Beacon converts Revit element volume and material density to an embodied carbon value based on a user specified GWP coefficient. For results to be accurate it is essential that all elements have a volume and have the right material and density assigned.
Elements belonging to the following Revit Categories are considered:
- Structural Framing
- Structural Columns
- Structural Foundation
The total embodied carbon per square meter of floor area is measured against median values for various building typologies (Commercial, Residential, Education, Health Care, Lodging, Mixed, etc) and rated red, yellow, or green. Those median values are from data provided to the Carbon Leadership Forum since 2012 for the Embodied Carbon Benchmark Study. This tool will hopefully make embodied carbon part of an engineers design thought process and also allow them to share their data.
The EC takeoff is targeted for EC3 integration and SE 2050 metrics. Future development may include automated uploads to a central database and more detailed optimization strategies.
Beacon Phases and Levels Window
- Phases - Select all the phases in your Revit model to be considered.
- Levels - 'Unmapped Levels' column will display all levels existing in your Revit model. There is an option to restructure the levels.
- In the 'Build Map Level' column specify a Map Name (RETAIL in the example above).
- Transfer (>) all the levels that you'd like to place under this Map Name from the 'Unmapped Levels' column.
- When finished with one map level, transfer (>) it to the 'Mapped Levels' column
- If no Map Name is provided, the first level name from the list will be used (CELLAR-T/SLAB in the example above).
- Level mapping is an optional step, if no mappings are made, the Unmapped Levels will be brought to Beacon, and a mixture of Unmapped and Mapped Levels can also be used.
- Click OK when done.
Beacon By Category
The Beacon main window consists of three main columns. The left column is for Assigning GWP Values, the middle column is the Visualization Plot, and the right column is the Summary section.
Beacon groups Revit elements by Beacon Material Type, Revit Category, and Revit Material Name.
- The Beacon Material Type is derived from the Revit Material Class. For more accurate results, materials in Revit requires proper setup.
- Revit Material Class "Metal" = Beacon Steel
- Revit Material Class "Concrete" and "Masonry" = Beacon Concrete
- Revit Material Class "Wood" = Beacon Timber
- All other Revit Material Classes (Unsupported Revit Material Class) = Beacon Unknown
Revit Material Class
- Each Beacon Material Type is given a Tab (Steel, Concrete, and Timber), with 2 additional Tabs:
- The Unknown Tab contains all the elements with no material assigned, assigned a material with an Unsupported Revit Material Class, or was assigned a zero density material.
- The ability to calculate embodied carbon with the volume is provided, but concrete rebar will not be estimated via this route.
- It is generally better to fix the element material assignment in the Revit model so it no longer appears here.
- This will be the initial selected tab with all bold text if not empty.
- The Rebar Tab is used to estimate rebar embodied carbon from the concrete quantities. The Category-Material Name grouping is therefore identical to the Concrete Tab.
- The Quantity is by square feet for floors and cubic yards for everything else. A Multiplier is used to calculate the estimated rebar weight. That weight is then used to calculate the estimated rebar embodied carbon.
- Default Multipliers:
- Framing = 200 PCY
- Column = 150 PCY
- Wall = 250 PCY
- Foundation = 200 PCY
- Floor = 6 PSF
Rebar Embodied Carbon Estimation
- Each row in the table is a unique group of Revit Category and Material Name, for example, Framing-Steel ASTM A992 and Framing-Steel ASTM A500.
- The volume and density of each group is shown for quick verification.
- The volume can be increased/decreased with a Factor.
- Double-click a row to bring up a detail list of elements within that group for further verification. The ability to download the data to a CSV is available.
Detail Element List
- The GWP for each row can be assigned with current embodied coefficients via the GWP Type drop-down. A custom value can be entered directly into the GWP column. Use the Reset button to go back to the default assignments.
- The Concrete GWP Type drop-down is broken up by concrete strength and percentage fly ash and/or slag. For example, 6000-30-FA reads 6000 PSI concrete with 30% fly ash, 4000-40-SL reads 4000 PSI concrete with 40% slag, and 8000-00-FA/SL reads 8000 PSI concrete with 0% fly ash/slag.
The embodied Carbon can be visualized by Category (Framing, Column, Floor, Wall, and Foundation) or by Level. Each section is further broken down by Material (Total, Steel, Concrete, Rebar, Timber, and Unknown).
- Columns and Walls are split by level elevation and they will appear as multiple rows in the detail elements list.
- Hover over bars for actual values.
- Plots are zoomable, click on Category/Level button to reset to default.
Beacon by Level
- Select a Building Use from the drop-down (Commercial, Residential, Education, Health Care, Lodging, Mixed, etc) to compare your embodied carbon with the Embodied Carbon Benchmark Study from The Carbon Leadership Forum. The median value with Building Scope Structure and foundations was used as the benchmark.
- Red: Above +10% of median
- Yellow: Within +/-10% of median
- Green: Below -10% of median
- The total model embodied carbon per square meter of floor area is provided.
- Total Embodied Carbon Takeoff.
- Download all data as CSV.
- Material density is vital for Beacon. Make sure the assigned material has a physical density.
Assign Density in Material Browser
- For floors, walls, and foundations make sure the Type Structural Material is set accurately. It may require setting the right layer as the Structural Material in the Revit Edit Assembly dialog.
Edit Assembly to Select the Proper Structural Material
The standard Revit Floor family consisting of concrete and metal deck over estimates the concrete due to the concrete thickness being used to account for the entire volume. To remedy this overestimation of concrete, for any Floor assembly consisting of a Structural Deck with a non-zero density Material, Beacon will subtract from the volume half the depth of the Structural Deck, for example, in the images below the concrete volume will be calculated with 3.5" (5" - (3" / 2)), and it will use the deck profile properties to account for the metal deck embodied carbon. The actual deck weight will be calculated from the floor area and a deck psf. The deck psf is completely driven by the deck profile properties and deck material density.
Floor Assembly Structural Deck
Deck Properties Values
- The Unknown Tab is provided to catch elements with no material assigned, assigned a material with an Unsupported Revit Material Class, or was assigned a zero density material. It is generally best to make the necessary changes in Revit to have nothing under this tab.
- Primary Steel GWP values were taken from the Primary Structural Steel Frame Components EPD by the Metal Building Manufacturers Association.
- HSS Steel GWP values were taken from the Fabricated Hollow Structural Sections EPD by the AISC Steel Tube Institute.
- Concrete GWP values were taken from the NRMCA Member Industry-Wide EPD for Ready Mixed Concrete by the National Ready Mixed Concrete Association.
- Timber GWP values were taken from EPD's by the American Wood Council and Canadian Wood Council.
- Rebar GWP value was taken from an EPD by Gerdau Rebar, an authorized Concrete Reinforcing Steel Institute Fabricator Member.