Guess it all depends on the criteria being used to define what “perfect” really means, but if there is one person on this planet of ours that might have a clue what the perfect wall is, it is Joseph Lstiburek. At the wonderfully named Let’s Fix Construction website, building scientist extraordinaire Lstiburek contributed an article with the bold title, The Perfect Wall.

In truth, the article goes well beyond the scope of describing what a “perfect” wall might be, and could instead be titled, The Perfect Building Envelope. Besides walls, Lstiburek also diagrams the components of the perfect roof, the perfect slab, as well as providing several variations on wall design options.

Getting back to the definition of what a perfect wall actually is, here is the introduction:

The perfect wall is an environmental separator—it has to keep the outside out and the inside in.  In order to do this the wall assembly has to control rain, air, vapor and heat. In the old days we had one material to do this: rocks. We would pile a bunch or rocks up and have the rocks do it all. But over time rocks lost their appeal. They were heavy and fell down a lot. Heavy means expensive and falling down is annoying. So construction evolved. Today walls need four principal control layers—especially if we don’t build out of rocks. They are presented in order of importance:

  • a rain control layer
  • an air control layer
  • a vapor control layer
  • a thermal control layer

A point to this importance thing here, if you can’t keep the rain out don’t waste your time on the air. If you can’t keep the air out don’t waste your time on the vapor.

You’ll definitely want to read and bookmark the full article. Just be prepared — this is some seriously geeky building science content. But what else would you expect from the founder of the Building Science Corporation?

Ronald Ray, writing for Construction Specifier, has a great article on different methods for detecting, diagnosing and pinpointing the location of leaks within various types of roofs. What makes Ray’s article so great is some of the cool new technologies outlined representing the bleeding edge of building forensics:

All roofs eventually leak—it is just a matter of when and where. Nevertheless, the hope is that new roofing systems do not leak right from the start. It is critical to verify the watertightness of roofing, especially if it is to be covered with ballast or a vegetated roof assembly. This verification is a field quality-control measure beyond the scope of a roofing manufacturer’s visual inspections for issuance of a warranty. For existing buildings being considered for a reroofing program, conducting a roof survey to determine the location and extent of wet substrates is essential to making fiscally responsible decisions related to the program’s extent…

Other technologies, such as electronic leak testing, can detect leaks with far more reliability than flood-testing. Some electronic leak-testing methods include:

  • electrical capacitance/impedance testing;
  • infrared thermography;
  • nuclear hydrogen detection;
  • low-voltage electrical conductance testing; and
  • high-voltage spark testing.

Building Information Modeling, or BIM, is a method of designing buildings using sophisticated 3D software that makes it much easier to visualize how various components and systems come together in a 3D space and how they will interact or interfere with one another. Perhaps most importantly, BIM facilitates identifying potential conflicts/defects prior to construction, and is a very powerful tool for sustainability by supporting the integrative design process.

Unfortunately, the construction industry isn’t exactly well-known for its rapid adoption of the latest technologies and the majority of A/E/C firms have yet to implement BIM as part of its workflow. Since few A/E/C professionals use BIM, even fewer are going to be able to articulate the benefits of using BIM to building owners.

For that reason, the National Institute of Building Sciences (NIBS) has developed the National BIM Guide for Owners. Here’s what they have to say about it:

A building information modeling (BIM) guide for building owners has been developed under the auspices of the National Institute of Building Sciences. The National BIM Guide for Owners is a new guide that building owners can adopt to provide a documented process and procedure for their design team to follow in order to produce a standard set of BIM documents during the design and construction of the facility, and for maintenance and operations of the facility upon handoff. The National BIM Guide for Owners is based on the foreign, federal, state and local BIM guides that currently exist, but geared to a generic facility with uniform requirements for use by a variety of government, institutional and commercial building owners. It references a range of documents and practices, including those contained within the National BIM Standard-United States® developed by one of the National Institute of Building Sciences’ own councils, the buildingSMART alliance®.

You can download the full guide in PDF format directly from NIBS.

Legionnaires’ Disease is a pneumonia-like affliction that affects a minority of people exposed to the Legionella pneumophila bacteria. It was first identified when 221 people attending a reunion for members of the American Legion that took place around the nation’s bicentennial in 1976 fell ill. Sadly, 34 of those people lost their lives and it wasn’t until January, 1977 when the cause of the mysterious illness was discovered.

After a recent outbreak in Hopkins, Minnesota which left one person dead and 23 sick, scientists were able to utilize DNA-sequencing to conclusively determine that the cause was a cooling tower at a manufacturing center. Those infected breathed in air in which Legionella had become aerosolized as a result of the cooling tower. What’s particularly frightening is that this cooling tower is less than 3 years old and exhibited no indication of defective construction. (more…)

Apparently, the Hartford, CT Mark Twain House & Museum contains an amazing collection of artifacts collected by Samuel Clemens throughout his life. Sadly, however, much of that collection has been threatened by mold growth caused by a faulty HVAC system.

According to Susan Dunne of the Hartford Courant:

In November 2015, mold was found in the storage facilities of the historic home’s museum center, tainting at least 5,000 of the museum’s 16,000 artifacts. The vulnerable pieces are varied: 19th-century furniture, upholstery, metal, glass and leather items, as well as books, including some Twain first editions and translations, whose fabric and leather bindings are conducive to mold growth. The spread of the mold has been halted for the time being — the HVAC system has been repaired and the archive’s relative humidity is being carefully monitored — but the task remains to remove the mold that already is there…

More specifically, the cause was related to a rather sophisticated geothermal heat pump system designed to use substantially less energy than more traditional HVAC systems.

“The motors in the geothermal wells that moderate the temperature in the building would break down regularly,” Lamarre said. “One of the wells malfunctioned, causing enormous pressure to build up in the system. The pipes in the mechanical room burst in multiple places, causing water to flood down the back hall of the museum center. The auditorium was flooded with a foot and a half of water.”

“The explosion of the geothermal well led to an increase in the humidity problem in the building at large because the decision was made to cap the wells instead of repairing them,” he said.

This isn’t the first time the historic home and museum has faced operational issues, however. From 2002 through 2010, a former employee of the organization embezzled more than $1-million. In 2008, the organization laid off 33 of its 50 employees following a financial restructuring.

Sanjoy Malik, writing for Green Biz, discusses an issue that is something most building owners, developers, operators and other stakeholders aren’t too familiar with. However, for those of us with experience in improving/optimizing existing buildings, the issue can be a real deal breaker.

What’s the problem? Since de-regulation of the energy utilities, the data produced by rate-payers is now proprietary. Without readily available access to both quantitative and qualitative data regarding the energy usage of existing buildings of certain sizes and use types, it is extremely difficult to develop new strategies for improving efficiency. (You can’t improve what you can’t measure…)

Malik proposes a new business model mirroring the Software-as-a-Service (SaaS) model that many technology providers have successfully exploited in the past decade or so:

The Energy-data-as-a-service (EDaaS) model holds great promise for the industry. There are various firms providing services within the energy industry that could benefit from a single source of energy data, including:

  • Accounting and finance. Many firms provide energy budgets, pay utility bills and forecast future costs and progress towards reduction goals. These activities require significant process-oriented operations and analysis capabilities. Adding the acquisition of energy data may be too much effort for these firms.
  • Energy optimization. Energy performance in many buildings can be improved using more detailed data, analyzing it and creating statistical models that include other variables such as weather and occupancy. Firms that provide such analytics products can scale their operations by using a standard energy data provider.
  • Energy procurement and supply. Energy purchasing decisions are complex and firms that provide these services typically invest in analysis of historic bills and bidding and negotiating capabilities to find and secure the best prices on energy. By using a third-party for the raw energy data, they can more quickly make decisions about the procurement strategy for their clients.
  • Sustainability and compliance. Many firms are investing in greater transparency around energy performance, using sustainability reports and other public information disclosures. Many large cities are starting to mandate that building owners get Energy Star scores to benchmark their properties. Both of these processes can be expedited by more quickly and systematically collecting energy data via a third party.

On December 8, 2016, an office building in Boulder housing two local high-tech firms had to be evacuated after the partial collapse of the second floor due to a beam whose structural integrity had been negatively impacted. Nearly 280 people were temporarily relocated until repairs could be made.

But before repairs can be made, someone has to figure out what went wrong, and how best to fix it. As is often the case with forensic building assessments, these things can take time.

Seven weeks after the collapse, building owners and tenants alike are still awaiting further information. The Daily Camera’s Jerd Smith says that the cause of the failure remains a mystery:

Dave Thacker, chief building officer for Boulder, said the city is waiting for a forensic engineering report to be completed before determining what if any citations might be issued and what corrective actions might need to be taken. In the meantime, it has issued permits to allow for initial inspections, creation of a “safe passage” for construction workers, the shoring of the building’s foundation and the floor’s repair…

Such structural failures in commercial buildings are “unusual,” Thacker said. Among the theories under discussion include a weakening of the building’s foundation, due to the 2013 floods or a below-ground water leak, but no one has ruled out other causes as well, he said.

According to a preliminary investigation of the site, a connection tying a massive steel beam to a metal plate embedded in a concrete column sheared off. The beam supported the second floor. What caused the beam connection to fail is unclear.