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Calcimator

Firestop Pillow Calculator

Calculate intumescent pillow count, layers, and cost from opening dimensions and void percentage.

Inputs

%

Results

Total pillows

10

Void area (sq in)173
Pillows per layer10
Layers needed1
Total weight (lbs)10
Estimated cost ($)$90.00
Staggered0
How to Use This Calculator
  1. Enter Opening width (in), Opening height (in), and Void percentage (%).
  2. Set Pillow size (1-3) and Wall thickness (in).
  3. Review the Total pillows result.
  4. Use Void area (sq in) and Pillows per layer to inform your decision.

How the result changes with Opening width (in)

Opening width (in)Total pillows
115
3514
6326
8735

What each input means

Opening width (in)
Width of the opening to firestop.
Opening height (in)
Height of the opening to firestop.
Void percentage (%)
Percentage of opening that is open void (not cables/pipes).
Pillow size (1-3)
1 = Small (2x4x9 in), 2 = Medium (3x6x9 in), 3 = Large (4x8x9 in).
Wall thickness (in)
Thickness of the fire-rated wall or floor.

What each result means

Void area (sq in)
Area of opening needing pillow fill.
Pillows per layer
Pillows needed for one layer across the void.
Layers needed
Pillow layers through the wall thickness.
Total pillows
Total intumescent pillows to order.
Total weight (lbs)
Combined weight of all pillows.
Estimated cost ($)
Material cost for pillows.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Opening width (in) = 24, Opening height (in) = 12, Void percentage (%) = 60, Pillow size (1-3) = 2 = 5 input(s) provided
  2. Calculate Total pillows
    Total pillows
    10 = 10
  3. Calculate Void area
    Void area = totalOpeningArea * voidPercentage / 100
    173 = 173
  4. Calculate Pillows per layer
    Pillows per layer
    10 = 10

Engine last updated .

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