Dec-K-ing Enjoys the Sea Views


The roof of an upmarket Mount Maunganui apartment serves as a wonderful viewing platform overlooking the Pacific Ocean from six floors up. But by early 2009, the apartment's tired butyl rubber membrane roof was beginning to oxidize - a condition more commonly known as "chalking-off".

Not only was this old butyl struggling with the intense UV, the membrane (being black) had a propensity to become extremely hot; putting undue pressure on the air conditioning requirements (and therefore energy costs) of the building.

Additionally, the messy, black butyl powder from this chalking-off was beginning to rub-off onto the apartment owners (and their guests) feet when they went onto the roof to enjoy the view.

The owners, The Body Corporate, had installed some artificial grass on top of the butyl to alleviate these issues. Despite marginal success, this was acknowledged as a bit of an "apologetic" strategy - certainly not in-keeping with the quality and location of the building.

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The head of The Body Corporate contacted a local Bay of Plenty Viking Membrane Approved Applicator for suggestions as to where she could find an attractive membrane system that was sufficiently durable to withstand New Zealand's tough climatic and UV conditions.

The applicator immediately proposed Viking Dec-K-ing and put her in touch with the Viking Roofspec Territory Manager. The Territory Manager explained that a Viking Dec-K-ing Membrane system not only possessed the above properties but was also:

  • BRANZ Appraised;
  • Heat-welded at its seams for maximum watertightness;
  • Possessing a propensity to heat-up a lot slower than other deck surfaces;
  • Embossed surface for maximum grip;
  • Mesh-reinforced for puncture resistance

...she knew her quest to find the ultimate decking waterproofing solution had come to an end.

The Viking Approved Applicator faced several challenges, the first one being the weather. Being winter time, Viking's Technical Specialist insisted that once the butyl rubber had been removed and disposed of, the porous concrete substrate would need to be coated with Aquaguard 101 to seal its surface. This would prevent the need for expensive down-time to dry out the substrate after each rainfall during the installation period.

But before they could apply the sealant, they faced the challenge of having to smooth the extremely rough texture of the concrete. If not dealt with prior to laying, this rough texture would show through the surface of the membrane.

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Once the substrate had been diamond-ground and then sealed with Aquaguard 101, the application team successfully installed approximately 500m2 of Viking Dec-K-ing (between periods of appalling weather).

The Body Corporate members were delighted with their wonderful new roof deck, which allowed them to entertain guests and view the ocean on a robust, but more importantly, watertight membrane; the aesthetics of which are in-keeping with the quality and location of the building.