Contributed by Roy Schauffele
The air barrier technology used in today’s construction and mandated by the International Energy Conservation Code (IECC) are firmly grounded in science. That database of knowledge continues to grow at an astounding rate. Research efforts by the Air Barrier Association of America (ABAA) will be presented at the ABAA Conference in 2019, and you will be astounded by how much research and testing that ABAA has been conducting to ensure better knowledge for all.
Currently, air barrier systems are being marketed with having passed only the air barrier part of the testing (ASTM E2357 - Standard Test Method for Determining Air Leakage of Air Barrier Assemblies) and pay little to no attention to the other architectural performance attributes, such as crack bridging, water resistance, adhesion to a substrate and fastener sealability, which when successfully passed, results in an ABAA Evaluated Assembly.
So, what I’m asking you to consider is an upgrade of performance requirements for a better and stronger air barrier specification. Here are my suggestions for ensuring the best possible air barrier performance for your project:
Performance requirements for a proper air barrier specification are vital. The above are four of my suggestions as how you can elevate and upgrade your specs. Should you have any questions or comments, I appreciate you commenting below. Thank you for reading.
Contributed by Elias Saltz
Getting this out of the way first, lest anyone accuse this article of being in the denial camp: Anthropogenic global warming is almost certainly real and will very likely have significant long-term societal, economic, and ecological consequences. Studying the processes that contribute to AGW, predicting the effects with a high degree of certainty, and finding technological solutions to reduce climate change’s impact should be a high priority of the world’s governments at all levels, as should incentivizing reducing carbon output from all industrial and business sectors.
However, some industries are more ready than others to make impactful changes, by dint of embedded scientific expertise and economic feasibility. The energy sector has low- (and zero) carbon options, for example, and the transportation industry is developing feasible technologies for reducing emissions as well. The building sector, for all of architects’ good intentions, is still a significant contributor of carbon emissions and architects, by dint of their lack of rigorous scientific and technical training, do not have the necessary expertise to contribute meaningful innovation.
In his recent column in Architect magazine, AIA President Carl Elefante writes that the newest design imperative is reducing and eventually eliminating carbon output from buildings. “A zero net carbon building sector is the architectural design imperative of our time,” he argues. In his article, he makes a number of problematic arguments.
First, Elefante invokes the changes made to make buildings more fire- and earthquake-resistant: “In 1871, the need for fire-safe buildings rose from the ashes of the Great Chicago Fire. In 1906, from the rubble of San Francisco came understanding that earthquake risk is a design imperative.” Elefante acknowledges that fires and earthquakes are singular catastrophic events that cause immediate death and destruction; specific deadly events shocked the public into demanding safety reforms that were rapidly baked into building codes. This is still a false equivalency. Climate change is acknowledged by the code writers and the International Energy Conservation Code, and requires incrementally improved energy efficiency in envelope design, mechanical and lighting systems. But since neither architects nor anyone else really knows how to make a building fully zero-carbon, let alone do it for a reasonable cost, there’s no true mandate for architects to follow.
Contributed by Roy Schauffele
I just reviewed another project from a different architect with the same recurring design misunderstanding. This is isolated to the parapet area of a building. I see this detail dozens of times a year and yes, I’m being Texan polite by calling it a misunderstanding.
The building is an administrative office for a Fortune 100 company. It is of steel stud construction with R-13 batt insulation between the studs, 5/8” exterior gypsum sheathing, an ABAA (Air Barrier Association of America) approved liquid applied air barrier (from Company XXX), 1” of an ABAA evaluated foil faced polyisocyanurate insulation (from Company XXX) and a metal façade. This assembly has an effective R-value of >13, which exceeds code. It is also an ABAA evaluated assembly and completely compliant with the Code Mandated Fire Requirement to NFPA-285, and since the air barrier and insulation were from the same corporation, chemical compatibility issues are avoided.
All is well on the front of the building.
Unfortunately, all is not well on the backside of the parapet.
The detailing of the parapet backside showed steel studs, R-13 batts and 5/8” exterior gypsum sheathing for an effective R-value of about 6.6, at best. Undoubtedly, this area is going to be highly energy inefficient and it will have a different dew point (the temperature to which air must be cooled to become saturated with water vapor) than the front of the building. When the dew point occurs, the condensate will drop straight in to the conditioned space, possibly causing mold and definitely leading to reports of a “roof leak”.
The fix is easy.
Just put 1” of your specified continuous insulation over the top and backside of the parapet and now your entire building has the same thermal envelope, with the same dew point profile on both sides of the building.
The advent of code required effective R-value and the use of continuous insulation has led to certain misunderstandings, but as I said above, there is an easy fix and it is in the paragraph above.
Contributed by Eric D. Lussier
While hosting a Let’s Fix Construction workshop at the AIA Conference in New York City this past Friday, a theme struck me during a discussion after a team was presenting their real-world solutions to the question that was posed to them. By nature, this theme seems opposite of the AEC industry in general.
One of the many reasons why Cherise Lakeside and myself have been travelling and presenting over the last year is to help eliminate the phrase “we’ve always done it this way” in construction. The industry remains stuck in many ways and tends to not implement changes easily, nor quickly.
So, I find it nothing short of ironic that the theme that struck, the term “FAST” seems so prevalent, including one long term usage, one definition that is on the cusp and one that I’m declaring.
While not an official project delivery method on its own, the term fast-track construction seems so common in the industry nowadays, that one almost assumes the term refers to the overall pace of the construction schedule.
However, according to the CSI Project Delivery Practice Guide, ‘Fast-track (construction) is the process of overlapping activities to permit portions of construction to start prior to completion of the overall design. The project schedule may require that portions of the design and construction occur concurrently.’
It’s my belief that the presumed definition and the true definition of fast-track construction are now blurred. Overall project construction schedules and durations have been shortened for years now, even while lead times are longer than ever for certain material procurement and the workforce isn’t supporting these timelines.
Before a shovel can be put in the ground and create the new blurred definition of fast-track construction, demands are being put on designers more and more in 2018 by Owners to create what I’m going to call “Fast-track design”.
The first six (of eight) stages of the life cycle of a facility traditionally moves from project conception to project delivery to design (schematic design and design development) to construction documents to procurement to construction. While these phases could take anywhere from a few years to upwards of twenty years in the past, a new norm has compressed this timeline upwards of eighty percent in some cases. While discussing public school design with a specifier recently, they recollected how a new high school design used to be allotted eighteen to twenty-four months for design in the past and what has become all too common is the same design is now being drawn and bid in as little as six to nine months.
Contributed by Emily Conner
American’s spend more than 90% of their lives indoors. The majority of those daytime hours are set inside the office walls. Despite the rise of e-commerce and remote workers, most businesses still operate out of traditional, energy-hogging buildings.
Collectively, our country’s building stock accounts for almost half of our annual total energy usage, 3/4s of our electricity consumption, and pumps out more than 39% of CO2 emissions produced in the U.S. The World Economic Forum also reports that the Engineering & Construction (E&C) industry is the nation’s single largest consumer of raw materials like steel. The Environmental and Energy Study Institute (EESI) predicts that, conservatively, by 2025 energy use in the business sector will cost more than $430 billion – about the same as our annual Medicare spend.
Businesses have a major opportunity to reduce their environmental impact. Where do they begin? Easy. A better-built environment starts with a more sustainable building sector. We’ve collected some climate-friendly ways to make a positive contribution.
But first, some quick business.
Potential CO2 and Energy Savings
The lifespan of an average building is 50-100 years. During that time, they produce tons of CO2 emissions every day. With new construction breaking records every year, we have the ability to make huge gains regarding energy efficiency.
As ESSI points out, “If half of new commercial buildings were built to use 50% less energy, it would save over 6 million metric tons of CO2 annually for the life of the buildings—the equivalent of taking more than 1 million cars off the road every year.”
So, there it is. Problem solved, right? New builds for everyone and our climate is saved? We think taking a more realistic course is a better plan of action.
Building Better with Sustainable Solutions
Let’s face it, not every business can afford to erect an entirely new LEED-certified green building and still have money to operate out of it. But there are ways businesses and construction companies both large and small can help transform the built environment.
Though this list is by no means comprehensive, here are seven moves that can inch us toward a better-built building stock.
Let's Fix Construction is an avenue to offer creative solutions, separate myths from facts and erase misconceptions about the architecture, engineering and construction (AEC) industry.
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