Enter the total length of the deck (ft) into the Deck Slope Calculator. The calculator will evaluate and display the Deck Slope. 

Deck Slope Formula

The following formula is used to calculate the Deck Slope. 

DS = DL * .25

  • Where DS is the Deck Slope (inches of slope height/drop)
  • DL is the total length of the deck (ft) 

How to Calculate Deck Slope?

The following example problems outline how to calculate Deck Slope.

Example Problem #1:

  1. First, determine the total length of the deck (ft). 
    • The total length of the deck (ft) is given as: 51.
  2. Finally, calculate the Deck Slope using the equation above: 

DS = DL * .25

The values given above are inserted into the equation below and the solution is calculated:

DS = 51 * .25 = 12.75 (inches of slope height/drop)


Example Problem #2: 

For this problem, the variables needed are provided below:

total length of the deck (ft) = 30

This example problem is a test of your knowledge on the subject. Use the calculator above to check your answer. 

DS = DL * .25 = ?