Building owners, specialty contractors, construction managers, engineers, and others understand that the building envelope – the building enclosure – is arguably the biggest driver of energy efficiency.
While mechanical systems and lighting also play a big role, the building envelope brings these separate operational systems together and keeps the energy they produce within the walls of the commercial structure. Experts say a building envelope that performs to its potential saves owners sizable dollars on energy consumption costs and contributes to long-term sustainability and reliability.
“As part of the commercial building process, there needs to be testing involved to make sure that the different mechanical and electrical systems are operating as they should,” said Katie Stein, a project manager, licensed architect, LEED-accredited professional and certified building enclosure commissioning process provider with Sitton Energy Solutions. “For example, a commercial structure such as an office building or warehouse might have 17 different systems, each installed by a separate subcontractor. Our job is to be involved with the owner from the beginning of the planning and construction process, setting up the owner’s project requirements and expectations for how the windows, walls and roof will perform to ensure that the end product is what they need.”
Stein and colleagues review drawings and specs, working closely with the building owner, architect and construction manager. Then once the subcontractors begin coming on board, Sitton Energy Solutions reviews submittals and works with through specific details with subcontractors. “anything involved in a wall – the foundation, waterproofing, air barriers, roof, everything on the six sides of a building,” Stein said. “It’s all critical to the success of the enclosure and ultimately the long-term performance of the building.”
Potential air leakage, water leakage and vapor leakage are all issues that receive close scrutiny. “You’ve got to think about all the systems and how they all tie together,” she said.” Making sure the building is sealed up tight, Stein added, also involves separate commissioning of the individual mechanical systems to ensure they’re interacting with each other and with the building enclosure. ” One of the most important things ans owner and construction manager can do is to ensure that the 3D mockup of the building is tester under a variety of simulated conditions,” said Stein. “Making sure the waterproofing is sticking, checking how the trim dovetails with the brick (façade), testing the heck out of the windows for any potential problems and simulating every aspect of the envelope possible before building the actual structure. Owners are becoming more aware than ever of how much money it can save them to get things done right in the first place.”
Michael Smalley serves on the board of directors for the Building Enclosure Council St. Louis Chapter along with Stein. Smalley is the preconstruction manager for longstanding building enclosure contractor IWR North America.
“It’s all about collaboration,” said Smalley. “It’s important to understand what building products are being used on the building envelope and how those different products will interface. Coordination and testing for compatibility between products will ensure products and systems will perform as intended for the life cycle of the enclosure. We’re seeing a lot of support from material experts to help assist with these types of efforts.”
IWR North America recently completed a corporate technology center in Chesterfield that included the commissioning of the building envelope. “Building owners are increasingly adopting more of a holistic view of the building itself and how the performance and longevity of the building’s internal systems rely heavily on building enclosure performance. Collaboration between enclosure designers and the mechanical system designers is becoming more common.”
Understanding the building’s function and intended life cycle and choosing enclosure products and systems to facilitate that is essential, Smalley said. “Is this a developer-funded project that is seeking a quick payback on investment? Or is it an owner’s project wherein long-term energy savings and low maintenance is a goal? The building owner’s concepts and desires should be established pre-design phase and then enclosure systems and quality control processes created to achieve these goals.”
Answers to the above questions, said Smalley, will often drive material selection and optimization, enabling project partners to provide options and solutions to achieve a balance between design intent and project budget. Smalley cited SSM Health St. Joseph Hospital (Lake Saint Louis) as a recent example where project specs included ordering material manufactured in the Netherlands. “The original façade cladding design was at approximately 50 percent optimization in terms of raw materials utilization. “Through collaboration with the project team including architect the Lawrence Group and TJ Wies Contracting, we were able to manipulate the façade layout to achieve close to 90 percent optimization of the material,” Smalley said.
Dave Foppe is the building enclosure product specialist at Negwer Materials in St. Louis. Foppe sees a continual emergence of cutting-edge systems and delivery methods.
“Because of how the warranties are structured, the building enclosure environment is not as much product-specific as it is complete systems,” said Foppe. “In essence, there we’re seeing four main types of building enclosure system: membranes, fluid-applied membranes, pre-applied sheathing and exterior insulation systems. The system choice depends upon owners’ and contractors’ preferences, what they’re comfortable with and what their facility objectives are.”
Budget also plays a role in owners’ selection of a building enclosure system that is good, better or best. Foppe said Negwer Materials hosts monthly knowledge seminars to educate architects, contractors and owners on the latest enclosure systems available because the industry is moving at warp speed in terms of advances in materials and methods.
“It all comes down to how well we seal up the building from air, from bulk water, from a thermal standpoint and to allow vapor to move through that wall for drying capabilities if there’s ever a problem and we have to go back in,” he said. “Balancing that exterior wall so that it performs correctly is critical to overall building performance and longevity.”
Aimee Rowbottom is director of architecture/interiors and Anselmo Testa is a national design principal at Jacobs Engineering. The global firm designs and engineers building enclosures for a wide array of industry sectors. Rowbottom says successful building enclosure systems are the result of a collaboration of expertise between designer, fabricator, installer, builder and systems tester/commissioner. “At the end of the day, the notion of specifications for the coolest, biggest, baddest, latest façade are just that… specs,” said Rowbottom. “Rather than focusing merely on how iconic a building is, we’re also intently concentrating on how well and how efficiently it is designed and constructed. Owners want reliable systems, but it’s more than the enclosure itself. It’s all about how the various building elements intersect and interact, as well as the mechanical systems. The reality is about where design and function meet,” she added. “Building owners don’t want to incur the cost of a building system that has to work like a draft horse in order to keep up.”
Visualize the building enclosure systems as being stitched together, said Testa. “That’s usually where your weaknesses are. New amendments, energy code requirements and sustainability guidelines such as Green Globes or LEED are demanding better and better performance. We have to get beyond looking at the building enclosure as a separate system and truly view it as a cohesive unit,” Testa said, adding that all the other building systems depend upon the performance of the building enclosure’s ability to perform as it was designed and built to do.
“BIM (Building Information Modeling) and commissioning are helping us all accomplish this,” Testa said. “Whereas 30 years ago we crossed our fingers that it would work, now we have the opportunity to test it in advance. There’s software that allows us to start this at the concept design stage, as opposed to coming in later when the building has already been designed. At this early stage, we can already begin testing. How should we orient the building to provide maximum benefit with respect to solar energy? Should the building enclosure be glass or opaque? How can we take advantage of the natural environment of the site? How can we optimize prevailing winds to impact the size of cooling units? There’s so much more we can learn, design and test much earlier on in project planning to meet owner expectations and maximize value.”