Virtual Design and Construction at Hathaway Dinwiddie

Starting in 2006, Hathaway Dinwiddie has transitioned company-wide to a model-based estimating workflow to improve transparency and substantially enhance the accuracy of our estimates. Now deployed on 90% of our estimates, from partial floor tenant improvement projects to large-scale multi-building campus developments, our in-house estimators create Revit models to derive the quantities upon which they build their estimates.

Transitioning to the methodology of quantifying scope in BIM now requires all of Hathaway Dinwiddie’s estimators to create delivery models for every project, at every design milestone. This prodigious output of in-house models –numbering in the thousands – provides our estimators with highly detailed quantity take-offs and a visualization of the scope for extremely accurate cost estimates – while significantly enhancing the value of our cost estimating effort.
Beyond our ability to provide highly accurate estimates to our clients, having a model-based estimate allows us to quickly communicate with owners and design teams to find ways to achieve a client’s targeted value – collaborating with the team to visually identify alternatives and evaluate them.

Preconstruction

Concurrently with our model based estimating effort during preconstruction, we work with our superintendents and project managers to streamline the logistics of the construction process. Starting in preconstruction, we work to identify drive aisles, emergency access, lay down areas, and materials zones in conjunction with building our construction schedule. Continuously checking our schedule assumptions against our logistics plans, and helping them inform one another as the project progresses, is a key part of our ability to maintain our construction schedules.

BIM Coordination

In 2007, Hathaway Dinwiddie met with major trade contractors and outlined a virtual coordination workflow that would utilize the BIM delivery models from the estimators coupled with 3D architectural and structural design models as a background for MEP design, detailing and coordination. This 3D alternative to conventional light table and 2D CAD based methods became a reality in 2008 when we executed our first design-assist, prefabrication and construction project in a 3D environment. This collaboration effort with designers and builders resulted in a complete and coordinated set of construction bid documents and allowed for over 98% MEP and steel prefabrication, increasing field productivity and value to our client.

Today, Hathaway Dinwiddie continues to manage our BIM coordination efforts in-house, deploying BIM Engineers and MEP Coordinators to manage the detailing process, support the owner and design team, and use their expertise and position to ensure a high-quality product is delivered to our clients. Since our first deployment of the BIM Coordination process, we’ve continued to improve by creating a comprehensive week long training course for our BIM Engineers, streamlining our workflows by automating the assignment of clashes to particular trades, and deploying standard templates and models to ensure consistency across our BIM operations company-wide.

As we look towards the future, we continue to push industry boundaries by writing custom software plugins to streamline our internal processes, and give back by teaching new industry leaders our methods at a variety of universities. Key to our efforts is a new focus on “Big Data.” Newer versions of the software tools we’ve written are now starting to collect data about our BIM coordination efforts. Tracking these metrics in real-time will help us improve our process even more, while simultaneously making it more transparent.

Notes on Virtual Construction

Notes on Virtual Construction: Planning a Cutting-Edge Performing Arts Center

The SFJAZZ Center is a 3-story performance venue that houses a 700-seat auditorium, educational space, a restaurant, two bars, and office space for the non-profit that bears the building’s name. This world-class, state-of-the-art facility was specifically created for jazz performance – the only such building of its kind in the United States. The Center is LEED Gold certified.

They say that in jazz music, it’s the notes you don’t play that matter. To riff a bit on that old adage, we believe that the better you understand a building before getting out in the field – that is, the more ‘notes’ of the building that you’ve ‘played’ in preconstruction and planning – the better off the job will be.

Purposeful use of Building Information Modeling was a major contributing factor in the successful construction of the SFJAZZ Center. The building houses an immense amount of program within a small container. As a result, the complexity of scope requiring cost estimation and buyout was well above that of most projects, as were the demands to coordinate that scope in the field.

During preconstruction, Hathaway Dinwiddie virtually constructed the building more than a half dozen times, becoming intimately familiar with the details and assemblies, and sharing data and visualizations with project stakeholders and the trade community. Data from the model drove the cost estimates at each stage, and allowed for transparent tracking of the budget as major systems developed through the course of design. When requirements for value engineering arose, cost studies were performed rapidly, in many cases with accompanying visuals, and as a result the decision-making process for the project team was simplified.

As we transitioned to the field, our MEP coordinators took control of the BIM process, with a heavy emphasis on trade coordination. The Center melds together numerous high-tech systems: main building electrical, plumbing, and an underfloor HVAC concept; theatrical lighting; A/V; security; voice and data cabling, etc. We worked with our trade partners in these and other disciplines to complete detailing in 3D and ensure that fabrication and installation would be successful, which was critical on a fast-moving project with a very firm completion date. Building projects are not the same as memorable jazz solos – when we are in the field, we prefer to minimize the use of improvisation.

The capabilities we brought to the project, along with our discipline in applying them, resulted in a sophisticated, architecturally exquisite building completed on time for its scheduled grand opening celebration. And we have to say – for those of us sitting in the audience during the opening week performances – the notes that we heard coming from the stage definitely mattered.