90 Devonport

Eight storeys, ten thousand square metres, and a superstructure made almost entirely of wood. Every beam, column and floor slab at 90 Devonport is laminated timber — LVL, CLT and glulam — which makes it the largest mass timber office building in New Zealand.

Ultrafire installed the fire alarm and fire sprinkler systems, and maintains and certifies them on the ongoing cycle.

Why the structure changes the job

In a concrete and steel building, the structure is not fuel. In a mass timber building it is, and that reorders the whole fire safety case.

Timber behaves predictably in a fire — it chars at a known rate and the char layer insulates the sound wood behind it, which is why engineered timber can be sized to hold its load for a specified period. But “predictably” is not “inertly”. The consequence for fire protection is that detection and suppression stop being one layer of protection among several and start carrying a much larger share of the argument. A sprinkler system in a building like this is not there to save the carpet.

That is worth knowing when a system in a building like this needs servicing, extending or certifying. The specification exists for reasons that were argued out at design stage, and a contractor who treats it as a generic office fit-out will erode it a fitting at a time.

Who owns what

The building is held and facilities-managed by LT McGuinness. Tauranga City Council is the tenant, and brought its administration staff together under one roof here for the first time since 2014.

That split matters more than it looks. Under section 108 of the Building Act the owner supplies the Building Warrant of Fitness — not the tenant, however large and however public-facing. A council occupying a building does not inherit the warrant duty by occupying it. How the warrant cycle works.