Preserving Our Natural Resources Through Design, Maintenance, and Commissioning
So many teams focus on first cost - the cost to design and construct a facility. User demands often take precedence over O&M considerations, as does the architect's creation of a visual environment. The sacrificing of service and maintainability for visual or space programming is contrary to the principles of green design and sustainable development.
While we must all live within our budget, we must do so in a balanced approach. The great architectural statements that incorporate daylighting and solar control features for increased energy efficiency are of little value if the building exterior cannot be maintained or the occupants are subjected to poor indoor environmental conditions.
Howard Stussman, editor-in-chief, Engineering News Record (ENR), stated in the April 2000 issue of ENR "Members of the building community are complaining about the deterioration in quality of construction documents."
Moisture buildup in building interiors is the cause of 80% of the IAQ claims filed today. The paths of moisture into a building include rainwater intrusion, vapor transmission, and incorrect hvac operation or design. The consequences of moisture in buildings is significant and well documented.
Owners who have had the unfortunate experience of having a sick building have been burdened with repair costs that often exceed the original cost of the building.
Materials used to construct the building that are contaminated by mold and mildew growth must be removed and sent to landfills, energy and new resources are expended for the repairs, building occupant productivity is stopped, and the efforts by all involved does not fit the principles of sustainable development.
The shame is that these failures can be avoided without affecting the project schedule; the solutions add only minor costs, if any, to the project, and they result in lower total cost of ownership over the life of the building.
Commissioning can save an owner from the problems that cause poor indoor environments, poor building performance, expensive repair and operating costs, and save society from many negative environmental impacts associated with building failure.
Commissioning is often associated with only hvac and electrical systems, but building envelope commissioning is an essential component of whole-building commissioning and one of the keys to the long-term success of a project. The principles of sustainable development contained in the US Green Building Council's Leadership in Environmental and Energy Design (LEED[tm]) rating system are based on preserving and utilizing our natural resources efficiently, increasing our productivity and enjoyment of our interior spaces, and minimizing environmental impacts.
Case StudiesIf mankind is going to survive and not follow the path of the dinosaurs, we must change how we use our resources. In order to accomplish this, we must understand the impact of our actions and change our daily activities so as to change the direction in which we currently tread.
There are examples throughout the building community of system failures that could have been prevented by incorporating whole-building commissioning. The following are field observations that show design and construction errors that have resulted in moisture intrusion, indoor environmental quality problems, occupant complaints, and significant costs to the building owners and the businesses occupying these buildings.
The intent of these examples is not to draw attention to the specific buildings or the teams that delivered them but to highlight why the typical delivery system for facilities must be changed so that the building community maximizes the efficiency of the resources used to construct, operate, and maintain a facility, while enhancing the productivity of the occupants. It is this author's experience that good designers and contractors are not immune from the examples contained in this article and many of the examples shown are in Class A facilities that were designed and constructed by firms with excellent reputations.
Figure 1 shows the roof of a building that was designed by a firm that employed sustainable development principles of daylighting and exterior solar shades to maximize energy efficiency but missed the practicality of maintainability. As you can see, the only access to a significant portion of an entire elevation is through a leap of faith across one roof to the second roof that is 400 ft above the street and then manhandling an approximately 350-lb davit across this same gap in order to make repairs to the building envelope.
This is only one of many access problems that were encountered in trying to access areas of the building envelope when evaluating the reasons for extensive moisture intrusion problems in the building envelope. Making such access difficult helps to ensure that the cost of solving such problems as well as making repairs is delayed because of the increased difficulty and the increased cost.
Figure 2 shows rainwater migrating through an exhaust plenum. You will note the designer thoughtfully placed a drain in the plenum for such purposes and the contractor followed through with installing the plenum in accordance with the designer's intent, but the result is still rainwater intrusion into the building. Both the good intention of the designer and the contractor are evident, yet problems from this moisture intrusion resulted in IAQ concerns, building occupants with health problems, and unanticipated costs to the owner.
Figure 3 shows a section of chilled water piping removed from a problem building where moisture in the building was being generated from the chilled water system resulting in wetted ceilings, IAQ complaints, and above-average employee absenteeism. The interior surface of the pipe in Figure 3 shows very little deterioration and is a testament to the operational staff's maintenance of the chemical treatment system. Figure 4 is a closeup of the same chilled water system with extensive deterioration of the pipe's exterior from the collection of moisture in the pipe insulation, causing premature failure of the chilled water system.
Figure 5 shows the same problem of moisture-saturated insulation except on an air distribution system in a different facility. The causes of this type of failure vary from inadequate insulation thickness, inadequate vapor barriers, inadequate sealing of insulation seams, high interior building humidity, etc.
In these two facilities, high interior humidity readings were recorded, and the insulation type specified and installed does not perform well in such conditions. We have all seen where insulation around piping and duct systems has been damaged because the only path to access areas needing service is over unprotected insulation systems. These conditions lead to premature failure, increased operating costs, higher environmental impacts, and reduced occupant productivity.
Philosophy of Green DesignOne of the key elements of sustainable development and green design is the efficient use of our natural resources. As such, we must maximize the useful service life of the materials used to construct a facility through good design, installation, maintenance, and operation. While this sounds easy, it is not. Buildings are more complex today than ever before, demanding performance verification of the building envelope, mechanical, electrical, plumbing, and specialty systems to help ensure their efficient operation and a long useful service life. Inadequate operation and premature failure of any of a building's systems have significant impacts on all of us.
These effects extend well beyond the financial impact to the building owner to create demands on most of our precious natural resources. These impacts include fuel costs for mining, processing, manufacturing, transportation, electricity for installation, landfill waste, pollution, workplace comfort, employee/company productivity, and our ability to support mankind to name just a few. Green design and the principles of sustainable development encompass all aspects of our environment, and how we utilize these resources will determine if mankind survives.
The urgency of changing the way mankind is currently consuming natural resources is probably best illustrated by Paul Hawken, and Amory & L. Hunter Lovins in their book titled Natural Capitalism in which they write, "Humankind has inherited a 3.8-billion-year store of natural capital. ... At current rates of use and degradation there will be little left by the end of the next century." Many of our practices must change; development, operation, and maintenance of facilities is only a part of the total picture, but it represents a significant impact to the environment.
Whole-building CommissioningThe LEED rating system encourages whole-building commissioning. Commissioning can be the cohesive glue that binds the efforts of the designer's vision with the contractor's implementation and helps ensure that the owner gets a facility that will operate efficiently, have a lower total cost of ownership, and provide the indoor environmental quality the occupants want.
The commissioning process accomplishes this through two distinct and separate phases. The first is design phase commissioning which is a process that provides the owner a second pair of eyes in evaluating the design. The second is construction phase commissioning that monitors the construction activities and verifies performance of the systems being commissioned.
Both types of commissioning provide tremendous value to the owner, help lower the designers' and contractors' risk, and significantly improve the quality of the facility and its maintainability. Owners and project teams unfamiliar with commissioning currently, inaccurately view commissioning as an added cost.
Commissioning does initially add a line-item cost to a project, and there are always budget challenges that affect all projects, but often the cost of commissioning is offset by reducing changeorders, construction delays, and savings from VE opportunities that do not compromise the performance, maintenance, or useful service life of the building or its systems. Identifying problems early in building envelope and MEP design and construction has historically proved to lower construction costs by correcting problems early and preventing changeorders and construction delays.
Sustainable DevelopmentCommissioning can assist a project team in accomplishing many goals toward sustainable development. It is time for the building community to embrace what whole-building commissioning can do for an owner, designer, and contractors, and to use the commissioning process to lower not only first cost but long-term total cost of ownership.
By using the commissioning process, contractors and designers working with the commissioning firm will address problems when it is most cost effective to all, during the early stages of construction. Contractors will learn that they can tighten their bids because there will be fewer warranty callbacks because the systems' performance were verified before they moved off the job, and any problems identified were addressed at the most efficient period - when materials, resources, and equipment are already onsite.
Owners will have lower maintenance costs, happier tenants, and greater returns on their investments for longer periods of time. Business will prosper in a world economy because we are more efficient with our resources. Occupants will be happier and more productive. Insurance companies will be pleased because there will be fewer construction-related lawsuits, which will make the lawyers unhappy, but we can't please everyone.
The incorporation of these principles demands that we carefully determine how to cut project costs to reach a specific budget in order to make wise tradeoffs in system alternatives, finishes, and materials selected for a project as well as ensure that the materials and systems perform to their expect levels. Commissioning can provide the process to accomplish these goals.
Avoiding Building FailureThere is case study after case study documenting the cost of building failure due to problems being designed and constructed into a project. The vocal advocates of commissioning are those owners who had the misfortune of owning a building that has failed or by owners who incorporated commissioning and received value from the commissioning process.
Most of us buy insurance to protect ourselves in the event of a loss. Building commissioning is a process that, like insurance, can provide a blanket that helps shield the owner, contractor, designer, and occupant from expensive losses that result from building system failure due to design and construction problems.
As commissioning becomes a typical practice for projects, it will lower the total cost of construction. Contractors will have fewer warranty callbacks. Owners will receive a better set of construction documents and tighter bids. Designers will be involved in fewer lawsuits.
Whole-building commissioning that includes the building envelope and mechanical and electrical systems is an essential part of bringing a green design to fruition. The sooner we incorporate the principles of sustainability, the easier it will be to save ourselves. At some point we will all be forced to adopt the principles of sustainable development and green designs or reduce our standard of living or cripple our civilization in a war over materials and resources. ES