by Steve Marino
Premium unitized curtain wall and custom-built façades are par for the course in today’s highly creative building designs. Framed by tightening schedules and smaller budgets, successful commercial building projects need all stakeholders pulling on the same rope.
With the increasing complexity of façades, glazing contractors are relying heavily on accurate glass specifications to carry out their jobs. From project conception to completion, specifications provide a necessary “check and balance” to ensure that the proper products are being used and that current industry standards are being followed.
Although glazing contractors need to follow industry best practices, such as proper procedures for glass setting and using the proper glazing sealants, when installing the fabricated product, it’s equally important for them to review the glass specifications in their entirety to identify any “red flags,” errors, deviations from industry standards, special requirements or specific architect requests.
That’s not to say the entire responsibility falls on the glazing contractor. Because not all specifications are created equal, every party in the supply chain that receives the specification for a particular project—architect/specifier, general contractor, fabricator, raw materials suppliers—is accountable for ensuring that the product it manufactures complies with current standards.
An enormous amount of detail makes up a specification. It can address edicts ranging from general industry-accepted practices to precise performance criteria, such as glass characteristics, thermal and optical properties, and surface orientation for low-e coatings in an insulating glass unit (IGU). Yet, with building designs becoming more intricate and complex, it’s increasingly likely that an architect or specifier will add a spec to a construction document that deviates from industry standards.
So, how can glazing contractors best ensure that nothing falls through the cracks, and that the installation of the fabricated IGUs will comply with the specification and meet all stakeholder expectations?
With hundreds of potential variables in any single glass specification, it’s understandable that a detail might get overlooked at any point in the process. The impact of such an oversight, though, can range from a developer who is dissatisfied with the appearance of the constructed building to the replacement of all the glass on a project because a performance specification was missed. So, regardless of the fallout, there is a “price to pay” for an inaccurate spec.
It’s not a stretch to say that a successful project—one that is completed on time and on budget, and that meets the expectations of the architect, building owner and all other stakeholders—hinges to a large extent on accurate specifications that comply with current industry standards. Being aware of and staying on top of potential issues serves the whole supply chain well. At each stage, it’s a good idea to conduct a “self-check” by reviewing the following questions:
Identifying issues in a specification doesn’t require a “needle in a haystack” approach. Checking for these common errors first can often quickly reveal inaccuracies:
Other areas to check include:
Once issues are identified, it’s critical that glazing contractors inform their subcontractors.
So, the specification for a project arrives, and all seems to be in order, a fairly standard job.
Perhaps the project isn’t so “standard.” If glazing contractors focus only on, for instance, the performance criteria for the glass makeup or received just a few select pages of the specification—not the entire Master Spec document—key information could be missed, resulting in a building that falls short of expectations.
The architect has developed a very detailed spec that calls for heat-treated glass to meet the strength criteria for the building. To avoid a distorted, wavy look, the architect designates a “critical performance spec” for flatness. However, this information ends up in a section of the specification that other parts of the supply chain don’t typically review. The resulting glass product does not meet the architect’s requirements and he or she starts looking for a supplier to blame.
Although the work glazing contractors perform is based only on what the general contractor or architect provides, conducting a little “detective work” can go a long way. Check the entire specification, if feasible, for deviations or critical performance requirements that may be in a different part of the specification.
In addition, communication with upstream and downstream partners is vital. Because they are often more familiar with the overall scope of a project, general contractors can provide valuable insight into the visibility of, or expectations for, the project. For example, the glass specification for a new building being constructed in a major city and surrounded by iconic structures will likely have unique characteristics – perhaps the ASTM specification for a ¼-inch coating void is changing to ⅛-inch because the glass is in a high-traffic area of the building. Knowing the project’s prominence, the general contractor can “tip off” the glazing contractor of a potential deviation in the specs, such as a requirement that is tighter than normal ASTM specifications.
Several major trade organizations have developed publications or provide guidance that glazing contractors can reference to ensure that they are following the most-recent industry best practices. These organizations include:
A complement to these industry resources is Vitro's Construct an IGU tool, which allows glazing contractors to search, build and compare virtual glazing configurations, generate CSI-format specifications and evaluate performance characteristics for Vitro glass products.
For projects requiring additional support, Vitro also offers a robust suite of digital resources, including performance calculators, technical data sheets and BIM objects.
Architects and glazing professionals can also access Vitro's Project & Case Study Gallery to see how glass products perform in real-world applications, request samples for hands-on evaluation and connect directly with architectural and technical representatives for project-specific guidance.
Together, these resources help simplify specification development, improve decision-making and reduce the risk of costly errors by ensuring project teams have access to accurate, up-to-date performance data and technical expertise throughout the design and construction process.
One of the keys to a successful building project – one that achieves the look architects envisioned when they designed and spec’d the job – involves the development of and adherence to accurate specifications.
Architects set the tone for building projects, but every other element in the supply chain, including the glazing contractor, fabricator and raw materials suppliers, is responsible not only for providing their selected component in compliance with the final glass specification but also ensuring that those specs are accurate and thorough and reflect the most current industry standards.
Numerous resources, such as GANA/NGA, IGMA and AAMA, supply industry best practices, recommendations and specifications that are readily available to help in the glass-specification process. Each of these organizations comprises experienced professionals, who serve as “voices of the industry” to develop the recommendations and best practices for the architectural glass trade.
To learn more about the glass-specification process and helpful resources for writing clear, up-to-date specs, visit vitroglazings.com or call the Vitro Architectural Services Team at 1-855-VTRO-GLS (887-6457).