EIFS – sealant cracking/degradation at movement control joint

EIFS (Exterior Insulation and Finish Systems) are a type of wall cladding where polystyrene sheets typically have a plaster-based coating and paint finish. There is often a fiberglass-reinforced base coat and jointing system and textured polymer or acrylic finish coats.

The weathertight performance of EIFS claddings is very dependent on good quality detailing and installation, the jointing system including sealants remaining in good condition and coatings being well maintained.

Causes

UV exposure

Sealant not suitable for being painted

Too much movement for the grade of sealant

Sealant not installed over a backing rod or bond breaker tape

Sealant at the end of its serviceable life

Common

Listed under: Exterior, adhesives and sealants, finishes, paint, cladding, walls, moisture, leaks, exterior insulation and finish systems (EIFS)

Cause

UV exposure

Repair

  • EIFS claddings are mostly proprietary systems. Where joints are compromised through sealant damage or degradation, contact the original installer (if known) or another manufacturer-approved specialist applicator for advice

  • inappropriate DIY repairs may lead to further problems

  • government reports have found that EIFS systems installed from the mid-1990s to the mid-2000s have had a comparatively high rate of weathertightness failure on high-risk dwellings. (High risk dwellings include exposed sites, complex layouts with multiple wall and roof junctions, multiple levels, narrow or no soffits, membrane decks intersecting walls.) If you suspect there may be leaks through the cladding – more likely where the cladding was installed between the mid-1990s and the mid-2000s – engage an experienced New Zealand Institute of Building Surveyors (NZIBS) registered building surveyor to look at the building

  • once the cladding has been repaired, inspect it at least once a year and ensure that the coating and joints remain in good condition

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Cause

Sealant not suitable for being painted

Repair

  • see first repair above

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Cause

Too much movement for the grade of sealant

Repair

  • see first repair above

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Cause

Sealant not installed over a backing rod or bond breaker tape

Repair

  • see first repair above

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Cause

Sealant at the end of its serviceable life

Repair

  • see first repair above

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