Page 217 - Construction Waterproofing Handbook

3.104 CHAPTER THREE

FIGURE 3.101 Schematic detail for drainage requirements of EIFS system. (Courtesy of Parex)

Figure 3.109 provides a schematic view of proper transition detailing at a punch window.
Figure 3.110 details the transitioning at a typical mechanical penetration. Note that since the
penetration is round, the manufacturer has not terminated the flashing and weep system
above the duct. Water entering the EIFS cladding would travel around the duct and down to
where the flashing weeps the water back to the exterior. This makes the membrane flashing
applied around the duct critical to the watertightness of this detail, since water passing
through the EIFS system can bypass the sealant material and enter into the building if the
membrane flashing is not installed properly. Again an excellent waterproofing detail, but the
actual field application would likely result in upholding the 90%/1% principle.

Sealants
Expansion and control joints in EIFS claddings can be difficult to detail and waterproof
due to the thinness of the EIFS coatings. All EIFS manufacturers recommend that the
sealant be applied or adhered to the base coat only and not the topcoat. The topcoat of most