Volume 38, Issue 11, November 2003
Site Protection of Architectural Glass
Industry Publishes New Reference Document
Architectural glass products used in windows, doors and skylights for today’s residential and commercial building projects are more sophisticated than those used in earlier fenestration applications. Performance re-quirements call for glass to be coated and insulating in order to be more energy efficient; and often heat-treated and laminated to provide greater strength, safety and security. As a result of increased performance capabilities, more glass is being used in both residential and commercial construction. The higher valued products have increased the importance of proper site storage, handling, installation and protection throughout the construction process.
Site Delivery and Storage
During glass manufacturing, fabrication and installation, products are handled carefully to prevent surface and edge damage. Materials are packaged to provide protection during shipment and delivery. Once finished materials are placed on a construction site, they become exposed to a variety of conditions and influences that can affect product aesthetics and functionality adversely. Irreparable glass damage can occur from improper storage and handling, exposure to chemicals and leaching agents, prolonged exposure to moisture, mechanical attack and breakage, damage related to adjacent construction activities and improper cleaning methods.
Windows, doors and skylights for residential construction typically arrive on construction sites preglazed, while commercial construction applications often require that individual lites of glass be delivered to the site and glazed at a later date. In both types of construction, it is vital that materials be stored properly. The complex nature of construction projects and site management require well-planned and executed material delivery and storage. The following is a list of recommended practices for site delivery and storage of fenestration materials:
Glass and glazing system suppliers should be consulted for specific recommendations on the site storage, handling, installation and protection of their materials before any work is started;
• To the extent that it’s practical, glass deliveries should be coordinated to minimize on-site storage durations;
• Subcontractors should work with the general contractor or builder to select on-site, under-roof storage locations that avoid direct rain and water runoff; work areas of other trades; areas of high traffic; and to minimize material movement and handling;
• Individual cases of glass and preglazed materials should be secured, blocked and braced to prevent falls;
• Blocks or supports should ensure that the bottom edge of materials will be kept well above potential puddles of rainwater;
• A secure, temporary covering that prevents direct water flow but ensures ventilation and combats condensation buildup on the glass should be provided;
• Protected areas of glass cases and preglazed materials should be marked clearly using colored ribbons or tape;
• Ensure that stored materials are not subjected to corrosive agents, such as concrete and masonry runoff;
• Ensure that stored materials are not exposed to activities of other trades such as welding, painting, insulating and fireproofing; and
• Establish a program for daily inspection of stored glass and glazing systems to monitor conditions and ensure prompt corrective action when needed.
As fenestration materials are delivered to a residential or commercial construction site, it is recommended that all construction trades be made aware of the potential for permanent damage and their level of responsibility in the event materials are subjected to harmful conditions. Site supervision must ensure that, in the event of damage, prompt attention is called to the conditions and a trained professional properly cleans the fenestration materials.
Site Handling and Installation
Trade professionals should execute site material handling and installation of fenestration materials. Residential and light commercial windows, doors and skylights should be installed in accordance with ASTM International document E 2112-01 – Standard Practice for Installation of Exterior Windows, Doors and Skylights. Glass for commercial glazing applications should be handled and installed in accordance with guidelines set forth in the GANA Glazing Manual.
Post Installation Inspection and Protection
After installation, special attention should be given to construction activities in order to prevent exposure of glass in windows, doors and skylights to welding, paint, plaster, sealants, fireproofing and alkali and chemical attack. The subcontractor and general contractor or builder should inspect and document the condition of the glazed materials on a daily basis. At this stage of construction, the general contractor or builder is encouraged to remind other construction trades of the potential for damage to the glazed materials and to implement systems for protection. The following is a list of common conditions and causes that damage glass after installation:
Condition: Wet glass, resulting in permanent surface corrosion/staining.
Cause: Outside, uncovered or extended storage; inadequate ventilation; improper glass separation;
Condition: Glass surface or edge damage.
Cause: Inadequate on-site protection; storage locations; exposure to other trades; Condition: Chemical attack and surface corrosion.
Cause: Overspray and runoff of chemicals from sealing/cleaning of concrete, masonry, roofing, etc; inadequate protection and/or poor storage location;
Condition: Weld-splatter surface damage and reduction in strength.
Cause: Location of glass near welding; inadequate protection of stored or installed glass;
Condition: Surface corrosion and stain from concrete and masonry runoff.
Cause: Poor storage and/or protection of uninstalled glass; absence of prompt, interim cleaning of installed glass during construction.
If glass is exposed to harmful materials or conditions during construction, the general contractor or builder and all trades should be advised of the potential damage immediately. The glazing contractor and glass fabricator/supplier should be consulted for damage assessment and corrective actions.
Deep surface scratches, contact by hot weld-splatter and edge damage threaten the structural integrity of glass and may require glass replacement. Surface contact with harmful materials will require prompt cleaning by a trained professional window cleaner. Glass should be cleaned in strict accordance with the Glass Informational Bulletin Proper Procedures for Cleaning Architectural Glass Products. General contractors, builders, owners and window cleaners should also consult the Glass Informational Bulletin, Heat-Treated Glass Surfaces are Different, for additional considerations when cleaning heat-strengthened and tempered glass products.
If harmful exposure results in conditions that cannot be cleaned using the industry guidelines, the glass fabricator/supplier should be consulted for recommendations on more aggressive glass polishing and chemical cleaning procedures. The use of a more aggressive procedure may itself damage the glass. Careful thought and discussion must precede the use of aggressive cleaning procedures.
The general contractor or builder may need to schedule regular cleaning during the construction process. Extended construction schedules and site conditions often result in dirt and debris build-up. Professional cleaning at the initial signs of build-up can decrease the potential for glass damage.
Long-Term Building Maintenance and Performance
Following the completion of the construction project and throughout the life of the building, windows, doors and skylights should be cleaned properly. Building facades may be exposed to sealant rundown, pollutants, dirt and debris, which can attack and damage glass surfaces over time. Building maintenance schedules should include frequent cleaning to ensure long-term glass aesthetics and performance.
Building owners should ensure that individuals who are cleaning fenestration materials are well aware of the products in the building and are knowledgeable of cleaning procedures and practices recommended by the manufacturer and the glass industry.
Proper protection of glass in windows, doors and skylights throughout the construction process and the life of a building is essential. Planning and execution of the practices offered in this bulletin will enable the glass to meet the aesthetic and performance expectations and the needs of the building occupants.
GANA Publishes GIB for Laminated Glass
GANA has announced the publication of its Glass Information Bulletin (GIB) titled Design Considerations for Laminated Architectural Glass.
“Today’s market demands for safety, security and protective glazing applications are dramatically increasing the use of laminated glazing materials and as a result, owners, architects and contractors need to be aware of design considerations when specifying these products,” said Greg Carney, GANA technical director. “The new GIB provides the design professional a list of items that must be considered as they determine aesthetic requirements for their individual project needs.”
The bulletin addresses the following:
• Aesthetic color;
• Optical distortion;
• Multi-ply laminates;
• Iridescence; and
• Product awareness.
This is GANA’s first GIB that addresses design considerations when using laminated glass products.
Tempering Division Forms Marketing Committee
GANA’s tempering division has formed a marketing committee that will work toward increasing division membership, promoting the use of tempered glass and providing educational resources to both the association and the industry.
Tempering division chairperson Ren Bartoe appointed Kris Vockler to serve as the committee chair.
Vockler is the global marketing director for Industrial Control Development (ICD) Inc. and a product specialist for OPACI-COAT-300 Aqua-Vue coatings. She has a bachelor’s degree from Portland State University and is currently working on her master’s degree from Maryhurst University.
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