ARDEX UD 150 is also suitable for use with a range of substrate options and coverings, including porcelain, ceramic tiles and natural stone. Because the ARDEX UD 150 drainage mat doesn’t need to be bonded to the substrate, it’s an ideal option for those living in regions where councils will not approve the direct fixing of tiles. As Ronald Rose, Technical Services Manager at ARDEX New Zealand explains, the system is ideal for those looking for alternatives.
“Based on the NZBC E2/AS1 document for external decks, many councils have adopted the approach of not allowing tiles or any other coverings to be fully bonded to the waterproof membrane. The waterproofing needs to be accessible, which ARDEX UD 150 allows for.”
The requirement stems from past issues with waterproof decks. In many ways, a deck is similar to a low pitch roof surface. It collects water which, of course, must be drained. There are a few ways to protect the timber substrate of your deck. You can increase the fall, but while you’ll improve drainage, you’ll also end up with a deck that feels quite steep. Some people will add internal and external gutters, but these solutions can quickly become complex.
Then there’s tile jack systems, which offer ease of access and airflow, but come with their own set of issues. Not the least of which is the expensive and thick tile as well as the difficult and time consuming installation process.
Tiles on screw jacks are also less likely to lay flat, even when installed properly. Tile jack systems may also be louder to walk on and can even cheapen the look of a deck even though they may cost more than traditional tiled systems.