Most owners sign one design contract and assume they have hired one designer. They have not. On a typical new church, office building, or hotel, the architect and engineers who work under that one contract include a structural engineer, a mechanical engineer, an electrical engineer, a plumbing designer, and very often a civil engineer, each running their own calculations and sealing their own sheets. By the time the permit set goes to the city, a large share of the drawings carry a professional seal other than the architect’s. That is not a sign that something went wrong. It is how buildings get designed, and understanding how that team is assembled and held together explains a great deal about why some projects run quietly through construction while others generate a steady stream of surprises.

Does the architect hire the engineers?

Usually, yes, but not all of them, and the split matters. The standard owner-architect agreement most projects in this country use, the AIA’s B101-2017, says in Section 3.1 that the architect’s basic services include “usual and customary structural, mechanical, and electrical engineering services.” Those engineers are retained by the architect, listed by name in Section 1.1.11 of the agreement, and paid out of the architect’s fee. From the owner’s side, that means one contract, one point of responsibility, and one firm whose job is to make sure the structural drawings, the ductwork, and the light fixtures all describe the same building. When a question comes up about the roof framing, you call your architect, and your architect calls the structural engineer.

The same agreement assigns two things to the owner. Section 5.4 requires the owner to furnish a survey describing the site’s boundaries, easements, utilities, contours, and adjoining streets, and Section 5.5 requires the owner to furnish geotechnical engineering, which means soil borings, bearing capacities, and written recommendations. The logic is that these describe the property itself rather than the building, and they exist independently of any design. The architect is entitled under Section 3.1.2 to rely on them, which is exactly why they need to be right and why they need to arrive early. We have written before about the investigation that should happen before you buy the land, and the survey and soils report are the two documents that carry that investigation forward into design. A structural engineer cannot size a foundation without knowing what the soil will hold, and a civil engineer cannot design a parking lot without knowing where the water goes.

Everything else falls somewhere in between. Civil engineering, landscape design, acoustics, audio and video systems, theatrical lighting, commercial kitchen design, and low-voltage technology are commonly treated as supplemental or additional services. Sometimes the architect brings those consultants under its own contract, and sometimes the owner hires them directly. Either arrangement can work. What does not work is leaving the question unanswered until a church has signed a contract with an audio and video integrator who has never seen the structural drawings.

Who is actually at the table

The structural engineer decides how the building stands up. That begins with the geotechnical report and the loads the adopted building code requires for your location, including wind, snow, and the weight of the people who will fill the room, and it ends with foundations, columns, beams, joists, and connections. In a church, the long clear span over a worship room with no columns in the sightlines is a structural decision before it is an architectural one, and it shapes the roof profile, the ceiling height, and where heavy equipment can and cannot hang.

The mechanical engineer designs heating, cooling, and ventilation, and in most buildings the mechanical systems take more space above the ceiling than anything else. A sanctuary is a hard mechanical problem because its occupancy swings from nearly empty on Tuesday afternoon to full on Sunday morning, and the outdoor air the code requires for a full house is very different from what an empty room needs. The plumbing designer, often working within the same engineering firm, sets fixture counts that the code ties to occupancy, sizes the water and sewer connections, and coordinates gas service where there is any. The electrical engineer sizes the service from the utility, lays out power, lighting, emergency lighting, and fire alarm, and increasingly coordinates with the utility on transformer lead times that can stretch well beyond the design schedule.

Fire sprinkler systems are a special case. In much of the country the engineer of record writes a performance specification and the detailed sprinkler layout is designed by the fire protection contractor after bidding, based on a water flow test at the nearest hydrant. That arrangement, called delegated design, also applies to items like pre-engineered wood trusses, metal building systems, and some steel connections. The engineer of record sets the criteria, the contractor’s engineer designs to them, and the architect and engineers review those designs through the submittal process during construction to confirm they meet the intent. Nothing about delegated design is a shortcut, but it does mean some of the engineering on your project is completed months after the drawings are issued.

The civil engineer handles everything between the building and the property line: grading, stormwater detention, paving, utility connections, and the site plan the city reviews. On many suburban church and commercial sites, the civil work is what the planning commission spends the most time on, because stormwater and traffic are what the neighbors notice. Specialists fill out the rest. An acoustician shapes how speech and music behave in a worship room. An audio, video, and lighting designer plans the rigging, the screen locations, and the dedicated power and cooling that a modern stage requires. A food service consultant lays out a commercial kitchen so it passes health review the first time.

What coordination actually means

Every one of those professionals is competent within their own discipline. The risk on a building project rarely sits inside a discipline. It sits at the boundaries between them, where a main supply duct needs to pass through the same space as a steel beam, where a rooftop unit weighs more than the joists beneath it were designed to carry, where a ceiling height promised in the rendering leaves eight inches for the ductwork that needs fourteen, or where the light fixtures and the projection screens want the same piece of ceiling. Most of what goes wrong between disciplines goes wrong at the edges, where one consultant’s work ends and another’s begins. No individual engineer owns those edges. The architect does.

In practice, coordination is a discipline of timing and repetition. At the start of schematic design, the architect sets the building’s basic geometry and floor-to-floor heights with input from the structural and mechanical engineers, because those two decide how much room the structure and the ducts will need. Through design development, each consultant develops their systems in a shared model, and the team checks them against each other at defined points, looking for physical conflicts and for the less visible ones, like a fire-rated wall that a duct crosses without a fire damper or an equipment room too small to service. In construction documents, every sheet is checked against every other sheet before the set is issued. We covered why the design phases take as long as they do in an earlier post, and a large share of that time is this work, invisible to the owner when it is done well.

The industry is candid that it never gets this perfectly right. Even a well-run team issues drawings with a few conflicts that the coordination reviews missed, which is why contractors submit requests for information and why owners carry a contingency. A study by Dodge Data & Analytics with the AIA Large Firm Roundtable put the expectation plainly.

That 2014 survey of owners, architects, and contractors is worth reading for its other main finding as well. Owner-driven issues, such as unclear requirements, accelerated schedules, and program changes, ranked as the leading drivers of risk, and better communication and integration among the project team ranked as the most effective remedy. Coordination between engineers is one form of that integration. The other form runs between the design team and the owner, and it is where many of the hardest coordination problems actually start.

Where the seams show

Consider a composite of a situation we have seen in several forms. A growing congregation is well into construction documents for a new worship center when its media team, working on its own, signs with an audio and video integrator. The integrator proposes a large LED wall behind the stage, a lighting truss over the platform, and an equipment rack room off the stage. Each item is reasonable. None was in the program the design team was given. The LED wall needs structural support and dedicated circuits, the truss needs rigging points the roof framing was not designed to carry, and the rack room needs cooling that runs around the clock. All of it can be designed, but now it is being designed late, by people who have not been in the coordination meetings, against drawings that were nearly finished.

The standard agreement anticipates this. Section 5.8 of B101 makes the owner responsible for coordinating the services of its own consultants with the architect’s, and the practical meaning is that any consultant the owner hires directly needs to be introduced to the design team early and given the drawings to work from. The same principle applies to the surveyor and the geotechnical engineer, to a technology vendor, and to a denominational or franchise design standard that sets requirements the design team needs to see. Each one is a source of information the engineers are relying on. When it arrives late or incomplete, the cost shows up as redesign, as a request for information during construction, or as a change order.

Renovation projects add their own seams. In an existing building, the engineers are designing new systems that must connect to old ones, and the condition of what is hidden above ceilings and inside walls is often unknown until someone opens them. That is why renovation design leans so heavily on field verification, and why an existing building’s original drawings, if anyone can find them, are worth more to an engineering team than most owners realize. The code analysis that opens every project also drives a good deal of renovation engineering, because changing how a building is used can trigger requirements for ventilation, fire alarm, sprinklers, and accessible restrooms that the existing systems were never designed to meet.

At UNITE, we treat the engineering team as part of the design from the first meeting rather than a set of specialists brought in to fill in the drawings once the architecture is settled. Across more than 1,000 church projects and a long list of commercial and hospitality work, we have learned which questions the structural and mechanical engineers need answered before the first floor plan is drawn, which owner-side consultants tend to arrive late, and where the seams between disciplines are most likely to open. Our job is to hold those seams closed, so that the building you see in the rendering is the one the structure can carry, the systems can serve, and the contractor can build without a stack of questions. If you are starting to assemble a project team, or wondering who should be on it, we would be glad to talk it through with you.