As building scientists and façade designers, our team is concerned about the fire risk of materials that are still being used on many New Zealand buildings, in particular timber framing and battens. We have seen high profile events such as the Grenfell, Neo, the Torch, Abbco Tower and many others. More locally Te Papa Museum, caught fire during original construction prompting a change in materials on that project. While these fires all have different characteristics and circumstances, we feel any residual risk or undefined risk is an unacceptable design practice.
Timber in no way poses the same risk as aluminum composites, high pressure laminates or foamed plastics but we’d prefer to design mid-rise buildings no have low or no risk versus an unquantifiable one. As an example, the New Zealand International Convention Centre was a timber framed roof structure which quite obviously was a contributing factor in extinguishing the flames 5 days later.
We are aware, and commonly specify proven safe, effective and cost neutral ways to achieve this by selection the right mix of products and applying scientific evidence approach. We don’t think MBIE has got this one right and needs to make this right before more buildings are needlessly put at risk.
Why don’t we have the right safety regulations in New Zealand?
We were heading in the right direction and MBIE had proposed changes to take effect in June 2020 that would have expanded the types of testing that could be used, clarified the definition of external wall material, and further clarified that all materials in the wall needed to meet test requirements. However, the proposed change was then reversed in October 2020 and now propose that timber is exempt from testing for buildings up to 25metres. MBIE has cited concerns on the impact these changes would’ve had on the timber sector, as well as the need for more evidence before making any changes. Yes, you are not wrong in thinking that these reversed changes mean our current regulations are now even more relaxed.
Evidence-based science, that’s what we do!
National news picked up on our concern and challenged us (we are talking a <3hr turnaround time to get the test completed) to conduct a combustible cladding test to prove what the safety risks are in tall building cladding. Click here for BTS footage of the test.
This test proved that in <10mins the timber studs of this insulated wall would ignite. At the 20minute mark we stopped the test and the results speak for themselves.
Let’s break that down.
You are hosting a BBQ on your 8th floor apartment balcony. Your guests have arrived and it’s time to heat the barbie up. The average BBQ takes 10-15mins to heat up, during which time you enjoy a beverage and chat about the weather (because, what else would you chat about). What you didn’t notice is that the BBQ had a broken leg and tipped over starting a small fire on the balcony. When you get back to the BBQ to check on it, the fire has crept up the walls and is now building its way up vertically through the adjoining walls. Before you have even put your steak on the BBQ, the studs in the wall between your apartment and are alight, and by the time you are ready to flip your medium-rear the fire has completed overtaken the whole interior wall.
As we know fire spreads QUICK, and we also know that there can be very few exit points in apartments – of which if fire was trapping an exit, the exit options become narrower and narrower.
Would you feel safe in an eight-story apartment with combustible material on the outside, now you are aware of how quick this can happen? I would like to meet someone so brave as to say yes.
So, what kind of regulations do we need?
If we look to standards around the world, New Zealand is falling behind. We are different from other developed countries in that timber is used in façade assemblies for tall buildings, which means we can’t use a lot of the fire testing data that is conducted overseas. This is where we need to bridge the gap with evidence and testing to ensure New Zealanders are kept safe in their homes and workplaces.
We’re not opposed to timber, and in fact think it’s a great building material, but to suggest it’s exempt from testing or poses no threat is short sighted and ignorant. What we feel is required is a way to demonstrate the wall system, and the timber specifically, is suitably well protected from a potential fire on the exterior. This can be readily accomplished with many different fire rated products. What is confusing the market is that not all lining materials can provide this level of protection, thus the impetus for our testing.
What can you do if you are concerned about your current property?
The first thing to understand is that our concern relates to apartment dwellings, the spread of fire is at a higher risk, and exiting a mid-high-rise apartment is more difficult for occupants than a residential house – particularly if the fire is blocking an exit point.
- Renting an apartment – speak to your landlord or body corporate if you have concerns
- Buying an apartment – have a building report conducted and understand all the in’s and out’s of your new property
- Body Corporates – reduce or eliminate the risk of a fire starting by introducing or enforcing restriction on smoking, BBQ’s or storage of combustible materials on balconies. Also review cladding areas at the ground level to move combustible materials such as skips, cars, storage away from walls that may contain materials that could pose a risk. While this doesn’t remove the fuel source for fire, it can reduce the ignition source and the resultant risk.
You can find more information on our Resources section of our website.