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.)

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.

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.