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Common building faults Part 1

By John Dowling www.abis.com.au


A recent analysis of 3000 recently conducted building inspections revealed a pattern of common faults. As an investor, it would be prudent to ensure that your inspector looks for these more common faults in any property you are considering.


One in three homes had some form of incomplete construction.


In most cases, this was due to pergolas not having eaves, gutters and/or down pipes which connect to storm water drains. Where this occurs, the pergola may not have local government building approval.  In fact, three in ten homes had either pergolas, rooms built in under the house or new additions that were not likely to have had local government building approval

as they were not constructed to any recognized standard.


One in four homes displayed evidence of structural cracking and movement


Common causes of these problems were: poor slab construction on cut and fill sites; the prolonged drought conditions affecting ground moisture (particularly in areas with highly reactive soils); the absence of control joints in brickwork; tree roots and excessive

moisture adjacent to or under the house.  In some cases these homes showed cracking and movement of a severity that posed significant danger to the occupants.  Root systems of existing or recently removed shrubs and trees may also change moisture levels in the ground

which may in turn, contribute to structural cracking. 


Nine out of ten properties had trees or shrubs close enough to the house to cause problems.

Although small cracks in concrete may not be harmful in themselves, they may allow moisture penetration to reinforcement which could cause progressive corrosion, leading to structural problems. Retaining walls were often found to be overturning or cracking, indicating insufficient support or drainage.


In a small number of cases (one in twenty), sagging, bowing, cupping and distortion under load were found.  These included:


* Inadequately secured roof framing

* Sagging pitched roofs due to increased roof loading, corroded fixings or inadequate framing

* Deflected slabs due to substandard workmanship, drying shrinkage or excessive loading

* Sagging timber floors due to under-designed floor framing, insufficient structural support inadequate fastening, poor workmanship, overloading or timber pest damage


One in three homes had significant conditions which could lead to structural damage


One in three cases had defective plumbing, roof plumbing or flashings as evidenced by nonexistent rainwater facilities, lack of general storm water drainage, faulty or decayed flashings, cracked or weathered roof cladding, decayed ridge capping, gutters and down pipes.


One in five homes had nonexistent or defective damp-proof courses bridged by earth, pats, flooring or additions.  Poor surface drainage around many properties was a significant problem.


One in twenty homes had been constructed either in un-tradesman like manner or using inappropriate or inferior materials.  Construction was unsatisfactory, sometimes to the point of being dangerous with flimsy handrails, unstable stairways, omission of structural members,

excessive notching of structural timbers, insufficient support by over-spanned framing or using under-strength timber.  In some instances there was a lack of adequate subfloor ventilation allowing for natural air movement below suspended timber floors to protect against degradation of timber caused by fungal decay and timber pest attack.


One in eight homes had evidence of surface breakdown or corrosion and loss of thickness to metal joists, beams and handrails.  This may eventually lead to structural damage.


A proper inspection of any investment property you are considering will identify any of the above conditions and consequently, protect you from unexpected and costly repairs at a later date.


In part 2 we will review the findings on timber pest damage and secondary and finishing elements.