Texture-coated fibre-cement – horizontal cracking

Some homes built with texture-coated fibre-cement claddings around the mid 1990s to the mid/late 2000s have had problems with leaks. This applies particularly to those with waterproof decks and parapets, no movement control joints, no eaves and complex designs. Engaging a registered building surveyor with experience in leaky homes is strongly recommended where a leak is suspected. DIY repairs and repairs by non-specialist builders often do not solve the problem and may result in further problems. See our Weathertight guide for more details.

Texture-coated fibre-cement claddings are typically proprietary systems. Where a problem such as cracking is found, contact the applicator/supplier for advice.

Causes

Horizontal movement control joints not included

Framing timber movement

Moisture entry into building structure

Building subjected to vibration movement such as earthquake, high wind

Common

Cause

Horizontal movement control joints not included

Repair

  • where there is no consequential damage identified by the building surveyor as a result of the cracking, have a professional installer cut a horizontal joint and fill it with sealant. A shaped hard-coated polystyrene moulding or timber facing can be installed over the joint to protect the sealant. The trim should be fitted over a sealant bead along the top edge. The top edge of all horizontal timber facings should have a minimum 15 degree slope to facilitate water runoff. (Where possible, there may be benefits in horizontal joints being flashed in a similar way to the inter-storey junction flashing shown in E2/AS1)

  • if evidence of leaking through the cladding cracks is found, engage a licensed builder who has experience in weathertight remediation work. A building consent will be required for repair work where the cladding has not met Building Code durability requirements

Cause

Framing timber movement

Repair

  • as above

Cause

Moisture entry into building structure

Repair

  • engage a licensed builder who has experience in weathertight remediation work. A building consent will be required for repair work where the cladding has not met Building Code durability requirements 

Cause

Building subjected to vibration movement such as earthquake, high wind

Repair

  • as for first repair