NPCA’s LEED Calculator

Overview

The LEED Calculator was developed by NPCA in order to simplify the paperwork requested for the completion of LEED Credits MR 4 and MR5.Currently the LEED Calculator’s Regional Materialsdata entered is only designed to work for the United States version of LEED, because Canada offers multiple possible options beyond the typical 500-mile radius.

Precast Products / LEED 2009 - New Construction
Credit Number / Credit Description / Max Points
MR Credit 4 / Materials and Resources
Recycled Content / 1-2
Credit Requirement
United States
Use materials with recycled content.
weight of material postconsumer content + weight of ½ preconsumer content = 10%(1 point)
weight of material postconsumer content + weight of ½ preconsumer content = 20%(2 points)
Canada
weight of material postconsumer content + weight of ½ preconsumer content = 7.5%(1 point)
weight of material postconsumer content + weight of ½ preconsumer content = 15%(2 points)
Precast Contribution
Precast concrete products may contain supplementary cementitious materials such as fly ash and blast furnace slag, which will add to the project’s recycled content goals. Precast concrete products may also contain rebar and welded wire mesh made from recycled steel.
Precast Products / LEED 2009 - New Construction
Credit Number / Credit Description / Max Points
MR Credit 5 / Materials and Resources
Regional Materials / 1-2
Credit Requirement
United States
Use materials or products that have been extracted, harvested and manufactured within 500 miles of the project site.10%(1 point)20% (2 points)
The calculation is based on the overall materials cost. Materials cost includes all expenses to deliver the material to the project site. Materials cost should account for all taxes and transportation costs incurred by the contractor but exclude any cost for labor and equipment once the material has been delivered to the site.
Canada
LEED in Canada allows for a choice in one of the three methods for obtaining regional materials credit :
  • Use a minimum of 10% of building materials or products for which at least 80% of the mass is extracted, processed and manufactured within 800km (500 miles) of the project site.
  • Use a minimum of 10% of building materials or products for which at least 80% of the mass is extracted, processed and manufactured within 2,400km (1,500 miles) of the project site, and shipped by rail or water.
  • Use a minimum of 10% of building materials or products that reflect a combination of the above extraction, processing, manufacturing and shipping criteria (e.g. 5% within 800km (500 miles) and 5% shipped by rail within 2,400km (1,500 miles).
Credit 5.1 is worth 1 point for 10%.
Credit 5.2 is worth 1 point in addition to 5.1 for obtaining 20%
Precast Contribution
Because concrete uses plentiful and natural raw materials, concrete components can be extracted, harvested and manufactured within 500 miles of the project site.

Directions and Requirements

  1. Download the Recycled Content Request form from NPCA for distribution to producers of each component of your concrete.This Microsoft word document can be easily modified and saved for future use.Directions on how to add logos and modify the table can be found on the second page of the file. Distribute these to the producers of your precast component and keep these records on file, because the LEED AP (accredited professional) will be asking for copies to upload to Green Building Certification Institute.

You will need the following information documented in writing:

  1. CementPre Consumer content and Harvest location Zip Code.
  2. Coarse AggregatePost Consumer content and Harvest Zip Code.
  3. Fine Aggregate Post Consumer content and Harvest Zip Code.
  4. RebarPre & Post Consumer content and Harvest Zip Code.
  5. Reinforcing WirePre & Post Consumer content and Harvest Zip Code.
  6. Any SCMsPre Consumer content and Harvest Zip Code.
  1. The goal is to have the overall weight of each component within the specific product.If you do not have the weight of each component, you must calculate it working from your mix design data and weights of your steel.Multiply your mix design component weights with your concrete yardage number for the specific weight of that component within the product.
  1. Insert the values on the LEED calculator located at
  • The first step is to register or log in.If you have never registered for the LEED calculator, you must do so because your NPCA member registration is separate from the LEED Calculator.
  • Upon login select New Form.
  • Enter the Project information.
  • Enter your company information.
  • Enter a Product Name and any ID numbers you may have.
  • Enter the product’s weight.This is the overall weight of the product delivered to the jobsite.Once this information has been entered, save the document and you are ready to edit the components.
  • Edit the Logo Information. The ideal size is 280x60. The ideal type is jpg. It will be converted automatically but may look better if this criteria is met before upload.

Components

  • Edit the Cement Component. You can edit the name and add the cement type or designation if you wish. Enter the weight of the cement used in the product.One way to determine theaccurate number is to multiply your mix design cement number by the product yardage.Using the information you gathered in writing from your cement supplier, enter the pre and post consumer information.
  • Enter the product’s Water Weight.One way to determine the accurate number is to multiply your water mix design by the concrete yardage.Although water recycling on site is a sustainable practice, the USGBC does not count this as recycled content in concrete.
  • Enter Aggregate Components. Unless you are using some recycled aggregate such as crushed concrete or recycled glass aggregate, leave the post consumer content at zero.
  • Enter Reinforcing components.Make sure you enter the pre and post recycled content based on the information you gathered from your steel supplier(s).Enter the weight of the steel. If you do not have the weight, you can use the Internet to find the weight per foot of your steel and do a simple math calculation.
  • Enter any SCM components such as fly ash or slag.
  • Enter any other components that you may have.Forexample: You supply a steel hatch for an underground utility product as part of the complete delivered assembly.
  1. The total weight in the box should match the total weight listed in the product information at the top of the calculator. Double check that all data has been entered correctly. If the weights do not match, a warning will appear.The overall product weight originally entered has no effect on the calculations – it is there simply to provide averification of your component weights.You can produce the pdf when the numbers are not matching, but please verify that each component weight is correctly entered when you receive the error.
  1. Your plant zip code must be within 500 miles of the project zip code entered.If the material contains components that were sourced from a place within 500 miles but the final assembly was farther away, the product cannot be counted toward the credit.(LEED 2009, page 380)
  1. Publish the PDF file, save it to your hard drive and proofread.
  1. Download the Recycled Content Response form for submission as a cover letter to the LEED AP.Modify the document as required or use it as a base for creating your own.
  1. Supply the LEED AP with the Response Letter and all pdf files of final analysis from the LEED Calculator that the LEED AP requested.You should also include a copy of all component-supplied documentation.

Please feel free to e-mail or call Claude Goguen, PE, LEED AP, Director of Technical Services at NPCA with any questions.

National Precast Concrete Association
1320 City Center Dr. Suite 200
Carmel, IN, 46032
(317) 571-9500 (phone)
(317) 571-0041 (fax)

LEED Calculator – Screen Shot

LEED Calculator – Sample PDF