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*ARCHIVE* - BIA Update 40 - Safety reminder: Decks, balconies and balustrades 6 Oct 2004

The BIA again reminds owners of dwellings that balconies supported by untreated kiln-dried timber, particularly those situations where water pools rather than draining away harmlessly, pose a safety risk.

The reminder follows the Auckland City Council recently issuing a Notice to Rectify, advising the owners of a high-rise apartment building that balconies for 17 apartments were dangerous. The BIA understands these cantilevered balconies were constructed with untreated timber and may have been structurally weakened through the ingress of water and subsequent rotting of the timber framing.

Serious concerns about the safety of balconies, decking and balustrades emerged in the wake of the investigations into the weathertightness of houses in 2002.

The BIA issued public warnings twice and reminders have also been published in several BIA publications sent to territorial authorities and industry stakeholders. In light of this latest finding, the BIA reminds industry of this potential danger.

The BIA strongly recommends that territorial authorities, their advisors (e.g. builders, designers) and other professionals pay particular attention to this risk whenever they are on site. They should look for signs of potential problems in decks, balustrades and balconies that may be at risk of damage and rotting from water ingress.

Structures that pose a risk are those that rely on timber beams for support. Sometimes these beams are hidden behind cladding. Structures at most risk are on buildings with flat, lightweight claddings with plaster-type finishes, with balconies supported by untreated kiln-dried timber.

Risk factors

For balconies, consider these questions:

  • Has untreated kiln-dried timber been used for structural support of the floor or balustrade?
  • Is the building clad with lightweight materials with a plaster finish?
  • Does water puddle on the surface rather than drain away?
  • Are there any holes or cuts in the balcony floor surface or ballustrades?
  • Is it on a split-level or two or three storey house or a multi-storey apartment building?

Look at the balustrade:

  • Is it clad with lightweight material with a plaster finish?
  • Does it have a flat top where water sits?
  • Does it have a railing where water is able to leak down screw holes?

Warning signals

  • Balconies that move when walked on.
  • Damp spots or stains where the balcony joins the main part of the building.
  • Cracks, particularly near joints and corners.
  • Balustrades that wobble.
  • Balustrades where damp spots or stains can be seen on the cladding.

The BIA strongly recommends that, if warning signals are evident, advice should be sought from a qualified expert as soon as possible.

More information

BRANZ Advisory Helpline:
For those in the building and construction Industry: 0800 80 80 85
For the home owner and public enquiries: 0900 5 90 90
Institute of Building Surveyors: Ph 0800 113 400 or buildingsurveyor.co.nz

Or call your local city or district council for further advice.