Materials for moisture and mould resistance

When you're choosing the building materials for your new home or renovation, materials with moisture and mould resistance are essential for a healthy home.

Creating your dream bathroom can cost a fortune so the last thing you want to do is pull it all apart to find defects. And yet, building experts agree that one of the most common defects they're called upon to fix is water leakage through showers.

A wet area is any space that's supplied by water - that means bathrooms, laundries, kitchens and toilets. They're generally divided into two groups: areas like showers, which are most susceptible to water damage; and more general semi-wet areas like floors and walls that are next to baths, basins, toilets and laundry tubs.

The problem

Steve Peluso, from Master Menders, one of Victoria's largest building insurance rectifiers, says that a combination of poor workmanship and the wrong materials for the waterproofing and the linings are the main causes of bathroom defects.

In this video Steve Peluso explains the problem and recommends how to avoid it.

You can find out more about disaster-proofing and materials for moisture and mould resistance in this article.

Where there's moisture, there's mould

Research by Research Engineer Dr John Straube and colleagues* shows that "moderating variations in indoor relative humidity through the liberal use of hygroscopic and 'breathable' materials can virtually eliminate the potential for fungal growth."

"The speed with which a surface can absorb moisture is important for avoiding surface condensation and surface relative humidities required to support fungal growth. Materials with a combination of the properties of vapour permeability and high hygroscopicity allow that material to quickly moderate humidity variations by storing or releasing significant quantities of water vapour."

Dr Straube also says that: "The cement-bonded wood fibres that make up James Hardie product are quite resistant to long exposure to moisture for significant periods of time." James Hardie test results for water permeability, rain durability and warm water immersion support this.

*J F Straube, Research Engineer, Building Engineering Group, Civil Engineering Department, University of Waterloo, Waterloo, Ontario, Canada, and V Acahrya,
Vice-President, Durisol Building Systems, 'Indoor Air Quality, Healthy Buildings, and Breathing Walls', http://oikos.com/library/breathingwalls/index.html.