EIFS Substrate Preparation & Surface Compatibility 3

Question 1

A contractor is preparing to install EIFS over an existing EIFS system. What is the FIRST step an inspector should verify was completed?

Accepted Answer

Assessment of existing EIFS condition and bond strength

Answer

New color selection matches existing

Answer

Application of a bonding primer

Answer

Installation of new mesh over old system

Question 2

Which chemical treatment is typically applied to concrete block to improve EIFS adhesive bonding?

Accepted Answer

Muriatic acid wash followed by neutralizing rinse

Answer

Silicone water repellent

Answer

Polyurethane sealer

Answer

Latex-based paint primer

Question 3

When evaluating a substrate for EIFS, what does the term 'laitance' refer to?

Accepted Answer

A weak surface layer of concrete caused by excess water migration during curing

Answer

A type of concrete reinforcement mesh

Answer

A waterproofing compound used before EIFS

Answer

The minimum compressive strength of concrete

Question 4

What is the purpose of back-wrapping mesh around penetrations and openings in an EIFS substrate?

Accepted Answer

To reinforce the substrate edges and prevent moisture intrusion at terminations

Answer

To decorate the opening edges

Answer

To increase the R-value at openings

Answer

To provide additional fastening points

Question 5

What substrate preparation is required when EIFS is to be installed over existing glazed brick or tile?

Accepted Answer

Mechanical scarification or application of a manufacturer-approved bonding agent

Answer

No preparation needed if surface is clean

Answer

Application of standard EIFS primer only

Answer

Installation of drainage mat over smooth surface

Question 6

At what ambient temperature should substrate preparation and EIFS application typically NOT proceed without special cold-weather measures?

Accepted Answer

Below 40°F (4°C)

Answer

Below 50°F (10°C)

Answer

Below 32°F (0°C)

Answer

Below 20°F (-7°C)

Question 7

Which of the following substrate configurations is ACCEPTABLE for a barrier EIFS installation?

Accepted Answer

Exterior gypsum sheathing with all joints and penetrations properly sealed

Answer

OSB with unsealed edges at horizontal joints

Answer

Plywood with existing mold growth cleaned with bleach

Answer

Fiber cement board with no primer applied