gbXML

The Residential HVAC Load Calculation Extension software system is a residential and light commercial HVAC load calculation software package based upon the ASHRAE 2001 Fundamentals algorithms (Chapter 28). This program is geared specifically toward the design/build mechanical contractor, design mechanical engineer, and architects.

The purpose of this software is to provide the user with total cooling and heating loads for a building so that they may properly specify the correct size HVAC equipment (whether it is a packaged rooftop unit or a boiler).

Autodesk Ecotect can measure how fundamental criteria, such as solar, thermal, shading, lighting, and airflow, will affect building performance in the conceptual and detailed phases of design. This capability to forecast building performance over time better equips architects and engineers to deliver more energy efficient and sustainable building designs.

Autodesk Ecotect is a separate program and is not integrated into AutoCAD or Revit. It does the calculations using the gbxml analysis data that is exported from the BIM model. So you need to setup your model with rooms if you're using Revit Architecture, and with spaces if you're using Revit MEP.

Below is a white paper on how to prepare your BIM model for the export to the gbxml file.

Building Performance Analysis Using Revit Whitepaper

1. Inputs for HVAC system characteristics such as supply cooling and heating temperatures, ventilation rates, fan characteristics, cooling and heating setpoints, duct sizing, and safety factors
2. Inputs for HVAC area (room) characteristics such as wall, window, roof, door, skylight, and partition areas. In addition, there are inputs for # of people, electrical appliances, infiltration, lighting, miscellaneous, exhaust, and plenum loads
3. Weather data from over 800 cities throughout the world
4. A complete u-value database for common wall, roof, window, floor, and door types
5. A complete appliance list for determining internal electrical equipment load contributions
6. Many reports including summary, detailed, psychrometric, wall/window breakdown, 24-hour load breakdown, and graphical reports
7. A feature that allows the user to export all inputs and outputs to custom Microsoft Word and Excel documents
8. Equipment selection
9. Support for both English (IP) and Metric (SI) units

Autodesk announced that the company is making two extensions for AutoCAD MEP and Revit MEP available to mechanical, electrical, and plumbing (MEP) engineers to design more efficient building mechanical systems. The MEP Analysis Extension, available as a free 30 day technology preview from Autodesk Labs, is a set of 25 utilities that MEP engineers can use to better understand how a building system will perform before it's built, ultimately helping MEP engineers reduce energy costs and environmental impact while improving the performance of building systems. The HVAC Load Calculation Extension, available for Autodesk Subscription customers of AutoCAD MEP and Revit MEP, performs peak cooling and heating load analysis for commercial buildings so that engineers can properly size HVAC equipment. Both extensions can function as stand-alone applications, but also work in conjunction with both AutoCAD MEP and Revit MEP.

http://labs.autodesk.com/utilities/mep_analysis_extension/

The MEP Analysis Extension calculates rule-of-thumb cooling and heating loads for commercial and residential buildings, calculates total R-Values for walls and roofs, determines psychrometric properties of air, and more. Running these types of calculations through the MEP Analysis Extension can help MEP engineers reduce error and waste, potentially saving energy costs, the company states. The MEP Analysis Extension also contains utilities for sizing duct work, piping, and HVAC systems, helping engineers and architects identify the most appropriate building equipment early in the design cycle.

The following utilities are included in the MEP Analysis Extension:

• Metric to English units converter
• single-state psychrometric calculations
• mixed-air psychrometric calculations
• duct sizing calculations
• ASHRAE duct fitting pressure loss calculations
• general pipe sizing
• hot/chilled water pipe sizing
• steam pipe sizing
• low-pressure gas pipe sizing
• high-pressure gas pipe sizing
• refrigerant pipe sizing
• fan cost analysis
• fan curve analysis
• pump curve analysis
• rule-of-thumb commercial HVAC load calculations
• simple residential/light commercial HVAC load calculations
• swimming pool heating calculations
• u-value calculations
• gbXML parser
• wire sizing utility
• glass moisture condensation
• life cycle cost analysis
• a super calculator for complex equations
• manage HVAC equipment lists
• manage climatic weather data

The HVAC Load Calculation Extension is a comprehensive HVAC (heating, ventilation, and air-conditioning) load calculation software tool that determines building peak cooling and heating loads based upon current calculation techniques from ASHRAE. Using the results from the software, engineers can properly size cooling and heating equipment without oversizing such equipment, which often results in wasted energy. The Load Calculation Extension works as a stand-alone application, but also integrates easily with BIM modelers such as Revit MEP.

The MEP Analysis Extension is available as a free technology preview from Autodesk Labs. Visitors to Autodesk Labs are encouraged to experiment with inventive new tools and provide feedback to the Autodesk team. The HVAC Load Calculation Extension is available to customers of AutoCAD MEP 2009 and Revit MEP 2009 on Autodesk Subscription and is subject to Autodesk Subscription terms and conditions. The extension is currently available in English only, but will operate with all language versions of AutoCAD MEP 2009 and Revit MEP 2009 software.

The extension will run through October 31, 2008.

Available as a Technology Preview feature, the Extension is programmed to expire within 30 days of installation. They are offering this extension to get feedback to help them make better products and technology, and it plays an important role in determining the future of the Extension. Tell them what you think!

Back in ABS 2007, and ADT 2007, there was a new feature that combined the architectural spaces and the engineering spaces into one space object that could be shared between both deciplines.

Click on picture to see the problem.

Asking the Architect to move their spaces into a separate xref file, rather than placing spaces in the architectual model itself might be a lot to ask but it will be the only way that engineers will be able to use spaces and zones in their engineering models. The architect can start a new file that will be just for the Architectural spaces. The Architect would xref their background into this new file containing their spaces.

With their spaces off to the side, this should free up their backgrounds to allow engineers to make your own spaces.

In the meantime, Autodesk has logged a wish request to make Rooms different from Spaces so the engineer can model the volumes we need for calculations. Architects can model their Rooms. Kind of going back to what they had in 2007, and what Revit MEP 2009 has.

The Autodesk Green Building Studio analysis tools, now available at http://www.autodesk.com/greenbuildingstudio, provide improved design insight through whole building energy, water and carbon-emission analysis, helping architects and designers to maximize building economic and environmental performance. The tools are compatible with Autodesk design software as well as software from other industry providers through the Green Building XML (gbXML) schema and can now be directly accessed from within the Revit platform for BIM with a new plug-in now available for download. Green Building Studio Inc. launched the Green Building Studio web service in 2004.The Autodesk® Green Building Studio® web-based energy analysis service can help architects and designers perform whole building analysis, optimize energy efficiency, and work toward carbon neutrality earlier in the design process. With faster, more accurate energy analysis of building design proposals, architects and designers can work with sustainably in mind earlier in the process, plan proactively, and build better. With the Autodesk® Green Building Studio® web-based energy analysis service, architects and designers can evaluate building components for impact on energy consumption as well as improve economic and environmental performance early in the design process. Compatible with Revit MEP The Autodesk Green Building Studio service is an analysis tool that interoperates with Revit® MEP and other compatible energy-analysis software and facilitates team collaboration and information sharing at all stages of design. Evaluate Energy Profiles of Building Designs Green Building Studio tools enable architects and designers to evaluate the energy profiles and carbon footprints of various building designs. Files are shared between engineering software programs and among engineers and architects early in the design cycle, making sustainable design more efficient and cost effective. With Autodesk Green Building Studio tools, you can

• Capture early sustainable design analysis to support the process of reducing or eliminating negative environmental impacts.
• Communicate among the extended building design team using Autodesk design applications and other compatible energy and green analysis software.
• Gain a competitive advantage with increased client satisfaction and improved environmental performance.

Autodesk Green Build Studios Q&A (pdf - 52Kb) Autodesk’s acquisition of Green Building Studio’s assets was completed on May 1, 2008. They've completed the migration of the web service to Autodesk’s hardware. New users and existing Green Building Studio customers can now access the web service in the following manner.

• Current ‘pay-as-you-go’ customers can take advantage of a limited free trial period scheduled to conclude on or about June 30, 2008. Log into your existing account, accept the new Terms of Use agreement, and start realizing carbon neutral design with free analysis on up to two building projects per account.
• New customers can take advantage of a free 30-day trial period. Create a new user account, accept the Terms of Use agreement, and start realizing carbon neutral design with free analysis on up to two building projects per account.
• Returning annual subscription corporate customers can continue to use the Autodesk Green Building Studio web service as usual for the remaining term of your original subscription purchase. Just login to your existing account and accept the new Terms of Use agreement.
• To purchase single user annual subscriptions ($745) and 10-user corporate annual subscriptions ($4,995), login to the Autodesk Green Building Studio web service, accept the new Terms of Use agreement, and select the Upgrade link on the Project List page. Please note, PayPal TM payment services are no longer available. A note to Graphisoft users, the ArchiCAD add-on is temporarily unavailable while we are making updates to our new servers. We do expect availability soon and apologize for the inconvenience.

Users of Autodesk’s Revit®-based software applications who register for the Autodesk Green Building Studio service can now access the service directly with a plug-in available from our Downloads page after login. If you have questions about a new or existing account, please contact their technical support staff directly via email. Technical support can be reached at support@greenbuildingstudio.com.

The import gbXML (Green Building XML) feature will import data into a TRACE 700 project file based on building dimensional information exported from a CAD drawing. The CAD software must have the capability of generating a XML file that meets the Green Building XML requirements such as AutoCAD MEP.

The generated TRACE file will have the rooms defined (floors, walls, windows, etc). Note that users have the option of selecting what data to import from the CAD model into TRACE. The user will then need to define the template information for the file (internal load information, construction types and ventilation airflows) to refine the room inputs. After running the simulation, output information from the TRACE program can be exported back to the CAD model (space airflows, heat/cooling loads, etc.).

The gbXML standard is in the process of being accepted by most CAD vendors. Autodesk and Bentley will likely be the first two vendors to use this feature. The import has been implemented in TRACE for a few years now (leading the industry) and the export functionality is available in version 4.1.5 or greater.

C.D.S. has completed similar development with VariTrane Duct Designer. VDD can now import files using ddXML. Analysis can then be performed on the duct design and sizing/pressure detail information can be returned directly to the CAD model through an export feature in the program. For additional information on VariTrane Duct Designer or ddXML call the C.D.S. support center at 608-787-3926 or e-mail at: cdshelp@trane.com . For additional information specific to gbXML go to http://www.gbxml.org/ .

Exporting gbXML data from AutoCAD MEP

1. Open the drawing file in the AutoCAD MEP in this case.

Note: Verify that the latest version of AutoCAD MEP is installed before beginning this process. Autodesk products are updated with Live Update, which downloads patches to your product using Communication Center. Users can use Live Update to check for updates when a web connection is established. If a product patch is available, notification of its availability is received on the AutoCAD status bar, and the patch can be either downloaded directly from an Autodesk server or modified first before being copied to users' workstations.

2. Go to the File drop down menu and select Export to gbXML.

3. Select the location to export the gbXML data to, the number of zones to export, input the building type and zip code, then press the Start button to begin the export process.

4. When finished, press the Close button and exit out of AutoCAD MEP.

5. Using Windows Explorer, place the gbXML export file into the TRACE 700 Projects directory, typically this will be C:\CDS\TRACE700\Projects.

Importing gbXML data in TRACE 700

1. Open TRACE 700 and start a new file. This can be done by going to the File drop down menu, clicking on New, then TRACE 700, then entering a name for the file, and clicking on Open.

Note: Verify that the latest version of TRACE 700 is installed before beginning this process. Updates can be downloaded by going to the Help drop down menu, selecting Trane on the Web, and choosing Check for Updates or visiting the Download Center at http://www.tranecds.com/.

2. Go to the File drop down menu and select Import gbxml…

3. Navigate to the .xml file that was created during the export from AutoCAD MEP and click on Open.

Note: If errors occur during the import process please install the latest MSXML from Microsoft from http://support.microsoft.com/default.aspx?scid=fh;EN-US;sp

4. Select the desired information to import from the gbXML file and click OK.

5. Note any error messages that occur during the import process and click OK. Make sure to verify the inputs that relate to the error messages in TRACE input file. In this case, ventilation airflows were input in two ways in the CAD file, therefore one of the methods was selected to be used in the import.

7. Verify/refine the inputs in Create Rooms and/or use Templates to make changes in mass (see How to Use Templates.doc for details on how templates work).

Note: Due to the gbXML import, the vast majority of inputs for Create Rooms will have been filled out during the import process. Also, note that 75+ percent of the time that it takes to input a file is typically spent in Create Rooms and the gbXML import can reduce this time by more than two thirds.

8. Add additional details to the airside systems in Create Airside Systems.

Note: For details on how to model different airside systems, please refer to the TRACE 700 Modeling Guide.

9. Reassign the rooms to the refined systems in Assign Rooms to Systems (see the document Zoning in TRACE.doc for details on how to zone rooms in TRACE). From this point on, the TRACE project file will function as a typical TRACE 700 file.

Note: For details on creating cooling and heating plants please refer to the TRACE 700 Modeling Guide.

Note: For details on inputting utility rate information see How to Create Utility Rates.doc.

Exporting gbXML data from TRACE 700

1. Open TRACE 700, open the project file (filename.trc), and calculate at least the design section.

2. Go to the file drop down menu and select Export gbxml…

3. Select the existing .xml file that was used during the import process

4. When the export is complete, the information for the rooms plus zones will have been exported to the xml file.

Importing gbXML data in AutoCAD MEP

1. Open AutoCAD MEP and open the drawing file.

2. Go to the File drop down menu and select Import from gbXML…

3. Select the xml file to import that data from and click on Open.

4. TRACE 700 calculation data should now be included with the drawing file.

GbXML Results Exported From TRACE 700

• Room
  • Space Loads - These loads can be found in the space loads section of the Room Checksums Report.
  • Cooling Skylite Solar
  • Cooling Skylite Conduction
  • Cooling Roof Conduction
  • Cooling Glass Solar
  • Cooling Glass Conduction
  • Cooling Wall Conduction
  • Cooling Partition
  • Cooling Exposed Floor
  • Cooling Infiltration
  • Cooling Lights
  • Cooling People
  • Cooling Miscellaneous Equipment
  • Cooling Ceiling
  • Cooling Ventilation
  • Cooling Over-sizing
  • Total Cooling
  • Heating Skylite Solar
  • Heating Skylite Conduction
  • Heating Roof Conduction
  • Heating Glass Solar
  • Heating Glass Conduction
  • Heating Wall Conduction
  • Heating Partition
  • Heating Exposed Floor
  • Heating Infiltration
  • Heating Lights
  • Heating People
  • Heating Miscellaneous Equipment
  • Heating Ceiling
  • Heating Ventilation
  • Heating Over-sizing
  • Total Heating
  • Coil Loads – These values come from the System Component Selection Report.
  • Main Cooling Coil Tonnage (if main cooling coil is at the room level)
  • Auxiliary Cooling Coil Tonnage (if auxiliary coil is present in system)
  • Main Heating Coil Mbh (if main coil is at the room level)
  • Preheat Coil Mbh (if preheat coil is at the room level)
  • Reheat Coil Mbh (if reheat coil is at the room level)
  • Humidification Coil Mbh (if humidification coil is present in system)
  • Auxiliary Heating Coil Mbh ( if auxiliary coil is present in system)
  • Fan Airflow – These values come from the System Component Selection Report
  • Primary Fan (if fan is at the room level)
  • Auxiliary Fan (if system required)
  • Room Exhaust Fan (user specified)
  • Diffuser

Additional questions regarding TRACE 700, gbXML, Varitrane Duct Designer, and/or ddXML should be directed to the C.D.S. Support Center - cdshelp@trane.com or 608-787-3926.

Integrated Environmental Solutions (IES) launched VE-Ware sustainable design software that provides limited access to the company's Virtual Environment Apache thermal analysis software for free.VE-Ware reportedly gives instant feedback on a building's energy consumption and carbon dioxide emissions based on real geometry and using international data on climatic conditions and the typical characteristics of different building, room, and system types. Because it facilitates iterative design, allowing the comparison of different design, layout, and system options, VE-Ware is appropriate for use at early stages of design.In the United States, as a direct response to the Architecture 2030 Challenge, VE-Ware will assess how the building is performing against this benchmark, for example, whether it meets the current Architecture 2030 50% energy reduction targets.The data entry and outputs are managed for the user so that anyone can use VE-Ware to help reduce the energy consumption and carbon emissions of a building, the company states. For example, an architect, facilities manager, or building owner can undertake detailed energy and carbon assessments that can make a real difference to the green credentials of the building.Currently only models exported directly from Autodesk Revit can be accepted by VE-Ware. However, over the coming months the company plans to expand the software's capabilities to include other options for inputting the geometry data. The goal is to make VE-Ware available globally to anyone who wishes to use it, regardless of vendor or system.The free VE-Ware will be released in June 2008. However, interested parties can register now at the IES Web site.

Autodesk also announced that it has acquired certain assets of Carmel Software, which include their Design-Build, Duct Size, Estimate, Loadsoft, Refrigeration, Residential, and Green Toolbox products. These tools will support Autodesk’s vision for building information modeling (BIM) and strengthen Autodesk’s expanding portfolio of sustainable design solutions.Carmel Software has been developing and selling HVAC mechanical engineering software since 1995. Carmel's flagship product delivers thermal load calculations that give engineers information to appropriately size a building's HVAC systems. In addition, Carmel's software portfolio includes programs for duct sizing, refrigeration, pipe sizing, estimating, and life-cycle cost analysis. These applications are connected with the Revit platform for BIM via gbXML. Autodesk is investigating various strategies for integrating Carmel Software expertise and technology into its AEC design solution portfolio. For a brief transition period, while integration plans are finalized, these products will not be available for purchase. It is anticipated that Carmel Software technology will be available from Autodesk in some format in the coming months. The plans for integrating Carmel Software’s technology into Autodesk’s product portfolio are being investigated at this time. They will be making further announcements in the near future as these plans are finalized. Autodesk anticipates making Carmel Software’s technology available to Autodesk customers through a variety of methods, including but not limited to integrating the technology into its existing solutions. Both of Carmel Software's HVAC load calculation software programs (Loadsoft 6.0 and Residential 5.0) work with the latest versions of AutoCad MEP 2008 and Revit MEP 2008. AutoCad MEP and Revit are software tools that provide integrated AutoCAD-based building systems design and analysis. A user can import into Loadsoft and Residential the building information from the AutoCad MEP or Revit drawing, including room dimensions, number of people and much more. Each zone and room in the AutoCad MEP/Revit MEP drawing becomes a system and room in Loadsoft or Residential. After the calculations are performed in the software, the total cooling and heating load results can be exported back to AutoCad MEP or Revit MEP.The benefits of this integration is that it eliminates the tedious process of manually inputting information for each room and system. . . a process that often takes many hours for large buildings. Another benefit is that all of the cooling and heating load results can be exported back to AutoCad MEP or Revit MEP to aid in duct and piping design.The Loadsoft and Residential software programs are able to communicate with AutoCad MEP and Revit MEP using the Green Building XML schema (gbXML). gbXML was developed to facilitate the transfer of building information stored in CAD building information models, enabling integrated interoperability between building design models and a wide variety of engineering analysis tools and models available today. See http://www.gbxml.org/ for more information.

Green Building Studio announced they have signed an agreement for Autodesk, Inc. to acquire their assets. Green Building Studio (GBS) web service will soon join the Autodesk product family. The GBS team will continue selling, training, and supporting architects as they use the GBS web service to design carbon neutral buildings today and in the future.“Autodesk is committed to providing technology that makes sustainable design easier and more efficient,” said Jay Bhatt, senior vice president, Autodesk AEC Solutions. “We look forward to adding the Green Building Studio technologies to the Autodesk portfolio and helping our customers more easily leverage the coordinated, reliable data created in the Revit® platform for building information modeling (BIM) to help predict performance and design buildings with reduced environmental impact.”After closing this deal, Autodesk also plans to continue support for the Green Building Studio web service, carbon neutral building design training, and to strengthen the web service’s integration with its BIM software. The gbXML schema will remain an open industry standard, and the GBS web service will continue to be available to any other BIM software.“We have partnered with Autodesk for many years, and commend their ongoing support for sustainability,” said John Kennedy, President & CTO, Green Building Studio. “We are eager to contribute our industry expertise in green buildings to drive mainstream adoption of sustainability and accelerate the AEC industry’s transition to carbon neutral buildings.”