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How do I create a formula to calculate the area of a roof with Revu's built-in measurement tools?

 

A number of users have asked if Revu's built-in measurement tools are able to calculate the area of a roof from a plan view. This calculation is important because it can greatly affect your estimates, the air circulation in a room, and more.

 

The User Defined Columns (also called custom columns) in Bluebeam's Markups tab have supported formulas since version 8.0 with simple math functions. However, Bluebeam PDF Revu 8.5.1 is now equipped with new math functions that make it possible for you to use more complex formulas that will come in handy when performing roof calculations. These new functions include sin, cos, tan, asin, acos, atan, sqrt, log and ln. The values of Pi and e are also supported.

 

Getting started

First, you need to know two specific values in order to calculate the area of a roof: (1) the area of the roof in plan view and (2) the angle of the roof pitch. These two values can be calculated to provide the actual roof area.

 

Two User Defined Columns need to be created. The first is for the roof angle and the second is a formula that calculates the area.

 

Create the User Defined Columns

  1. Open the PDF in Revu.

  2. Press Alt + L to display the Markups list.

  3. Click the Manage Columns button in the Markups list toolbar. The Manage Columns window will display.

  4. Click the User Defined tab.

  5. Click Add.

  6. Type Roof Angle for the Name.

  7. Select Number in the Type drop-down list.

  8. Click OK.

  9. Click Add.

  10. Type Roof Area for the Name.

  11. Select Formula in the Type drop-down list.

  12. Click Custom.

  13. Type or copy and paste the following formula into the Custom field:

    14. [Area] / cos([Roof Angle] * (pi / 180))

  14. Click OK and then click OK again to close the Manage Columns window.

 

Here's how the dialog should look when creating the Roof Area formula:

 

 

Here is the dialog you should see after both new columns are created:

 

 

Measure the Roof

  1. Press Alt + M to open the Measurements tab.

  2. Click the Angle button in the toolbar.

  3. Measure the angle of the roof in the elevation view.

  4. Click the Area button in the toolbar.

  5. Measure the area of the roof in the plan view. The Area value that is displayed is incorrect, and will not be the final area.

  6. Press Alt + L to open the Markups list.

  7. In the Markups list, double-click in the Roof Angle column of the Area measure.

  8. Type the roof angle from the Angle measure and press the enter key.

  9. The Roof Area column will update and display the calculated roof area.

 

PDF after the Angle and Area measures are created:

 

 

Double-click in the Roof Angle column:

 

 

Type the roof angle:

 

 

The Roof Area is calculated:

 

 

Optional

You may want to hide the display of the area value in the plan view to avoid confusion:

  1. Select the Area measure.

  2. Right-click on the Area measure, then click Properties.

  3. Clear the Show Caption check box.

 

Explanation of the formula

[Area] / cos([Roof Angle] * (pi / 180))

 

Area is the value of the Area measurement.

Roof Angle is the value in the User Defined Column that you created.

Cos is the math function cosine

Pi is 3.14