When to Repair vs. Replace: A Guide to Curtain Wall Remediation

Your building's curtain wall facade is its first line of defense against the elements and its most visible asset. Over time, factors like weather cycling, material fatigue, and installation defects can lead to performance issues, most notably water intrusion and air leakage. Deciding whether to undertake a targeted curtain wall repair or a full facade remediation is a critical decision that impacts budget, tenant comfort, and asset value.

Stage 1: Diagnosing the Problem

Before committing to a plan, a thorough building envelope inspection is essential. The goal is to identify the root cause of the failure, not just the symptom (like a leak).

Visual Inspection: Look for visible signs of distress, such as cracked or corroded aluminum framing, buckled metal panels, and especially deteriorated sealant joints and gaskets.
Water Testing: Targeted water spray tests (following standards like ASTM E1105) can confirm the precise location of the leak paths, often pointing to specific window seal failures or flashing issues.
Thermographic Survey: Infrared cameras can detect hidden air and water leaks by identifying temperature anomalies, which helps diagnose issues like missing insulation or thermal bridging.
Material Degradation: Analyze the condition of the glazing seals. If the perimeter wet seals or the internal setting blocks have hardened, cracked, or pulled away, the system is compromised.

Stage 2: Repair vs. Replace Criteria

✅ Choose Repair When: (Targeted Remediation)

Repair is the cost-effective choice for localized issues in an otherwise sound facade.

Localized Sealant Failure: If only a small percentage (e.g., less than 15-20%) of the exterior glazing seals are compromised. A simple sealant replacement program can resolve this.
Failed Insulating Glass Units (IGUs): When the air space seal on the IGU fails (causing condensation between the glass panes), the solution is replacing only the glass unit itself—a process known as re-glazing. The frame and gaskets remain intact.
Minor Hardware Issues: Simple fixes like replacing worn or broken operable window hardware, such as hinges, handles, or window actuators.
Targeted Water Intrusion: A clearly defined leak caused by a faulty pressure plate cover or a small gap in the air barrier system at a specific location.

🛑 Choose Replacement When: (Full Facade Replacement)

Replacement is necessary when problems are systemic, structural, or the result of outdated design.

Systemic Water Intrusion: If water testing reveals leaks across a majority of the facade, indicating a fundamental design flaw or widespread gasket and seal failure.
Structural Frame Degradation: If the aluminum mullions or transoms are heavily corroded, bent, or if the original structural glazing adheres are nearing the end of their design life.
Poor Thermal Performance: If the existing facade uses single-pane glass or non-thermally broken frames, replacement is often the only way to meet modern energy-efficient building standards and achieve a reasonable return on investment (ROI).
End-of-Life Systems: Facades that are 30+ years old are often past their facade life cycle and struggle to meet current wind load, seismic, or energy codes.

Final Consideration: Long-Term Value

While repair offers immediate savings, a comprehensive curtain wall replacement provides long-term value:

Modern Performance: New systems integrate modern technologies like low-E coatings, high-performance glazing, and advanced thermal break technology.
Reduced Maintenance: A new facade resets the maintenance clock, drastically reducing future repair costs for decades.
Asset Value: A new, high-performance facade significantly enhances the building's aesthetic appeal, tenant comfort, and overall market value.