LEED BD+C: Core and Shell v2.0
The Christman Company Headquarters Fit-Out
LEED Platinum 2008
* This profile has been peer-reviewed by a USGBC-selected team of technical experts.
Goals and successes
What were the top overarching goals and objectives?
The top goals were to:
- Represent the company’s core values, people, energy, expertise, accomplishments and history.
- Encourage team collaboration internally, with branch offices and customers in both informal and formal settings.
- Create an environment that shares successes and energy and provides for mental and physical breaks.
- Maximize comfort with individual thermal and lighting controls, ergonomic workstations and daylighting.
- Plan adaptively for growth, change and the space needs of short-term, on-site project personnel.
We planned and renovated the building to achieve these primary goals rather than designing to get LEED credits. We used the LEED Checklist to gauge how we did, rather than "chasing points."
What were the motivations to pursue LEED certification and how did they influence the project?
At the time there was, and still is, a perception that LEED buildings have to cost more and also that it is difficult to combine historic preservation and sustainable, LEED certified, construction in a cost effective manner. Our experience was different and with this project we felt that we had a perfect test case to prove that using an integrated design and construction process, clear project goals and careful life cycle cost analysis you can build a historic preservation, high performance sustainable, Class A, headquarters office building at minimal additional cost.
Aside from LEED certification, what do you consider key project successes?
The project had to be completed in accordance with the very rigid standards for historic preservation projects as defined by the Secretary of Interior and the United States National Park Service. The goal for rehabilitating the historically registered structure into a "green" building suited for modern office use without jeopardizing millions of dollars in historic tax credits posed significant challenges to the team, but resulted in a big success.
One key success is that we redeveloped this historic building while maintaining much of its historic character.
A "new lease on life" doesn't even begin to describe the exciting things we’ve watched happen to this old building in an incredibly short time. It’s one thing to say you’re committed to downtown revitalization and urban renewal, to historic preservation and environmentally-friendly building practices. But when you see a company like Christman, a major downtown anchor for the last 80 years, put its money, skills and passion where its mouth is and come up with something this incredible right here in downtown Lansing, you know it will inspire other businesses to move or remain here in the rapidly rejuvenating core of our city.
What were the most notable strategies used to earn LEED credits?
All strategy decisions were made using a detailed life cycle cost analysis (LCCA). We installed efficient HVAC systems - including an underfloor air distribution system, multi-stage boilers, roof top unit with fully modulating burners and a chiller – at minimal additional cost, earning a number of Energy & Atmosphere and Indoor Environmental Quality credits. The underfloor air distribution system selection was based on some pretty in-depth LCCAs that we did early on in the process. We used this to determine which HVAC system to choose.
Individual temperature control.
We analyzed two basic systems – a standard overhead variable air volume (VAV) system and the underfloor air distribution system, based on lots of varieties (like rooftop units or hot water systems, etc) of each system. We analyzed not just the cost of the HVAC system, but also its impact on the other building components. We found, for example, that if we went with an overhead VAV, we would have had to drop the ceiling two feet, thereby covering up the top quarter of the windows. And in analyzing the cost and impacts of this duct work on the design, we determined that the underfloor air distribution was only tens of thousands of dollars more than the overhead VAV, but that it made up for this substantially in ongoing energy savings. It paid for itself, also resulting in the ability to maintain full window exposure (enabling daylighting and increased ventilation at minimal additional energy costs), and resolving numerous architectural issues related to beam placement. With the sub-systems, we used LCCA to decide on adjusting from the original design of six boilers to install two boilers with four stages of heating each, which gave the same capability of staging as modular boilers at half the cost. Additionally, reusing the building (MR credit 1) and historic lighting, door hardware and wood molding (MR credit 3) proved to be cost-effective and reduced the need for virgin materials.
Sustainability programs manager Gavin Gardi describing how The Christman team used LCCA to make decisions.
We used an underfloor air distribution system. We weren’t initially sure if this was the right fit for a historic building, but the combination of the floor plate and how the work stations would be arranged led us to an underfloor air system using a linear diffuser system raised at the window sill level of the work stations. This is fed from an underfloor system, but is in the wall. By arranging the system and setting back the workstation sills, this system was a real good fit for the floor plate.
Mechanical engineer George Karadis (smith group) describing Christman's underfloor air distribution system.
In planning the corporate offices, the designers took advantage of the large perimeter windows and were able to provide day lighting to 92% of occupied spaces and outside views to 90% of the occupants. This was key to increasing worker comfort and productivity. Through the use of high-efficiency indirect lighting optimally located by calculating luminance and illuminance levels, occupancy sensors in private offices, conference rooms, toilets and stairways – combined with programmed timers in common spaces, occupancy controls and individually controlled task lighting – the design for the lighting system is projected to result in approximately 27% energy savings over ASHRAE/IESNA Standard 90.1-2004. We used a lighting system that combined ambient lighting with task lighting for lower energy consumption and increased user control. The electric lighting was paired with a design strategy that sought to bring natural light farther into the space through the use of interior glazing and clerestories at perimeter spaces. This strategy not only facilitated shared light, but also allowed for views to the exterior from interior spaces of the deep floor plate.
A new sky-lit atrium, open to the fourth and fifth office floors as well as a new sixth-floor conference center, was created by enclosing what had been an open-ended light well located at the center of the U-shaped building. In addition to its use as an informal gathering and collaboration area, the new inner courtyard serves as a focal point and supports the organization’s goals toward unification and collaboration. It is also a key factor to ensuring that nearly all employees have access to natural daylight. The space has quickly become the favorite place to work due to the quality of daylighting and architectural character of the space.
What additional green strategies did not directly contribute to a LEED credit?
Sustainability is not incompatible with historic preservation; you can blend the two together, but it can require trade-offs. The biggest example of this was that while we wanted to maximize the energy efficiency of the building and envelope, because of mandates from the Secretary of Historic Preservation, we were obligated to keep the original windows. We could have replaced them with replicated windows, but this would have been cost-prohibitive. After evaluating everything in terms of return on investment and cost-effectiveness, we had only one option: To retain the original windows, restore them, and retrofit them with insulated window systems. So we kept the original sash and installed double-glazing within those (more residential in nature at one-half-inch thick compared to the traditional one-inch thick).
Architect Brooke Smith (Smith group) describing how The Christman team balanced sustainability with historic preservation
Full cut-off exterior lighting fixtures were installed to reduce energy use and light pollution. Due to the proximity of the building to the property lines, the related LEED credit was not achieved, although the intent of the credit was met.
What cutting-edge strategies or processes were implemented?
This was the first building to use a variable aperture linear VAV underfloor air system, a system that we developed with Titus called the Titus TAF-L, which also incorporated hydronic heating for the first time. This system accommodated the extensive perimeter zone exposure of the typical office floor plate, with built-in workstations abutting the exterior walls. The underfloor air distribution system was fed up to the window sill height from the floor plenum.
What considerations were integrated into the lease to support LEED certification?
Ten-year-long term leases were negotiated with each of the three major tenants.
What products were most effective in helping to meet project goals?
A variable volume version of the Titus TAF-L linear UFAD system, which also incorporated hydronic heating for the first time, was new to the market. This system accommodated the extensive perimeter zone exposure of the typical office floor plate, with built-in workstations abutting the exterior walls. The UFAD system was fed up to the sill height from the floor plenum.
How was the integrative process applied and what was the greatest benefit gained?
The team was committed to an integrated or holistic approach to design; it was very iterative and hands-on with all architecture and engineering (AE) participants, and the owner had a separate development arm coming from a unique perspective on the finance side, plus a construction arm. We had owner-architect-contractor meetings on a regular basis and every issue that came up during the design process was thoroughly vetted out. All stakeholders were at the table at every single meeting. We identified program, design, and performance issues, always with someone form each position representing their interest and asking the “what if” questions. From the AE side, we were thereby able to consider many different perspectives and alternatives. We made sound business decisions, including from things like the primary HVAC system to considering any extraordinary energy options we could have incorporated to selection of materials and finishes. We evaluated options on a lifecycle cost and ROI basis. If something made good business sense, it would garner additional consideration; if it made no financial sense, it was eliminated. We couldn’t have done this without the owner (in its full capacity as owner, financier, developer, and builder) being at the table every step of the way.
This project proved that sustainable design and construction need not cost more than conventional practices. Commitment to the LEED approach and collaboration among the owner, project team and subcontractors was essential to success. The team was really a powerful part of achieving good sustainable design, with Christman’s desire and commitment; Gavin Gardi’s persistence in looking at the systems and achieving results; and a common strong goal. Smith Group has a long tradition of architects and engineers and that’s the way we live and breathe. When the issue arose regarding how the workstations would work with the underfloor air distribution, the integrative approach was critical, including for applying the architectural adjustments of raising the walkable floor levels to accommodate the historical aspects of the building.
The team’s integrated approach was critical to getting a great design and great performance out of a historic building (and all the restrictions that come along with that). Ceiling heights, deep floor plates, and obstructions were just a few of the obstacles that the team had to navigate and coordinate closely for the project to come together and achieve the performance we were targeting. A great example was glazing selection for replacement windows, which had to be carefully studied to balance solar heat gain, visible light transmittance, and historic preservation approvals for appropriate appearance.
Which building codes, zoning or regulatory requirements influenced decisions and how?
This is the first building in the world to receive triple LEED Platinum Certification and it was accomplished while adhering to the Federal and State requirements for Historic Preservation Tax Credits.
All of the preservation work on the building was approved by the State Historic Preservation Office and the National Park Service to ensure that standards protecting the National Registered building were upheld. Restoration of historically significant building features includes the main entrance doors and plaques, the mica shade light fixtures and Pewabic wall tiles in the main hall, and the light fixtures and verdigris bronze handrail finish in the stairwell and lower level.
Bricks salvaged from the removal of the penthouse have been used to patch exterior walls. Benign products, such as citrus strippers, wet grinding, and low volatile organic compound (VOC) coatings were used to restore historic finishes, such as the walnut paneling in the executive offices on the first floor. All plaster walls were restored using several restoration techniques.
When was energy modeling used and how effective was it?
Energy modeling was employed during the design phase. After disappointing initial energy results, recommissioning addressed multiple issues (including simultaneous heating and cooling), which led to energy results better than the initial modeling predicted - an ENERGY STAR rating of 81 versus 75 as modeled, essentially retaining the historic exterior wall system.
What value did commissioning add?
To ensure that all components and the entire HVAC system were operating per the design, the commissioning identified both sensors and controls that were either out of calibration or not operating properly. That, along with the fine tuning of schedules and operational sequences, was reviewed to confirm the proper settings and uses. Commissioning also identified fire dampers that were not open, as well as simultaneous heating and cooling in the underfloor air distribution area that was resolved.
What synergies impacted the project and how?
The fundamental decision to use an underfloor air distribution system versus a traditional overhead system, in the end, gave us many LEED points. Aside from LEED points, we looked at this from a cost and lifecycle analysis perspective. There were so many synergistic benefits and issues resolved by making this decision, including: it’s a far more efficient system, initially and from an ongoing operating perspective; it’s higher-quality in terms of the environment; and it also solved other problems that contributed to our LEED strategy. For example, by introducing 12-inch-high access floor system, it reduced the dimensional differential between the bottoms of window sills and the floor such that we could garner daylighting and view LEED credits. We had accessibility issues throughout the building where there was a lot of up and down – by raising the floor, it eliminated 90% of those transitional problems. We had some structural issues, where we had to reinforce or repair areas or level floors, and again, this system enabled us to overcome that. The underfloor air distribution system was a bit of a silver bullet that helped us address so many challenges associated with this building, and at the end of the day, it improved the quality of the environment, it was incredibly cost-effective from an initial construction and operating perspective, and the owner’s cost analysis determined that it would be no more expensive than an overhead system.
This project is a great example of a public/private partnership. Financial incentives for historic preservation and brownfield redevelopment made the project financially feasible, whereas it would not have been without them. The City of Lansing, through the Brownfield Authority, has a development agreement with the project. This enables the recapture of Michigan Single Business Tax Credits for eligible costs associated with the project. The City also provided key economic information that supported requests for the New Market Tax Credits. The City of Lansing, knowing that a healthy downtown leads to healthy communities, was eager to assist in the development of the project. Preservation of this landmark building has made a substantial contribution to Lansing's downtown revitalization. Using this project as a test case, we were able to prove that there is a real synergy when historic preservation and sustainable construction are combined.
Another synergy was that reuse of the building structure, door hardware, lighting and molding tapped into the embedded energy, resources, and skills inherent in a historic building - reducing the need for virgin materials and the energy use and pollution needed to produce them.
The greatest synergy was the benefit of the historic building fitting with the underfloor air distribution. One aspect that led us to the underfloor air distribution decision was that there was enough height to the bottom of the window sills to accommodate the raised floor. There were also already-existing architectural features that enabled seamless accommodation of the floor, including a sloped roof slab and raised concrete beams at the edges under a middle roofed-over area that the team wanted to use as occupied floor in the center of an atrium feature.
What were the most important long- and short-term value-add strategies and what returns on investment (ROI) have been experienced or anticipated?
The cost for all sustainability initiatives added approximately 2.0% to the cost of the project, of which 70% of the added costs are attributed to the LEED certification process. In addition to the financial benefits of increased occupant comfort, health, and productivity, the owner expects to see a four-year return on their investment in green construction through the building’s increased energy efficiency. It’s important to note that this project could and would not have happened if we had not been able to secure historic tax credits and incentives. About 30% of financing came through non-traditional finance, and all of those financial resources were tied to time.
Energy modeling projections for this building show that it will exceed minimum energy efficiency requirements by 34% natural gas and electricity consumption savings will reduce CO2 by 1,002,945 pounds per year, SO2 emissions by 4,524 gm per year, and NOX emissions by 2,148 gm per year. This is the equivalent of planting 4,112 trees or reducing driving by 1,094,212 miles. The underfloor air distribution system provides 200% to 300% more ventilation to the breathing zone than required by ASHRAE Standard 62.1–2004. The computerized building management system (BMS), which has several thousand control points, is used extensively for fine tuning the operation of HVAC and lighting systems to occupancy and climatic conditions. A 40% reduction in potable water and sewage use was achieved by careful selection of water-efficient plumbing.
How is occupant behavior impacting the project’s sustainability?
Read more in The Christman Building LEED for Existing Buildings: Operations & Maintenance profile
Beyond the project, what impacts have the LEED and green strategies had?
The Christman Building project has received more coverage and interest in the marketplace than virtually any other project we’ve ever been associated with. How you measure that in terms of dollars and cents and contribution to our obtaining work, I can’t answer. But beyond coverage directed at Smith Group, Christman receives countless inquiries; they’re constantly being asked by groups across the globe for tours of the project. And we’re pleased not just from the standpoint that this is good exposure for Smith Group, but also for the green building movement.
Although being the first to achieve triple LEED Platinum is unquestionably a rewarding thrill for our company, it is in reality merely a by-product of our quest to provide the best possible tools and expertise to our customers in achieving their own green building and operations goals. What better way to learn how to do that than by taking ourselves through the process, and experiencing it first-hand from an owner’s perspective?
What project challenges became important lessons learned?
The biggest lesson learned deals with the significance and role of commissioning to reach energy goals. We worked with Christman’s contracting and development group to design an appropriate solution in the way of energy benefits. The initial commissioning was done through an in-house party after occupancy due to time constraints. This meant that we designed a system or series of systems that weren’t performing nearly to what we intended, and the owner saw high utility bills. Through this revelation, Christman developed a recommissioning team including the Smith Group and we all recommissioned the building, in collaboration with the original contractor, and got it to the point where it was fine-tuned and running like a well-oiled machine. In addition to having an appropriate commissioning process, it’s important that the person who handles the commissioning has the right knowledge, experience and credentials.
It was also a huge challenge to fulfill many contrasting, often contradictory, project objectives. We wanted to prove to the marketplace at large that you can create a sustainable headquarters building without making sacrifice of aesthetics. This project has many facets to it and is greater than the sum of its parts: it’s a historic preservation project with its own unique challenges; creative financing tied to an aggressive schedule was used to support it; the owner wanted a very traditional, corporate headquarters aesthetic that drove the project in other directions; it’s a building comprised of largely conventional systems in the sense that it doesn’t have many extraordinary systems, such as photovoltaics, wind, and solar; and it needed to be LEED. When you weave together all of these drivers or goals, it was a challenge to balancing these conflicting objectives. Compromises were made – for example, there is quite a bit of wood flooring, but it’s not sustainable wood because the owner didn’t like the sustainable options, so we had to give up a LEED point to fulfill another objective. We overcame these challenges by taking an integrative approach.
The biggest challenge was that there were artificial timelines established to get two million dollars' worth of tax credits, so the project had only a seven-month construction period. Thrown into this were delays resulting from the Department of the Interior’s historical preservation approval process. The last phase – controls work and commissioning – were scrunched into a period of just a couple of weeks when it should have taken two months. Also, the controls technician was changed one week into this two-week process, so a lot of things didn’t get done that normally would. The result was that the work didn’t get done properly and performance was lower than designed. Until recently, we did commissioning as cheaply as possible. We had one of our people do the commissioning; he’d gotten his certification after a week-long course. He did a fairly good job of commissioning and functional checking of individual systems (such as air handling units and the chiller), but didn’t do as well commissioning the individual systems working together as a whole. We did it in-house; we’re not a commissioning company. It’s not something you want to short-change.
My advice to other project teams, based on this project:
- Be aware of the risks and consequences of meeting artificial time frames. Understand that there’s a certain time required to implement a high-performance, complicated HVAC system – if you don’t, you’ll need to do it correctly later.
- Verify, during the selection process, that the individual controls technician assigned to the project has the required skills and experience to complete the installation and that sufficient time is allocated in the contract.
- Verify that comprehensive commissioning is completed at the component equipment level and, more importantly, at the systems level.
- Allow added time in construction schedules to fine tune systems operation to actual occupancy and climatic conditions. System operating parameters, of necessity, are theoretical at the time of design and installation and need to be adapted to actual conditions in order for peak energy efficiency to be achieved.
- Within the second year of operation, begin ongoing commissioning and conduct an energy audit. Engage operations staff in this effort to maximize additional energy saving opportunities.
Installation of and keeping the underfloor air system space clean proved to be a real challenge due to the debris generated by some of the historic preservation activities, such as plaster restoration. There were concerns about leakage and energy loss through cracks in the floor, perimeter, and beams. A high-efficiency, ceramic insulation coating developed with NASA technology was applied to the floor and walls of the plenum at a strategic point in the construction, providing a new and clean coating of known characteristics, a thermal barrier to the exterior wall and floor slab to prevent thermal bridging, and an additional sealing coat for reducing air leakage. But being innovative, we didn’t have other projects or documentation to explain why the ceramic was needed, and so we had to explain it based on the physics and benefits that it would hold. Also, at the time of this project, there was no real software to guide underfloor air distribution design, so that was a challenge, as well.
In addition, there wasn’t really enough time to accommodate commissioning during the time available. As a result, the initial energy performance was very poor. This got us very seriously into the re-commissioning and energy utilization and commissioning of sensors and things not working properly, but also more systemic issues looking at the overall HVAC. For example, we found that there was high natural gas use, which was also increasing the cooling use because it was being used for reheat. We addressed the simultaneous heating and cooling aggressively – we looked at individual calibration of underfloor pressures and were able to lower the flow to meet certain climate and occupancy conditions. We didn’t anticipate this in design, so re-commissioning was very beneficial.
What key moments adjusted the project’s direction or outcomes?
One of our "aha" moments dealt with our continual assessment of our LEED strategy. The owner did not come to the table at day one looking for a LEED Gold or Platinum building; they wanted it to be sustainable and LEED-certified, and through the process, we would determine what would be a realistic level of expectation. With our original LEED checklist, we discovered that Silver wouldn’t be a problem at all. As we continued to work as the team, the question arose, "What would we need to do to get to Gold?" With some tweaking of strategy, we demonstrated that there would not be a lot required in terms of additional money, effort or compromises to do this, so we adjusted the design accordingly. Then, the owner asked what it would take to get to Platinum. Here, we looked harder, and determined that is was again very realistic with no additional money or compromises. This was the most gratifying series of "aha"s – working together as a team to realize that Platinum was a very attainable goal. The team immediately became committed to changing the project's parameters and expectations. In addition, initially, we were only focused on attaining LEED for Core and Shell, and the owner came back and said maybe should look at LEED for Commercial Interiors, as well - and again, we realized that this was very doable and everyone was fully committed.
I suggested LEED for Existing Buildings as a next step in greening The Christman Company. People were excited about the double-Platinum. Using LEED as a tool to green this building and all of our operations would be good, and we decided to go for LEED for Existing Buildings on the headquarters before the first year of operation was up.
A key realization, after construction, was that the building wasn’t performing energy-wise as modeled and so there was a need to go into a re-commissioning effort. This was a pivotal time and an important decision to redeem the fact that it was suitable for LEED Platinum and show that LEED for Existing Buildings had measurable results. The decision to go ahead with LEED for Existing Buildings was critical, with energy savings as one of the drivers that got us to move in that direction.
How has this project influenced your approach to other projects?
This project did not change how Smith Group does work, but it reinforced the way that we get work done. What we learned from this project was that the integrative approach to design, common and well-understood goals and objectives, and the entire team sharing in project authorship are keys to success.
This project reinforced how setting clear project goals, actually using an integrated design and construction process, and using the LEED checklist to monitor how the integrated team is doing at each stage in the design process (rather than "chasing" LEED points) can result in higher LEED certification levels at minimal additional cost. Having proved these concepts on this project, The Christman Company now encourages the use of this approach on all our projects.
Through this process of developing and working in our project, the commitment of the senior executives of our company to green construction and our own green practices definitely grew. We now really see green construction as a strategic way of growing the company in terms of pursuing business and truly committed to be green in everything we do. When people visit, it is a living example of what we do and how they can do it, too – achieving productivity and efficient cost operations.
So, what do you think? Help us improve our new LEED project library by completing this short survey.