge and experience to help you weigh your options to seek a resolution or peremptorily protect the glass. Hopefully you’ll never need our services to remove glass damage, but if you do we’re here to help.