Dangerous defects with decks and verandas.

Decks and verandas with dangerous defects. Identified by Peter Weddell, owner/operator of Qld Home Buyers Inspection Service and Queensland Building Inspection Service, QBIS.

Dangerous defects with deck and veranda

Here are some examples of Queenslander style houses with veranda’s built using a similar method of construction to a deck that collapsed in recent years, at Ascot, a eastern suburb of Brisbane.


  • The floor joists are checked into the perimeter bearer and secured with nails. This will allow the supporting timber to separate and potentially collapse, under load.


  • Have an additional bearer fitted below junctions of the joists and bearer.

This would give far better long term support to the structure as it would not be reliant on brackets and securings that will rust and give way, eventually from exposure to the weather.

Defects with decks and verandas

A recently built veranda with the same method of construction, except for metal steel saddles fitted below the floor joists for support. Not a method of support that I would recommend. The joist saddles and nails will rust over time and lose support.

Important notes:

A far better method of construction would be to extend the floor joists over top of the bearer for full support, this is a method most commonly used.

The problem with this method would only be if more head clearance is required below the structure.

Dangerous defects with decks and verandas, signs to look for:

  • Post and/or columns for rot or rust to their bases.
  • Stairs and landings for rot
  • Flooring and structure for rot.
  • Railing securings and rotting of timber.
  • Bracing condition and securings (this is dependent on height of the structure).

Keep soil away from any timber to avoid rot and possible termite access points. Soil must also be clear of any steel supports to avoid rust occuring.

Some useful tips:

  • Consider constructing a roof above a deck, if it is exposed. This will not only give it protection but makes a deck more likely to be used in differing weather conditions.
  • Veranda’s & decks must be periodically checked and maintained.
  • Railing securings must be checked on a regular basis and be resecured when necessary.
  • Avoid using softwood in construction of decks, veranda’s, stairs and railings.
  • Bear in mind that softwood (treated and untreated) will rot sooner than treated hardwood.

Related information that may assist you.

Qld Government on decks & safety

Qld Government on planning and building a deck

QBCC Deck inspection guide

For independent Building Inspections Brisbane in all suburbs, Qld Home Buyers Inspection Service. qbis.com.au