The team at Fireshield are known as specialists in passive fire products, namely intumescent coatings for structural steel and timber, and are well known for their technical expertise. After years of research and development of prefabricated fire rated timber, Fireshield have recently introduced a new prefabricated product to market; WoodSafe. Contrary to their intumescent coating lines, WoodSafe is not a coating at all. The best way to describe WoodSafe? Fire-rated timber that looks and ages just like untreated timber.

There are two WoodSafe product lines, one for internal surface linings (WoodSafe Interior) and one for external use or areas of high humidity (WoodSafe Exterior).

WoodSafe Interior

WoodSafe Interior is available in a number of timber species and allows architects to achieve a Group 1-S rating (the highest fire compliance required) in timber. Up until recently, the only option to achieve this rating on timber was to have a specialist applicator spray on intumescent coatings. This typically involves locking the building site down for several days to spray and cure the coatings. The timber is ordered from Fireshield and sent to be pressure impregnated with the fire-retardant. The treatment is absorbed deep into the fibres of the timber. The outcome is a fire treated timber that looks indistinguishable to the original. The timber, cut to the designer's specified profile as battens, fins, boards or plywood, is delivered directly to site to be installed by the chosen builder.

The advantages of prefabrication and no on-site coating provides cost and savings in labour. WoodSafe impregnated timbers provide many advantages:

• The fire retardant properties of the WoodSafe timber are durable for the lifetime of the timber and require no maintenance.
• Not being a coating means that chipping or wear will not interfere with the fire safety properties of the timber.
• The chemicals used in the treatment actually increase the life expectancy of the timber due to its non-hygroscopic properties.
• Stains and colours can be used on WoodSafe so design is never compromised.
• The timber is FSC sourced and the end-of-life disposal is the same as that for untreated timber.

WoodSafe Exterior

WoodSafe Exterior timber is ordered, prefabricated and treated in the same manner as WoodSafe Interior, delivered to the contractor on site for direct installation. The advantage is WoodSafe Exterior can be used externally as it has been tested and certified as a Type A cladding, the only timber cladding in New Zealand with this certification. (Type A: fire rating required for cladding on buildings over 10m high or less than 1m from the boundary).

Currently this is available in Cedar only in Hermpac rusticated weatherboard profiles with more species being added in the future. There is no product comparison to offer here as clear intumescent coatings are unable to be used externally. The builder must follow the technical data sheet to install the WoodSafe as a cladding system with installation being no more or less arduous than installing any other timber cladding.

The process increases the life expectancy of the timber and the fire rating is durable for the life of that timber, never needing to be reapplied. WoodSafe Exterior has been used in projects throughout Europe and America for over 30 years. With Fireshield’s technical support, designers across NZ are once again able to create beautiful timber facades and facade features on buildings over 10m high.