Rainscreen Design Calculator

Cavity depth, drainage, and ventilation for rainscreen systems.

Wall area (sq ft)

Building height (ft)

Cavity depth (in)

Panel width (in)

Panel height (in)

Vent open area (%)

Design wind speed (mph)

Waste allowance (%)

Tab to move between fields

Panels to order

162

Design wind pressure (psf)

21.2

Vent open area (sq in)3,456

Cavity volume (cu ft)150

Cavity air changes/hr5.4

WRB/membrane area (sq ft)1,400

Furring channels (LF)277

How to Use This Calculator

Enter Wall Area in sq ft and Building Height in feet.
Set Cavity Depth in inches — 1.5 in is typical for most rainscreen systems.
Enter Panel Width and Panel Height, and Vent Open Area (%) split between top and bottom.
Set Design Wind Speed (mph) per ASCE 7 and Waste Allowance (%).
Review Panels to Order, Cavity Air Changes/hr, Design Wind Pressure (psf), WRB Area, and Furring Channels (LF).

How the result changes with Wall area (sq ft)

Wall area (sq ft): Total exterior wall area for the rainscreen system.
Building height (ft): Total height of the rainscreen facade.
Cavity depth (in): Air cavity depth behind the cladding panels (typical 1-2 in).
Panel width (in): Width of each rainscreen cladding panel.
Panel height (in): Height of each rainscreen cladding panel.
Vent open area (%): Percentage of facade area open for ventilation (top + bottom).
Design wind speed (mph): Basic design wind speed per ASCE 7 (3-second gust).
Waste allowance (%): Extra material for cuts and fitting.

Panels to order: Cladding panels including waste allowance.
Vent open area (sq in): Total ventilation opening area at top and bottom.
Cavity volume (cu ft): Total air cavity volume behind panels.
Cavity air changes/hr: Estimated air changes per hour from stack effect and wind.
Design wind pressure (psf): Component-level design wind pressure on panels.
WRB/membrane area (sq ft): Weather-resistive barrier area including laps and waste.
Furring channels (LF): Linear feet of vertical sub-girt/furring channels.

Identify Input Parameters
4 parameters
Wall area (sq ft) = 1200, Building height (ft) = 48, Cavity depth (in) = 1.5, Panel width (in) = 24 = 8 input(s) provided
Calculate Panels to order
Panels to order = ceil(netPanels * (1 + wastePct / 100))
162 = 162
Calculate Design wind pressure
Design wind pressure = qPsf * 1.2
21.2 = 21.2
Calculate Vent open area
Vent open area = ventAreaSqFt * 144
3456 = 3456
Calculate Cavity volume
Cavity volume = wallArea * (cavityDepth / 12)
150 = 150