The ticking time bomb of exploding tempered glass

Key takeaways from the NAREIM Architecture & Engineering meeting

Austin, September 28-30


Managers were advised to avoid using fully tempered glass wherever possible, to avoid the “ticking time bomb” of nickel-sulfide inclusions – a chemical imbalance that can cause sheets of glass to break, sometimes crashing in chunks onto sidewalks below.


NiS, as nickel-sulfide inclusions are called, are becoming an increasingly-recognized problem in fully tempered glass (FT), often appearing decades after a building was constructed.


“It’s a ticking time bomb in your glass,” the meeting was told – with no ability to detect it and almost no means to treat windows before breakage.


Instead, managers were urged to minimize the risk by using safety glass wherever possible, rather than FT glass, and where reinforced glass was required by code to look to alternatives such as laminated glass or heat-soak tested FT glass.


Moreover, the meeting heard, managers should have a response plan in place to deal with a potential issue if it arose, including keeping the glass fragments for analysis, documenting breakages exceptionally well, and ensuring staff in the building knew what they all needed to do in the case of spontaneous breakages.


  • To download the presentations from the Architecture & Engineering meeting, please click here.


The Architecture & Engineering meeting, which was NAREIM’s first in-person meeting of 2021, also discussed general contractor (GC) audits – and how 95% of billing errors made by GCs are intentional.


In a roundtable conversation, members heard expert tips on how to spot padding by GCs – and were told: “Anything you don’t get an invoice for is the most common area for over-charging.”


Two examples involved:

  • Labor rates: A large international construction company billing $41 per hour for a union, carpenter journeyman for a project, but paying just $12.25 per hour for a non-union laborer.

  • General liability and excess liability insurance. Typical insurance for GCs is, on average, 0.3%. However, managers will often be billed between 1% to 1.5%.

  • The same was true for catastrophic insurance, with the premiums, deductible and co-pays often making it unfeasible for GCs to buy coverage.

  • Advice: Ask for the proof of insurance and the invoice.


Other takeaways from the meeting included:

  • When dealing with GCs and critical path scheduling – the timeline that tracks the GC and subs’ progress on a project – make sure you have the native files and not summary views to ensure information is not being hidden from you.

  • While there are often thousands of task lines in a critical path schedule, in almost 50% of claimsowners were never given the original schedule file – and were instead provided summary PDFs only. Managers were recommended to specifically request a native file in their development contracts, versus just an electronic copy.

  • Timber-framed offices may have a 3-5% higher hard cost than traditional construction but the speed to market is significantly better – sometimes two-thirds faster than steel and concrete.


To download the presentations from the Architecture & Engineering meeting, please click here.


Meeting topics covered:

  • A&E Shark Tank: emerging technologies

  • Climate risk

  • Critical path scheduling

  • Contractor audits

  • DEI 

  • Net zero

  • Timber-framed construction

  • Spontaneous breakage in tempered glass

  • Check out the 2021 agenda here.