DA or DEFS

Direct Applied or Direct Exterior Finish System – (DA or DEFS)

 

This exterior finish system is designed to install directly onto substrates such as siliconized core gypsum sheathing (top image) or cement board (bottom image).

Siliconized core gypsum sheathing (such as DensGlass, GlasRoc or FiberRock) is an acceptable alternate for cement board in protected areas such as soffits, portico, etc.

Cement board (such as Durock, or Permabase) is required in all non protected areas.

 

Direct Applied or Direct Exterior Finish Systems include the following components:

  • Sealer. Be sure to check with system manufacturer.
  • Base Coat with 25-50% Portland cement mixture (Type I or Type I & II) applied over entire surface.
  • Fiberglass mesh at joints or over complete surface. Again, be sure to check with system manufacturer.
  • System accessories such as starter beads, corner beads, window trim, and drip edges.
  • Synthetic finish.

They also have these typical characteristics:

  • Generally high impact resistance.
  • Require control joint every 144 sq. feet maximum to reduce cracking of surface.
  • EPS aesthetic shapes may be incorporated with overlapping fiberglass mesh.
  • Variety of acrylic finishes from smooth to Spanish.

DA or DEFS is used in these special applications:

  • Protected areas such as soffits and canopies may use cement board or gypsum substrates as noted above.
  • Stairwells and balcony walls must use cement board substrates.
  • High impact, no additional insulation needed.

Caution: DA or DEFS typically does not bridge joints in cement board without cracking.

 

DA or DEFS

  1. System manufacturer approved substrate
  2. Basecoat
  3. Reinforcing mesh over joint or continuous
  4. Finish

Note:  Modern DA or DEFS

  1. Now most manufacturers require Mesh over the entire wall.
  2. If moisture sensitive substrates, then a WRB is required.