Once you have uploaded your plans into STACK and have set your scale, we can begin the takeoff for the rectangular duct system. In this example, we will start with a 16x14 duct work.
Start by creating a new takeoff. Set the takeoff name to 16x14 DUCT 24 GA and set the measurement type to Linear.
Select + Add items and assemblies
Go to STACK assemblies and select the Square or Rectangular Duct - Galvanized - Linear assembly under the folder HVAC > Installers > Rectangular Ductwork. Scroll down to the bottom of the folder list to also select the Insulation for Square/Rectangular ductwork - Linear (typo in Assembly) under the folder HVAC > Installers.
Scroll to the bottom of the assembly list and select + Add 2 assemblies to attach the assemblies to the takeoff.
You will now be directed to the Assembly options screen for the Square or Rectangular Duct - Galvanized - Linear assembly. At the top of each assembly options screen are instructions on how to use them properly. Be sure to always read these instructions as they are critical to the estimating process.
Input the values into the corresponding variable fields. In our example, because we are dealing with a 16x14 duct, you will start by put 16 in the Height Of Duct In Inches field and 14 in the Width Of Duct In Inches field. Estimate what your crew’s production rate is, and input that rate into the Linear Feet of Duct Installed Per Hour (in this example, 55 Lin ft/hr).
Under Item Groups, click the drop down box to the right of the duct size you are using (in our example, it’s Choose Duct Size 14X or 15X), and select the size of the duct (14” x 16” Rectangular Duct, Galvanized). Scroll down to the drop down box to the right of Choose Strapping and select your strapping (1” Galvanized duct strapping (100’)). To the right of Install Labor, select the labor method you will be using (1 HVAC Installer + Tender).
Under Insulation for Square/Rectangular ductwork - Linear, the height and width of duct will remain the same (16in x 14in). Indicate how much waste you wish to account for in the Waste Factor field (3%), and estimate your crew’s production rate for the Sfof Insulation Installed Per Hour (125).
Under Item Groups, select the type of insulation you will be using. In our example, we will use Type 100 Insulation and select CertainTeed Type 100 1” (25mm) SoftTouch™ Duct Wrap R-3 (5’x100’). In the drop down to the right of the Labor to wrap ductwork, select HVAC insulation installer. Click Save to save the assembly options and to be directed back to the Items + Assemblies menu on your takeoff.
Scroll to the top of the the takeoff settings and click Start Measuring to be directed to the measurement settings. Per instructions at the beginning of the article, there should be label options of Floor and Metal Gauge. Under the Metal Gauge label, select the 24 Gauge option. Direct your mouse to the plan page and mark out your distances for the 16x14 ductwork.
To measure other ductwork, scroll to the bottom of your measurement settings and click Duplicate and Modify. You can change the name to the new ductwork measurement (in our example, 12x12), and click Create. The settings from the previous assembly will be seen. Make the necessary changes, and then click Save at the bottom of the screen. Select the 24 Gauge option under the Metal Gauge label, and mark out your distances for the 12x12 ductwork. Repeat these steps until you have measured all of the different types of ductwork in the project.
Once you have finished measuring, you can now view your data in the Reports section. Click on the last report, Item Cost By Takeoff Report.