When building a sloped roof, the substrate on which the roof is installed becomes very important; it is the foundation of a pristine roof finish and impacts the final exterior look of a home.

Viking SuperStrand is an H3.1 treated strand board designed specifically as a substrate for asphalt shingles to be installed on. It is used as the preferred substrate for Viking Roofspec's CertainTeed asphalt shingles and EcoStar tiles for a number of reasons, including its method of treatment, installation and physical properties.

SuperStrand is manufactured in Kaitaia by Japanese-owned Junken New Zealand. The mix of home-grown materials and labour – manufacturing to the standards of the Japanese – ensures the end product is of the highest quality. 

Juken's manufacturing process also ensures that every strand is H3.1 treated before the board is made, guaranteeing the treatment is distributed throughout the entire board (unlike mainstream treatment processes which involve spraying the outside). Full protection is maintained and cut edges or penetrations do not require further treatment or sealing.

SuperStrand is narrower in width than traditional plywood but a lot longer (800 x 3600mm). The narrower board makes it easier for installers to handle, carry and pass up through the trusses and onto the roof, saving on labour hours. The length spans an extra truss, resulting in a stronger substrate and less double-nailing at sheet edges – saving further time on labour. 

It is faster and easier to install as the square-edged profile of the board eliminates the need to align unforgiving tongue-and-groove joins. SuperStrand has no face grain and can be laid in any direction with a maximum span of 900mm, resulting in less wastage.

SuperStrand is also environmentally friendly. The azoles and permethrins, used to protect the board against fungal decay and insect attacks respectively, are water-based treatments – so no solvents are used. The preservatives used are organic biodegradable compounds.

The end product is a more rigid substrate. The extra length minimises the propensity for the board to sag between trusses, thus creating a flatter and more pristine roof. Most importantly, SuperStrand has the durability to match the extensive warranties (up to 50 years) that Viking Roofspec provides for its shingles and EcoStar tiles.