Cladding Rectification - My Experience (A year on)

I have been wanting to write an article about my experience of cladding rectification projects for a while. I don’t want to throw stones, because having been involved in many cladding audits, feasibility studies and rectification works, I know how hard they can be as projects. The lack of saved documents, the differences between the documents you do have and what was actually built on site, the different products used in different combinations, different building geometries, access issues etc.

So hopefully this is read in the manner that I wrote it – simply some of my experiences while involved in cladding rectification works across many buildings from low rise residential properties in the suburbs through healthcare buildings to high rise residential properties in the city. It is not a jab at any one part of our industry – we all need to raise the bar to stop this happening in some other area of our industry.

Can’t we just…

These are some of the questions I have been asked more than once at the start of projects:

?“Can’t we just add external sprinklers and leave the cladding”

With regards to external sprinklers and or Drenchers, I am not aware of any sprinklers or drenchers which are listed (tested for the specific application) for use with combustible facades in this manner.

Sprinklers require a ceiling to “collect” heat for activation and this is not suitable for this type of external and possibly windy conditions.

Drenchers require some other means of detection to activate – ignoring they are not tested for this application, the issue of how to detect an external or a cavity fire at all times day and night on all elevations comes to the fore.

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?“Can’t we just add sprinklers to the balcony and leave the cladding”

Not as a general sweeping statement (I find general sweeping statements are best avoided) but it may be possible for certain portions of specific buildings.

What about cladding fires that don't start on a balcony? They will still require some mitigation strategy.

Please listen to your consultants and their reasoning when they say this is not a viable solution in isolation in many instances.

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“Can’t we just encapsulate the cladding with a fibre cement board or other non-combustible board product”

How would this even work?

Is there a board manufacturer out there willing to say their board is suitable?

Lets assume there is.

In the real world, can we encapsulate all areas of the cladding? What about the rear face in the cavity?

Can we guarantee that the installation will be perfect with no gaps etc

Can we guarantee that the installation remains perfect for the life of the building? How do we guarantee the encapsulation will not be penetrated or damaged? Buildings move, wind and weather act upon the materials and their fixings.

We have EPS or Polyethylene both of which melt at elevated temperatures:

Can we guarantee the melting temperatures will not be reached if there is a fire adjacent to encapsulated EPS or ACP PE?

I don’t believe so.

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“Can’t we just paint the cladding with a “fireproof” paint…”

The same issues that apply to encapsulation also apply here even if there was a “fireproof” paint for this application

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The Hierarchy of Controls also needs consideration here.

In short, the below figure shows the most effective at the top working down through the levels to the least effective.

In combustible cladding terms:

• Elimination is removing the combustible cladding and other combustible elements and replacing them with non-combustible elements

• Substitution is replacing the cladding and other combustible elements with less combustible elements or maybe a mix of less combustible and non-combustible elements

• Engineering (often called engineering controls) is isolating people from the hazard – keep the combustible cladding as it is but do not occupy the building (not really an option)

• Administrative – I’m not sure how this would apply in a combustible cladding context – no one is allowed to smoke, cook or have electricity in buildings?

• Personal Protective Equipment – give everyone a backpack with a fire extinguisher, breathing apparatus and maybe a rope ladder?

As you can tell, the first two Controls are most applicable in my experience

?Scope is key?–

This is not typically an issue where fire engineers and consultants are engaged by the Owners Corporation directly as they expect that we will look at the whole building.

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If there is a combustible cladding rectification program in your state, the cladding which is in the scope of the state rectification program is important.

The cladding which may not be in the scope of the state rectification program is equally important.

I have seen Glass Reinforced Plastics (GRP), timber, composite timber, concrete/EPS mix panels (generically EPS-concrete – I don’t want to name manufacturers or products) all excluded from scope despite them being combustible and in/on the external walls. From a fire engineering point of view, this is not a recommended approach as we should be considering all combustible elements on the facades and not excluding some just because they are considered by some to be not as dangerous as others. Just because a combustible cladding has been excluded from a state rectification program funding, does not mean we can ignore it – it simply means the money for rectification needs to come from elsewhere (namely the Owners Corporation).

This raises issues because there have been many cases where the Owners Corporation have suddenly been hit for large fees to fix items which are outside of the scope of the cladding funding but which still need fixing. For example rotten timbers or rusted loadbearing columns. They cannot be left as they are but may not be covered by the cladding funding and suddenly the owners have to pay for the remediation of these items and they don’t have the benefit of time to make decisions because the walls of their building are opened up exposed to the elements.

I think the fact that the owners have to pay for any of this works for cladding or for other repairs which are clearly down to poor construction or poor original design is the biggest tragedy in all of this and worthy of its own article.

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?It takes a team not just a fire engineer…

While combustible cladding rectification is often thought of as a fire engineering issue, like most built environment projects, it requires a multi-disciplinary team.

The fire engineer can advise on suitability of proposed replacement products but only from a fire engineering compliance point of view. With experienced fire engineers and other design team members you will get assistance with buildability and constructability of proposals etc and this can be invaluable for the main contractor on site. There’s no point in having an ideal world solution which can’t be implemented in the real world on site.

The structural engineer needs to advise if the new material can be supported or if new structure is required.

The fa?ade consultant/architect advises on many aspects of the replacement product, how it will align with the building features (windows, etc), R-values etc…

The RBS while not a member of the design team is involved in checking compliance and issuing Building Permits etc…

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The main contractor is key –

I had a contractor with no proposed design or designers engaged and they had opened up walls of a building. It took months of work because of their approach and the surprises found in the walls. I imagine this was not a pleasant experience for the owner occupiers. Other main contractors have been proactive and forward thinking and an absolute pleasure to deal with even under immense time and cost pressures from all sides.

Many of these time and cost pressures in my opinion placed the performance of the rectification works at unnecessary risk and actually ran the risk of repeating some of the issues which placed us here as an industry in the first place.

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Cavity Barriers

I will start by saying that I haven’t seen a cavity barrier in the wild in Australia in a wall which has been opened up for cladding rectification. Let that sink in.

?We typically see two main types in the design or rectification stages:

1. Specific cavity barrier products which may be open or closed state.
2. Non-combustible packed material cavity barriers.

Both have their uses and it will be a team effort to select the most appropriate taking into account the fire requirements, moisture management, ease of installation etc…

My view (anecdotally shared by a number of people in the industry I have spoken to) is that the NCC is lacking in terms of cavity barrier requirements.

So in the absence of Australian guidance as to where they should be installed etc where do the design teams look to for guidance? Other Countries? Which ones?

Does inclusion of a cavity barrier in a system which has a CodeMark mean that the CodeMark is not met?

Building facades often have multiple wall types. Some buildings with combustible cladding also have wall types which use non-combustible cladding but still have cavities, may have combustible insulation or other elements in them.

Does the rectification works have to remove the non-combustible cladding to replace the combustible insulation? Who pays – is this on the Owners Corporations or funded by the state rectification program?

What if the non-combustible cladding wall types have no cavity barriers installed – do we need to open up the walls to install cavity barriers or not? So in a rectification we may have combustible cladding being removed and cavity barriers around openings (windows and doors) at fire compartment boundaries and floor slabs etc but totally absent behind the other wall types which are not being replaced. How does the absence of cavity barriers in these wall types affect the expected fire spread?

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?Mike Tyson once said "Everybody has a plan until they get punched in the mouth."

There are more eloquent ways of saying this but what a succinct statement.

In cladding rectification terms, this means that once you begin to open up external walls in earnest, the surprises you will find will mean your plan requires revision – and quickly since you have removed the weatherproofing protection to the fa?ade.

This is one reason I was surprised to read the following quote from NSW Building Commissioner David Chandler OAM?“There will be no performance solutions in our scheme”:

https://www.commercialrealestate.com.au/news/nsw-cladding-remediation-to-kick-off-this-year-1066825/

I should say that I am a big fan of what I have seen of the work undertaken by the NSW Building Commissioner. We need more of his type across the country as holding people accountable is the key to changing the industry in my opinion.

It’s just that the quote stands out (I guess this is the reason the quote was used as the headline for the piece) and makes Performance Solutions sound like a dirty term.

Obviously Performance Solutions aren’t and shouldn't be considered a dirty term since the ABCB have gone to great lengths over recent years to clarify that Deemed to Satisfy and a well-structured and documented Performance Solution are equally valid ways of demonstrating compliance with the Performance Requirements of the NCC.

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How then will the following issues be dealt with as they are inevitable based on my experience with cladding rectification works.

I’m not saying that all of these should be immediately dealt with by a Performance Solution but the alternative options have pros and cons as does applying a Performance Solution:

1. Shortfalls in internal FRL provision?– We often found that internal plasterboard linings for example were not of the thickness necessary to provide the required FRLs. Internal linings can be upgraded or added to but the complexities and costs involved are huge. Often the recladding works are to be undertaken while owner/occupiers remain in their homes. If internal linings require upgrading then it is likely to require owner/occupiers to be temporarily relocated which adds stress, costs and time to the program. Would or should a state rectification program funding extend to this?
2. Internal lining penetrations?- We often found that internal linings were penetrated in ways which were not practicable to fire stop. By that I mean pipes, cables and other penetrations were often observed to require apartment access to have any chance of installing the fire stopping product correctly. Even with apartment access gained, there will often be tiling or cupboards and vanities in the way which would need removing for correct fire stopping installation and then re-instatement. If firestopping of penetrations is to be installed exactly as pre the requirements of a tested product/system then the works involved with removing tiling, cupboards and vanities is likely to require owner/occupiers to be temporarily relocated which adds stress, costs and time to the program. Would or should a state rectification program funding extend to this?
3. Lack of existing cavity barriers?– of the dozens of cladding rectification projects I have worked on, I am yet to see an existing cavity barrier installed onsite when we remove the combustible cladding. Given that there may be cladding which is not combustible on a building which is not being removed, it is clear then that there will not be cavity barriers behind this non-combustible cladding which is to be retained. This means that while cavity barriers can be installed behind any new replacement cladding, cavity barriers will not be installed across the full fa?ade as the non-combustible cladding which is retained will not typically have cavity barriers.
4. Existing combustible packers?– packers used for the levelling of windows etc are typically plastic and therefore combustible. NCC C1.9 lists some elements of external walls in type A and B construction which are exempt from having to be non-combustible. Packers for levelling window frames etc are not exempt. When they are discovered on site following removal of the combustible cladding, they therefore either require replacement, which is costly, difficult and likely to affect window levels and subsequently internal linings etc?or?they require a relatively simple Performance solution to justify why they may remain. With no Performance Solution option (as espoused for NSW) what cost, time and issues will be faced?
5. FP1.4?- While not a fire engineering item, NCC2019 A1 clause F1.0 notes that FP1.4 for external walls always requires a Performance Solution:

I could go on and on but I’m sure LinkedIn has a word limit.

In summary, there are lots of people trying to work together to resolve a problem which was decades in the making.

Its one thing to rectify the buildings and ban some products but if we don’t change the environment and mechanisms in the construction industry which allowed this to happen - it can and will happen again in a different area/discipline.