A Workflow for Early-Stage Architect-Engineer Collaboration

An earlier version of this article appeared on www.sefaira.com and on the SketchUp Blog.

It’s the paradox of early design: the most important decisions are made when architects have the least time to evaluate them thoroughly or engage with the broader team. And yet, early collaboration can unlock significant benefits for the client and design team.

Adding to the complexity are the number of parties who should ideally be involved in early decisions. They typically include:

• The architect, who makes most of the early design decisions, and is the primary contact with the client, responsible for communicating ideas and recommending an approach.

• The mechanical engineer. Architects often look to engineers for early feedback on performance. But typical engineering software is not designed for early-stage analysis, so engineers are hard-pressed to keep pace with frequent design changes.

• The sustainability specialist. Most architecture firms an in-house specialist, or team of specialists, with special expertise in building performance. But like the engineer, they struggle to provide feedback quickly enough.

So how can the design team collaborate in these harried early days — without duplicating work or holding up the design? While each firm is different, below is a basic early-stage workflow and division of responsibilities. (This workflow takes full advantage of Sefaira’s collaborative capabilities, but is general enough to apply broadly.)

The Early-Stage Workflow

1. Establish performance goals — architect. The architect works with the client to establish performance goals related to energy, comfort, daylight, energy cost, or other criteria. Part of this step is making the client aware of what’s possible. For example, the client may be interested in occupant productivity, but unaware of the link to daylight and comfort.

2. Establish metrics and benchmarks — specialist. The sustainability specialist helps to translate the broad goals (e.g. “good daylight in office spaces”) to specific metrics and targets (e.g. “Spatial Daylight Autonomy of 55%”). These are documented in the Owner’s Project Requirements (OPR).

3. Set up the baseline — engineer. The baseline case is the “control” against which design options are compared. For example, the baseline for many energy simulations is ASHRAE Standard 90.1. These inputs can be set up in Sefaira before the architect begins design. Having the engineer or specialist involved in this step ensures accuracy and acceptance of early results. A generic 3D model can be used at this stage to generate initial information about the building’s likely energy profile and potential strategies the design team should consider.

4. Conceptual design studies — architect. With the baselines and targets defined, the architect can freely explore early design moves: building form, program layout, façade design, floor-to-floor heights, and the like. Designers can be trained to quickly create study models that can be used for design, analysis, and presentation. For more complex simulations they can lean on the specialist for support.

5. HVAC studies — engineer. Once a smaller set of options is defined, the architect uploads the designs to Sefaira and shares them with the engineer. The engineer explores HVAC system options and their interactions with the envelope. Early sizing studies can help reduce size and capital cost of systems — one of the key benefits of early collaboration. The architect and engineer may go back and forth several times at this stage to work out the design.

6. Envelope optimization — specialist. When the schematic design is defined, the specialist can assist in further optimizing and fine-tuning envelope assemblies, shading elements, and façade design. Depending on the project and firm the architect or engineer may also assist in this process. It can be helpful at this stage to maintain a “smart model” that can be analyzed at any point.

Design teams that have implemented this type of workflow have reported improved architect-engineer relationships, better communication, and the ability to arrive at a solution more quickly. Architects are better positioned to communicate with their clients about performance.

Who Builds the Model?

Who has the responsibility for creating the 3D geometry for analysis? We’ve seen a few scenarios work:

Architect creates the 3D model. This allows the engineer to respond very quickly, removing one of the major obstacles to early-stage collaboration. It also means that the model can stay up-to-date with design changes. But it requires that architects are able to create appropriate models.

Engineer creates the model. This gives the engineer the ability to ensure that the model is created correctly, but can slow down the feedback process and increase costs.

Architect creates model, and specialist or engineer checks & uploads. This hybrid solution gives the architect freedom to explore, but provides quality control at key points in the process.