Hi Rita C,
Thank for the additional information.
To start with some technical background, all timber finishes in an external environment will deteriorate over time. The time taken to deteriorate will depend on a number of factors, primarily the exposure severity, construction detailing, timber suitability for the exposure, protective paints or treatment used (if any) and level of maintenance following completion. Responsibilities for getting these right fall with the architect, the builder and the owner, depending on at what point you are in the building life cycle.
The reason/s for the failure as you describe could be attributed to any of, or a combination of the above factors and responsibilities and really would need further investigation to narrow it down. It can become quite complex with many arguments and counter arguments. However, the severity of deterioration does suggest that the timber material was unsuitable for the weather exposure as one could expect the material not to be that critically dependant on the protecting coating, if any.
If the insurer is saying that it is a maintenance issue, the task is to demonstrate that the wrong material was used in construction and that this was the builder’s responsibility (and not that of the architect).
That said, pursuing a claim may involve time and money and this needs to be weighed up against the cost of replacing or repairing the material.
I am happy to give you an opinion (at no charge) on whether it is worth further pursuing a claim, but I would need to examine the documentation and the site to do this. I am contactable via our website at http://www.thorburnassociates.com.au .
Regards,
Rob T