Integrated Design

Market Challenge

Integrated retrofit design has been shown to provide better value for building owners when they align construction and design impacts across multiple systems. However, the process for achieving an integrated design is not well understood in the commercial building market and currently requires specialized skills to leverage models, many of which do not share information seamlessly. One of the greatest challenges when using building information modeling (BIM), is dealing with multiple file-exchange formats and platforms that lack interoperability. Retrofit teams for smaller projects do not typically have a staff of knowledgable modelers and design professionals capable of supporting an integrated retrofit project, nor do they have the time or resources to support the use of multiple modeling tools required for implementation.

Regardless of building size, there is also a need to make existing models more robust to handle integrated design and to improve the visualization of modeling data for design teams. While the Department of Energy has developed sophisticated modeling tools (e.g., Energy Plus, OpenStudio, Radiance) that have made integrated design easier, additional functionality is necessary. For example, it is difficult to model lighting design energy performance in a building, taking into account daylighting. Information from the models can be more effectively used by designers if the information is visualized, but few simple visualization tools are available that allow teams to optimize the design and collaborate around shared information.

Approach

CBEI researchers conducted a gap analysis of processes and tools currently applied to integrated design to identify specific research focus areas. Three interconnected paths were developed. The first path involved mapping steps across the design process, taking into account multiple system processes and needs. This path identified the need for guidance on how to approach integrated design as well as the need for specific tools that are critical for integrated design. The second path focused on challenges related to the lack of interoperability among BIM tools and a growing demand for additional modules in existing tools. An important part of this path was to support the use of open standards among existing design and analysis tools to better integrate and connect design information. Additionally, CBEI improved the Department of Energy’s Airflow Network, EnergyPlus and OpenStudio with additions that better model airflow, daylighting and lighting design, and occupancy. The third path was to improve the ability of design teams to visualize modeling results. The growing availability of three-dimensional modeling tools allows a virtual reality approach to integrated design, which helps identify potential issues before they impact project cost and schedule.

IMPACTS

Integrated Process

BIM Planning Guide

CBEI researchers delivered a concrete stepping stone for real estate development teams implementing BIM strategy and planning through the life-cycle of a project. The BIM Planning Guide provides a structured procedure for creating and implementing a BIM Project Execution Plan for Energy Retrofits. The BIM Planning Guide provides a five-step structured procedure to facilitate planning and communication among project team members during the early phases of a project. Since the best method for BIM implementation is unique for every project, each team must effectively design a tailored execution plan by understanding the project goals, the project characteristics, and the capabilities of the team. The BIM Planning guide supports the entire life-cycle of a project, including post-construction follow-ups considering measurement, verification, and performance monitoring, enabling maximum long-term benefits.

The Advanced Energy Retrofit Roadmap

CBEI researchers recognized that the market lacks process-based products which offer the architecture, engineering and construction industry a comprehensive action plan for applying Integrated Design principles to advanced energy retrofits in small/medium buildings. The investigators developed a set of step-by-step guidelines and protocols that organizes the design and construction process needed during a retrofit project, geared to building owners, their staff, and the retrofit project team members. The Roadmap consists of a three-tiered suite of guides: The Integrated Design Advanced Energy Retrofit Roadmap Overview; a detailed Retrofit Roadmap Reference Manual; and a set of four Project Team Guides outlining the activities involved in projects at four levels of effort — Lite, Partial, Substantial and Comprehensive.

Simulation Modeling & Interoperability

BIM DATAHUB

BIMdatahub

CBEI researchers developed a database for building information modeling (BIM Datahub) for storage, retrieval, and exchange of standards-based building data to support design tool integration. It serves as a shared knowledge resource for information about a facility, forming a reliable basis for decisions during its lifecycle from inception onward.

BIM removes issues common to both new construction and facility improvement projects, such as questionable communication between team members, difficult visualization of end results, unrealistic user expectations, and post-construction complications. The BIM Datahub makes it possible for design teams to more easily apply BIM in retrofits.

HIGH PERFORMANCE COMPUTING TOOLS & APPLICATIONS

CBEI researchers delivered substantial value to DOE’s suite of tools for building energy modeling (BEM). CBEI developers demonstrated an advanced computational method for simulating the air-flow network and associated energy use in a building. CBEI successfully implemented new structural variables and atmospheric conditions to existing tools, and delivered a capability for accurately assessing design impacts on air-flow based on this implementation of Fast Fluid Dynamic (FFD) modeling.

CBEI delivered an optimized module solution for implementation in the Radiance simulation tool. Enhancements to the model enable more informed lighting design and energy savings estimates, when taking into account key design elements such as lighting layouts and daylighting configuration, combined with installed sensing and controls technologies. This allows the user to maximize energy savings potential based on building design inputs. Enhancements to OpenStudio and Radiance were embedded into the core OpenStudio application platform and Building Component Library measures.

CBEI developed a calibrated occupant behavior module for incorporation into EnergyPlus, which delivered an informed feature to simulated occupants’ influence on building performance. The inclusion of occupant related data assumptions is important to enhance BEM tool capabilities, as research has proven occupants influence building performance through; temperature set-points, schedules, and adaptive behaviors.