When a commercial renovation is in the planning stages, it is easy to want to get started as soon as possible. However, there are some important steps to take before anything else. A common step that is skipped is one of the most important—building inspection.Inspections comply with the scope of what is specified in ASTM E2018, “Standard Guide for Property Condition Assessments: Baseline Property Condition Assessment Process”. They involve, among other things, a comprehensive in-person inspection of the building’s construction, such as its structure and foundation, building envelope and more. Although completing an inspection can add cost and time, it can save more later.
“Inspections can be pretty helpful and, in most municipalities and jurisdictions, it’s the law,” explains Jonathan Barnes, principal of Jonathan Barnes Architecture & Design, Columbus, Ohio.
Owners and installers may want to forgo the building evaluation in favor of a “one size fits all” approach. This may work for a small residence, but hiring a professional on larger jobs can be well worth it. Potential benefits include environmental cost savings, properly specifying and esti- mating products, more accurate scheduling, and avoiding unpleasant and expensive surprises. Any one of these benefits could far outweigh the investment for the building analysis.
One size does not fit all. This is especially true when it comes to fenestration products.
Site- and Product-location-specific Evaluations
When specifying windows, doors, curtainwalls, storefronts or skylights for retrofit projects, a simple yet detailed process ensures the best products for the application are installed. This starts with an upfront investment in a site-specific building evaluation.
According to John Runkle, vice president of building science solutions for London-based inspection and certification company Intertek, the building enclosure has been largely ignored in retrofit projects, specifically ones that dealt with energy upgrades. Conventional wisdom was that the rate of return on investment for building enclosure upgrades was well in excess of 10 years. Now, the ROI is less than 10 years and sometimes less than five. This opens new opportunities for owners to save money, especially with renovation.
According to the “AAMA 2017/2018 Study of the U.S. Market for Windows, Doors and Skylights”, 155 million square feet of vision area was renovated in 2017. That number is expected to increase 5 percent by 2020.
A design professional can determine the correct specification for each fenestration product on the building. The evaluations and calculations are complicated and should only be performed by a licensed architect or engineer. Chapter 16 of the International Building Code (IBC) along with ASCE/SEI 7, “Minimum Design Loads and Associated Criteria for Buildings and Other Structures”, provides the details for determining the design loads for all exterior cladding, including fenestration.
This evaluation likely will determine the fenestration product’s structural design requirements differ depending on their position on the building and the project’s location. For example, the structural ratings needed to satisfy the code criteria on the front of a first floor of a large building facing an open field may be different than those required on the corner of a fifth floor at the back of that same building. Installing products per the worst-case condition could lead to over-specifying, causing undue costs. Under-specifying the product for the building risks future building issues and possible litigation.
Additionally, if the building was rotated 90 degrees on that same lot or if the building was set in an urban environment surrounded by tall buildings, each product’s required rating could change dramatically. Evaluations must be specific to the site and specific to the product location on the building. One size truly does not fit all.
How to Develop Specifications
Armed with this information, the design professional can develop the specifications for each fenestration product on the building. The Schaumburg, Ill.-based American Architectural Manufacturers Association (AAMA), along with the Washington, D.C.- based Window and Door Manufacturers Association (WDMA) and the Mississauga, Ontario-based Canadian Standards Association (CSA), recommends the AAMA/ WDMA/CSA 101/I.S. 2/A440, “North American Fenestration Standard/Specification for Windows, Doors, and Skylights (NAFS)”. The NAFS document serves as the IBC’s basis for product certification.