Interdisciplinary Coordination of Construction Documents

Gaps between design disciplines are a common cause of construction change orders. In some cases, the consulting disciplines' standard practices may generate a gap. For example, the electrical engineer may establish an electrical scope of work that "stops" 10 feet outside the building, while the site civil engineer may expect (and indicate on the site drawings) that the electrical contractor will provide power to a sewage lift station that is 15 feet outside the building. Unfortunately, it is quite possible that neither the electrical engineer nor the civil engineer will become aware of this gap in electrical service until the contractor submits an RFI.

Similar gaps can occur between plumbing and site trades, between mechanical and general building trades, between structural steel and miscellaneous metals trades, and between other trades. In most cases, proactive coordination by the project architect during the construction documents phase can help to minimize these gaps."Proactive" coordination means getting involved in finding and highlighting possible gaps and managing document revisions to eliminate the gaps by conferring with the related disciplines, considering applicable trade practices and regulations, and assigning responsibility to the most appropriate party. (It's usually not enough (and not really proactive) to simply tell the consultants to work it out between themselves.)

A Catch 22 Product Specification

Specifications occasionally include unintended contradictions, and in some instances they are related to schedule.

Not long ago, I reviewed a specification for roofing that included a requirement for a particular "ice and water shield" product and allowed no substitutions. The application requirements for the product included a minimum ambient temperature of 40 degrees F. That looked good from a quality control perspective, but the schedule for this fast-track, multi-building project in snow country required construction during the winter, when temperatures were expected to be well below 40 degrees F, and neither the schedule nor the budget allowed for temporary tenting and heating of whole buildings. As a result, in order to meet the schedule, the contractor had to apply the product under conditions that were not recommended by the manufacturer and were not in compliance with the specification.

Building Science and the Risks of Experimentation

Science is experimental; it consists of hypothesis and experiment. The path to success can be littered with experiments that fail. Scientists learn to expect failure along the way and to live with experimental failure as the cost of progress. Scientific design is experimental, and it is accompanied by an expected risk of failure.

The growing popularity of building science today brings increased risks of experimentation to the mainstreams of the building industry and the practice of architecture.

Historically, building design decisions were based on long established and proven practices and material selections. Expectations of reliability rested on proven performance over years or decades or - in some cases - centuries. The practice of experimentation was left mostly to the fringes and outliers. Main-streamers tended to avoid products and systems that lacked a good track record. Established building technology was a focus of learning and skill building; architects and builders could expect to learn from a previous generation and practice for decades with a building technology that would remain essentially the same.

More recently, we have seen and become obsessed with an increasing pace of change. Many equate faster with better, making decisions based on the latest available product or on predictions of the next invention or innovation - perhaps even with a belief that it must be better simply because it is new and not established. However, this kind of experimental approach to building design and construction dramatically increases the risk of building failures, in large part because it discredits time-tested performance and avoids or dismisses time-consuming consideration of the multiple roles played by building materials and the roles played by parties in the construction process.

Valid interest in (and popular incentives for) conservation and quality of resources and processes may have led to a willingness on the part of some to take more risks with experimentation. But questions need to be answered: Who assumes the risk? How much risk? Is there awareness and consent of assumed risk? and, If it fails, who owns the failure? Further, If it fails, how can it be considered a sustainable practice?

Construction Documents Coordination Matrix

It may look a little "geeky", but this matrix can be an effective tool for considering interdisciplinary coordination needs. The design disciplines for a project are listed across the top and down one side. The intersection points represent coordination between disciplines (e.g., between Civil/Site and Electrical). Seeing the possibilities in this format can help to minimize coordination gaps. On a given project, the extent and specifics of coordination will differ from point to point, and the design displines may also differ. Still, seeing an intersection point can prompt thoughts about needed coordination between any two disciplines. For example, where Civil/Site meets Foodservice, it may bring to mind the need to coordinate the locations of exterior condensing units with site work. Etc. Etc. Etc.

Looking at this coordination matrix, it is also easy to see how extensive coordination really is (and must be) on an architectural project. On some complex projects, coordination can be seen as a full time job in itself, from the coordination of consulting agreement scopes of work to the coordination of sub-trade scopes of work and the dotting of i's and crossing of t's in construction documents.

The 50-50 Rule

Jobs vary in the proportion of time required for technical work ("stuff") vs. people work (communication, cooperation, management, etc.). Some jobs may consist of less than 50% stuff, but most jobs done effectively require at least 50% people work. If you are doing a technical job in architecture (or most any other field), and you think that your job is 100% or near 100% "stuff" and 0% or near 0% "people", you are probably not doing your job effectively, and you are probably neglecting at least 50% (the "people" part) of your job.

When you develop drawings - plans, sections, elevations, details, etc. - and specifications, you depend on other people to understand and make effective use of those drawings and specifications to produce desirable results. Your work must effectively communicate with others, be they other designers, consultants, owners, users, permitting authorities, estimators, bidders, contractors, subcontractors, material suppliers, and others. And the value of your work - especially technical work - is diminished by the extent that it does not effectively communicate with others.

While jobs do vary in the actual proportion of "stuff" vs. "people", a good approach to a technical job is one based on a consideration that at least 50% of the job is people related. That's the 50-50 rule.

Masonry Design: Not-Quite-Through-Wall Flashing

Through-wall flashing is a common water management feature of masonry cavity wall and veneer construction. It is most effective if its outer edge is beyond the outer face of the wall and is turned down to form a drip edge and help water fall away from the joint under the flashing. It can be ineffective and result in leaks into a building if the outer edge of the flashing is concealed within the wall. In at least one case, a leak was attributed to flashing that stopped above the core holes of extruded brick. The design relied on the through-wall flashing to protect the building interior, but water which was intended to be conveyed out of the wall by the through-wall flashing was instead allowed to re-enter the wall and subsequently find its way to the building interior. Apparently, someone did not want to see the edge of the flashing coming out through the wall. At the time of construction it was common for the flashing to be coated with asphalt, and the asphalt coating - not especially attractive in any case - would melt under sunlight and over time it would drip and stain the face of the wall below. More attractive materials are widely used today, including drip edges of proprietary compositions or even stainless steel. The more attractive materials are likely to be more expensive. However, stopping the flashing within the wall may be the most expensive option of all, considering the possible costs of leak remediation.

Metal Roofing Specifications: "No Visible Oil Canning" equals Mission Impossible.

On my first visit to the job site after the roofing contractor had started installing standing seam metal roofing, the Clerk called me aside and said, "I think we've got oil canning."

I looked at the newly installed metal. It looked fine.

"Wait a while", he said. As the sky changed and the angle of the sunlight changed during the day, oil canning appeared, then disappeared, then reappeared differently. "The specs say 'no visible oil canning'," the Clerk accurately noted.

The spec writer's best intentions, possibly influenced by the designer's best intentions, were that from Day One and under any and all light conditions the metal roofing would exhibit no visible distortion. Seeing the situation in the field, a part of my mental faculties that were still intact suggested we had a problem that was more perceived than real. Over the next few days I visited and photographed a number of other projects with metal roofing - from afar, up close, and under different light conditions. These appeared to be carefully crafted installations with little or no distortion related to the installation. Yet under some light conditions and viewing angles, they all exhibited 'visible oil canning'. I put the findings into a little presentation for the client, who had been alerted to the oil canning condition by the Clerk. Following the presentation, the client was satisfied that the metal roofing was normal in terms of visible oil canning. The spec writer? Well, that's another story.

(Visit http://www.smacna.org for an October 2005 newsletter article on oil canning and information about how to minimize it.)