Restoring The Building Envelope

Reglazing could be a viable alternative to total façade renovation.

By Michael Smalley
From the April 2023 Issue

A well-maintained building enclosure system is crucial for protecting a building’s structural integrity and ensuring the health and safety of its tenants and occupants.

A regular maintenance schedule can help building owners identify and address potential problems before they become major issues. This includes inspections of the roof, walls, windows, and other components of the building envelope to check for signs of wear and tear, damage, or deterioration. Many building enclosure companies will perform these evaluations at a low cost and provide valuable foresight about when a significant repair or restoration might become necessary.

In addition to maintaining the overall condition of the building, regular maintenance can help improve air quality and energy efficiency while reducing utility bills and operating costs. By implementing a periodic maintenance program and addressing potential issues early, building owners can protect their investment, maintain the value of their property, and ensure the health and safety of their tenants.

building enclosure
Building envelopes are sophisticated systems that require specialized knowledge and expertise to repair correctly. (Photo: IWR North America)

Finding Flaws In The System And Enlisting Help

There are different signs that can indicate a flaw in the performance of a building enclosure.

Among most common visual indicators is caulk pulling away from material or becoming faded. Condensation or effervescence can be seen through the façade, sometimes without an apparent source. If the inside of the building feels drafty, that’s a telltale sign of air penetration. Water could accompany air leaks around the windows and transition points. In extreme cases, this can lead to mold growth which then becomes a major health and safety concern.

Building envelope systems are comprised of many parts and pieces that individually are unlikely to fail. For that reason, it’s not uncommon to see material warranties lasting 20 or more years. But when different products conjoin to make one system, the transition of materials within the façade becomes the biggest question mark because it can conceivably be replicated 10,000 times throughout the system.

This is why DIY repairs are never a good idea. Building envelopes are sophisticated systems that require specialized knowledge and expertise to repair correctly. There’s potential to cause more harm than good by improperly trying to mitigate an issue without a full understanding of how the existing systems are working and interacting with each other.

Determining if the issue is isolated or systemic is a job best left to the experts. It takes a trained eye to determine the root cause of any problem and identify potential weak points over time. These experts have the necessary training to declare with certainty if the building envelope is functioning properly and make informed recommendations about how to best repair or restore the structure.

Reglazing As A Repair Solution

Reglazing is a technique that can be a viable alternative to a total façade renovation. It involves partially or completely reusing an existing curtain wall system to enhance the performance of the entire building enclosure.

building enclosure
The Royal Central Tower of North Central Expressway in Dallas. (Photo: IWR North America)

This retrofit solution is made up of two primary components: the system that holds the glass, and the glass itself. Even for identical buildings, every reglazing project will pose different challenges related to access, logistical requirements, and occupancy.

Among the most important parts of this process is determining the structural capacity of the existing system and whether it’s compatible to be used as part of a reglaze. If the structural capacity is lacking, the system may have to be completely replaced, which is very expensive and uneconomical. In that scenario, the better option may be starting fresh and considering a total façade renovation. Total renovations are often prompted by a change in ownership or use of the building and a concurrent renovation of the interior space. But for the purposes of reglazing, the system may only need to be reinforced, which is possible by installing support apparatuses.

The labor requirements for these reglazing projects are very intricate. It takes someone who has good working knowledge of existing systems. Like any selective demolition of a remodel, it takes a skilled and delicate hand to undo only the materials that need to be removed and maintain the integrity of what needs to stay. It also takes a great design team on the front end because it requires the application of engineering to an existing façade. One cannot simply rely on assumptions and risk compromising these systems.

Finding the optimal design solution can be a challenging endeavor that requires complicated calculations. Adding another layer of complexity, designers may have to understand a building system that was installed decades ago and become educated on its specific characteristics and limitations, while also understanding the new support system and how those elements interact and work together.

Façades erected in the 1970s and 1980s differ from their 1990s counterparts, which were generally built with different performing structural systems. Because of that, they may not be good candidates for a reglaze.

Reaping The Benefits

Reglazing is beneficial in many ways and yields immediate cost savings from improved energy efficiency and utility usage. It elevates and beautifies the building’s aesthetics and gives a new look to the existing chassis. In many cases, reglazing can be accomplished while maintaining full occupancy of the building and imposing minimal disruption to the interior space.

One such project that IWR is especially proud of is the Royal Central Tower of North Central Expressway in Dallas. It was executed in such a coordinated way that occupancy was maintained throughout the duration of the project. By replacing the entire south-facing façade with high-performance glass and insulation, the owner has experienced significant optimization in their systems. People did not take notice of the building before, but they do now.

Another notable benefit unique to the Royal Central Tower reglazing project was that it resulted in additional leasable floor space around the entire perimeter of the building, which amounted to hundreds of square feet over multiple floors that can potentially figure into rent arrangements. An overall feasibility evaluation will help determine if it’s possible for a reglaze project to gain leasable square footage.

Budgeting For Building Enclosure Upgrades 

Facility managers have to carefully prioritize which repairs to focus on first. Read more…

In addition to annual maintenance checks, building owners should also consider having their building commissioned every five years. It provides valuable data points that show if and where the building is getting outdated. This process is much more in-depth than visual observation and involves scrubbing, testing, and inspecting using innovative survey technology tools that scan walls and identify leaks or inadequately insulated areas.

Building owners who properly maintain their enclosures are sure to enjoy a less uncertain future when it comes to the integrity of these important assets.

IWR North AmericaSmalley is the Director of Preconstruction at IWR North America, one of the longest-standing contractors in the nation, specializing in building enclosures since 1895. Through a strong focus on building façades, IWR has become an industry leader in high-performing glazing, cladding and screening systems.

Do you have a comment? Share your thoughts in the Comments section below, or send an e-mail to the Editor at jen@groupc.com.

Click here for more news items and stories about the Building Envelope & Exteriors and Facility Management.