Stucco/EIFS Testing and Moisture Analysis

Exterior Insulation Finish Systems (EIFS) is a siding system used for exterior walls in both residential and commercial construction. One type of system which has been widely used on residential homes is called “Barrier” EIFS. Barrier EIFS typically is designed to resist water penetration at the outer surface but not water that gets behind it. There are some newer drainable EIFS systems on the market which are designed to allow the escape of such water.

As a homeowner with EIFS on the exterior of your home, you should perform frequent visual inspections to include:

1. Thorough checking of windows, flashing and sealant/caulk.
2. Damaged flashing should be repaired or replaced immediately.
3. Cracks or deteriorated sealants should be repaired or removed and replaced.
4. Periodic moisture testing would be prudent, especially for houses that were diagnosed with elevated moisture levels.


  • Many of the major relocation companies are refusing to “buy out” an employees house clad with EIFS without a complete invasive moisture survey.
  • Some insurance companies are refusing to insure an EIFS clad house without a moisture test.
  • An invasive moisture test and survey of EIFS is not part of a visual home inspection and many of the water intrusion problems would go undetected by a normal home inspection.
  • An EIFS inspection requires sophisticated meters and equipment costing several thousand dollars.
  • The industry estimates that 80%-90% of all homeowners, with EIFS or stucco exterior finishes, will experience some degree of moisture problems with their home.

Frequently Asked Questions

How is water entering behind EIFS?
Interfaces between EIFS and dissimilar materials are a common source of water intrusion, not the EIFS lamina (base coat and finish coat). The most frequent source of water intrusion is windows. Water frequently enters the EIFS at window locations in two ways: either through the joint around the perimeter of the window or through seams and joints in the window construction itself. Large quantities of water resulting in some of the most severe damage have frequently been discovered entering behind where a roof meets and terminates at the lower edge of a wall. Other potential sources of water intrusion are chimneys, decks and any other penetration of the EIFS lamina.

Why does water intrusion occur behind EIFS, and why is it important to discover it?
Water intrusion occurs through and/or around building components such as windows, doors, gable vents, penetrations, and a variety of flashing and construction details. Water intrusion also occurs when maintenance is ignored for these components and other critical areas, such as caulk joints. It is important to discover the occurrence of water intrusion, because water can enter behind the cladding and intrude into the unprotected sheathing, and in some cases, the wood structural members. Depending upon climate and the overall make-up of the wall assembly, the wall may not readily dry out. As water intrusion continues to occur undetected in a particular area, it can accrue to levels substantial enough to cause damage. Early detection of water intrusion is the key to minimizing and preventing such damage.

Is the location of water entry visible, and is the damage visible?
The location of water entry is often difficult to see, and the damage to the substrate and structural members behind the exterior wall cladding frequently cannot be detected by a visual inspection.

How serious are the problems if water intrusion occurs in EIFS-clad houses?
Damage can be significant if moisture intrusion goes undetected. Damage can become more serious if allowed to continue over time.

Should I have my EIFS home periodically checked for elevated moisture levels?
Testing should be done at least annually. A combination of two moisture meters should be used: (1) a non-invasive meter that scans through the wall without penetrating the EIFS lamina, and (2) a probe-type meter that penetrates the EIFS lamina and gives moisture readings of materials in contact with the probes. Only a professional experienced in EIFS water intrusion inspections should perform these tests.

What are the repair objectives?
The primary objective of repair is to eliminate water intrusion. Repairs should be made where elevated moisture is detected or structural integrity of the material is impaired. Where structural damage has occurred, those areas may require replacement of decayed wood products in addition to eliminating the source of water intrusion. It has been discovered that wet but undamaged substrate can dry out over time once the source of the water intrusion has been eliminated. Repair methods should address leaks associated with but not limited to:

  • Roofs – Install effective kick-out flashing at roof-to-wall intersections, diverter flashing around trapped valleys, and rake flashing.
  • Caulk Joints – Install effective caulk joints.
  • Windows and Doors – Caulk window jamb to sill joint and joints in any molding surrounding the window or door. Specially designed sill flashing is needed below most types of windows and most windows that are mulled together.
  • Decks – Install effective flashing.
  • Chimneys – Install effective cap flashing, cricket flashing at trapped valley, and effective kick-out flashing for roof-rake wall intersections.
  • Other Penetrations — Install effective caulk joint and/or flashing.
  • Cracks and Damaged EIFS Lamina – Repair according to manufacturer’s specifications.

Should the repair be monitored?
You should hire a professional experienced in EIFS water intrusion inspection to perform follow-up inspections within six months after the repair. Then once every year, the effectiveness of the repair should be monitored as part of the whole house moisture survey. If the repair is not successful, elevated moisture levels will be detected, and the repair method should be evaluated for the reason for failure. After making additional repairs, follow up with another inspection until such time that the moisture level becomes acceptable.

McKinney Home Inspections can perform an initial inspection of your home, determine if you have EIFS or conventional stucco and determine if the EIFS installation was performed correctly. If you wish to have an invasive moisture inspection, we will provide you a firm quote and schedule the moisture inspection.

Knowledge is power… If you have moisture problems, we must first identify the extent of the problem, and then you can make fact-based decisions regarding the next step in the repair process.

Call us today for your initial inspection.