EIFS Repair

EIFS Stucco with Drainage: A Comprehensive Guide to Modern Exterior Insulation and Finish Systems

EIFS Stucco with Drainage

EIFS (Exterior Insulation and Finish System) has evolved over the years, offering innovative solutions for modern construction. One such advancement is EIFS stucco with drainage, a system designed to prevent water damage and enhance the building’s longevity. This article delves into the details of this system, applied over an OSB substrate with a liquid moisture barrier, and compares it with other versions of EIFS.

EIFS Stucco with Drainage: An Overview

Liquid Moisture Barrier

The OSB substrate is coated with a liquid moisture barrier, including all window and door rough openings. This barrier ensures that no moisture penetrates the underlying structure, providing an extra layer of protection.

Starter Track

Positioned 4 inches above grade, the starter track is a crucial component. The first row of foam rests on this track, which features a drip edge to prevent water from cascading back to the wall. The weep holes in the starter track allow any trapped moisture to escape, making it an essential part of the drainage system.

Application Process

  1. Foam Application: The foam is applied with a basecoat, using a notch trowel to create natural vertical drainage channels.
  2. Basecoat with Mesh: A basecoat with embedded mesh is applied over the foam.
  3. Finish Coat: The final finish coat is applied over the basecoat, completing the system.

Comparing EIFS Systems

The Barrier System (Original Version)

The original EIFS, known as the Barrier System, lacked drainage features, leading to potential moisture problems.

EIFS with Drainage (Modern Version)

The modern EIFS with drainage, as described above, offers superior moisture management, protecting the structure from potential water damage.

Inferior Version: EIFS Drainage with Cloth Barrier and Mechanical Fasteners

This version, although providing drainage, lacks the efficiency and effectiveness of the modern system, making it a less desirable option.


EIFS stucco with drainage

EIFS stucco with drainage over an OSB substrate with a liquid moisture barrier represents a significant advancement in exterior insulation systems. Its well-designed components, including the starter track and moisture barrier, offer robust protection against moisture. By understanding the differences between this system and other versions, builders and homeowners can make informed decisions that best suit their needs.



Click to enlarge – Exterior Insulation and Finish System infographic

Frequently Asked Questions



What is the main advantage of EIFS stucco with drainage?

It provides superior moisture management, preventing potential water damage.

How does the starter track function?

It has a drip edge and weep holes to prevent water from cascading back to the wall and allow trapped moisture to escape.

How does the modern EIFS with drainage compare to the original Barrier System?

The modern system offers drainage features, unlike the original version, enhancing protection against moisture.

Industry Experience

With 30 years of experience in EIFS stucco repairs, I’ve witnessed the evolution of EIFS systems. The modern EIFS stucco with drainage represents a significant advancement, offering robust protection against moisture. Its well-designed components and application process make it a preferred choice for modern construction.

Learn More

Interested in learning more about EIFS stucco with drainage or other EIFS-related topics? Connect with me on Facebook or visit my YouTube channel for informative videos and insights.

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Projects Installing a Drainage System

EIFS Stucco drainage system being installed in Auburn Hills Michigan

We installed a drainage system on this store front when they had a major moisture problem. 

synthetic stucco drainage system installed on this store front in Canton Michigan

We removed the existing tile after they had moisture intrusion problems and replaced it with an EIFS stucco system with drainage. 

EIFS drainage vertical channels on a building repair in Northville Michigan

A car hit the corner of this building in Northville Michigan, and as usual I made sure to use my drainage system for the repair. You can see in this photo how the ribs of cement adhesive create natural vertical drainage channels.

Research on EIFS Stucco with Drainage

Understanding EIFS and Moisture Management

EIFS (Exterior Insulation and Finish Systems) has undergone significant evolution to address moisture management issues. Initially, EIFS relied on a barrier approach, which proved problematic in preventing water ingress due to reliance on perfect installation and materials. This method often led to moisture accumulation behind the system when elements like windows, caulking, or flashing failed, resulting in significant damage to the building structure (Buildingscience) (Forensic Engineering and Investigations).

The Importance of Drainage in EIFS

Research by the Building Science Corporation underscores the inherent flaws of the Barrier EIFS systems. These systems depend heavily on perfect workmanship and materials to keep water out. However, in real-world conditions, achieving and maintaining such perfection is virtually impossible. The study highlights that any breaches in the EIFS—such as cracks or poorly sealed joints—allow water to enter, which then becomes trapped behind the barrier, leading to potential mold growth, rot, and structural deterioration (Buildingscience) (Buildingscience).

Modern EIFS Solutions

To mitigate these issues, modern EIFS includes drainable or water-managed systems. These systems incorporate a drainage plane or cavity between the insulation and the substrate, allowing any infiltrating water to drain out effectively. This approach is designed to handle water that penetrates the outer layers of the EIFS, thereby protecting the underlying structure from moisture damage (Forensic Engineering and Investigations) (JLC Online).

Practical Implementation and Best Practices

Implementing a drainable EIFS involves several critical components:

  • Water-Resistive Barrier (WRB): A WRB, such as a building wrap or fluid-applied membrane, prevents water from reaching the exterior sheathing.
  • Drainage Plane: This can be created using grooved insulation, drainage mats, or other materials that provide a path for water to drain away from the wall.
  • Proper Flashing: Flashing at key points, such as windows, doors, and roof intersections, directs water out of the system.

These components ensure that any water entering the system is effectively managed and expelled, significantly reducing the risk of moisture-related issues (Buildingscience) (Buildingscience).


While the Barrier EIFS systems can function effectively as weather barriers, their reliance on perfect installation makes them vulnerable to failure. Introducing drainage systems within EIFS addresses this vulnerability by providing a reliable method for managing water intrusion, thereby enhancing the durability and performance of the cladding system in various climatic conditions.

For more detailed information, you can refer to the original research papers and technical guidelines provided by sources like Building Science Corporation and Envista Forensics. These resources offer in-depth insights into the design and implementation of effective EIFS drainage systems (Buildingscience) (Forensic Engineering and Investigations) (Buildingscience).

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