EDUCATION > Did You Know? > Walls > Drained Back Ventilated or Vented (DB/V) Wall Systems

Drained Back Ventilated or Vented (DB/V) Wall Systems

drained-back-ventilated-rainscreen-system-th.jpgDrained back ventilated or vented (DB/V) wall systems consist of the following design principles:
  1. Exterior cladding
  2. Air space
  3. Insulation
  4. Air barrier
  5. Building structure
1. Exterior cladding in a DB/V wall system
  • Manages/controls water infiltration
  • May not prevent water infiltration
  • Wind and environmental load resistance
  • UV protection
2. Air space in a DB/V wall system
  • Ventilation cavity
  • Air flow
  • Drainage plane
3. Insulation in a DB/V wall system
  • Reduces heat flow into and out of building
  • Water resistant materials
  • Minimizes chances of condensation and thermal bridging
4. Air barrier in a DB/V wall system
  • Air and water resistive barrier
  • Designed/placed for proper climate zone
  • Last and most critical line of defense against water infiltration
  • Minimize condensation through vapor transmission
    • Note: air and water control are two separate entities. Vapor transmission/permeability values can vary upon air barrier selection
5. Building structure in a DB/V wall system
  • Structural building element
  • Brick or block wall assembly
  • Wood or metal framing
  • May incorporate an exterior facing such as plywood or exterior gypsum board
  • Ventilated wall
    • One which has a vent opening at the top and bottom of the air cavity, to promote air circulation
  • Vented wall
    • One which has vent openings only at the bottom of the air cavity, to provide drainage and minimal volume of air circulation
ATAS Products Utilized in DB/V Systems
  • • All profiles
  • • Hat and U channels
  • • Continuous Insulation (CI) channels
  • • Exposed fastened panels
  • • Such as PenumWall and Grand C