Gravity Cavity

Gravity Cavity™

Economical Rainscreen Drainage Plane

GC 1816, GC 1832

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Gravity Cavity
  • Gravity Cavity
  • Gravity Cavity
  • Gravity Cavity
  • Gravity Cavity
  • Gravity Cavity

Gravity Cavity Highlights

Gravity CavityTM rainscreen drainage plane (drainage mat) is the economy alternative to our Sure CavityTM drainage plane (drainage mat) product.  It works because it maintains a separation between the materials used for the veneer and the structural back-up wall to drain incidental moisture and dry out the building enclosure.  Gravity Cavity drains and dries better than mesh-based drainage matrix products because its 1/8” deep channels enable moisture that enters the building envelope to travel quickly straight down and out the bottom of the wall, and it won’t compress behind siding.

Features & Benefits

  • True channels conduct moisture to the bottom of walls faster than other rainscreen drainage mat products
  • High impact polystyrene ensures durability and prevents compression, waviness, and nail drive-through experienced with fiber-based mesh products
  • Saves installation time (half the time of furring strips and backer board)
  • 96% pre-consumer recycled content
  • The adhered fabric blocks mortar or stucco from filling the drainage channels and acts as a bug screen at the bottom

Protection from Incidental Moisture behind

  • Stucco
  • Thin Stone & Thin Brick
  • Fiber Cement & Cedar Siding
  • Brick
  • Natural Stone

Gravity Cavity Installation

  • Roll out Gravity Cavity™ rainscreen drainage plane/drainage mat over the WRB on the backup wall with spunbond fabric facing the weather. Back wrap 4’’ fabric on bottom course to act as bug screen.
  • Temporarily attach Gravity Cavity rainscreen drainage plane/drainage mat with hammer stapler on wood backup walls or dabs of adhesive on masonry. 
  • Roll out second and succeeding courses of Gravity Cavity™.  Overlap only the fabric.  Plastic butts directly to top of course beneath it.
  • Install veneer – attachment of veneer material will sandwich the Gravity Cavity™ drainage mat permanently in place in thin veneer applications. 

Gravity Cavity Ordering/Shipping

Contact MTI at 1-800-879-3348 for specific cost to your destination.

Gravity Cavity Specifications

GC1816 and GC1832 are 0.024"(0.6mm) thick, high impact polystyrene sheets. They are formed with corrugations and a spunbond polypropylene fabric on one side with a 4" (102mm) skirt on one edge.

Product Number GC 1816 GC 1832
Square Feet per Roll 100 200
Roll Length (Feet) 76 76
Roll Width (Inches) 15.75 31.5
Channel Depth 1/8" / 3.25mm 1/8" / 3.25mm
Rolls per Box 2 N/A
Boxes per Pallet 20 N/A
Rolls per Pallet 40 32
Square Feet per Pallet 4000 6400
Pallet Size 48" x 40" x 77" 50" x50" x 77"