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Cautionary Tale - What's the difference between CoA and CCC?

Updated: Nov 2, 2022

We've noticed a growing trend with homeowners and builders not knowing when an engineer needs to be involved for CoA or CCC. Engaging an engineer too late can cause massive headaches in the future. If you aren't sure of the differences, read on and take advantage of our initial consult offer at the end!

What's the problem?

With money getting tight in the construction industry, we've noticed a couple of things that homeowners/builders are doing that might seem cheaper at first, but cost them in the long run:

  1. Builders (and homeowners) trying to cut corners in design and avoid using an engineer to correctly specify any structural elements.

  2. Or, homeowners are unaware of the construction process and requirements from the get-go, and only engage an engineer when it's too late.

It is certainly cheaper to avoid using an engineer at first. But the cost of needing to engage us at the end of your project once construction is completed is significantly higher than if you consulted with us in the planning stage!

Why does it cost more?

As mentioned in our previous cautionary tale, here: structural elements are usually hidden from view. If the engineer was not involved with design and construction it can be difficult to prove to the Building Consent Authority that the element was specified or installed correctly. This means it can be very costly to get Certificate of Acceptance (CoA), or Code Compliance Certificate (CCC).

What is the difference between CoA and CCC?

Before going onto our two examples, we need to clarify the difference between what CoA and CCC is. Both documents can be issued at the end of construction works by the building consent authority (BCA) , usually the council, but they both fulfil slightly different niches in the consent process. You can check out more detail by clicking the arrow next to each item

Code Compliance Certificate
Certificate of Acceptance
In short - CCC is used when a building consent has been given, CoA is used when no building consent has been given

Cautionary Tale One

Lets get on to the details of our first project. A property owner wanted to install a pre-fabricated unit on their land in Wellington. We were initially contacted and engaged by the project's contractor and so were not in direct contact with the property owner, which added a layer of communication difficulty. Our initial scope was to recommend the pile depth for the foundations of the pre-fabricated unit so that the homeowner could get building consent, and eventually CCC. This sort of project is generally quite straightforward, and we scheduled a site visit to complete a site soil investigation (SSI). The SSI would identify the soil profile on site, and therefore the pile depth required for the unit. What we were not informed about, was that the prefabricated unit had already been installed with timber piles. We only found this out when we went to the site to carry out the SSI. Because the unit had already been installed we could not access the ground underneath it to assess the soil profile, or even assess the pile depth as seen in the photos below.

With the unit already in place, and building consent obviously not been granted, our scope shifted from providing the pile depth, to helping the property owner get the documentation required to complete a CoA. As mentioned previously, a CoA is a more time-consuming process because we need to compare and verify that what has been built complies with the building code. We requested evidence of the installation, and crucially how deep the timber piles were installed. Unfortunately, the builder could not provide this information.

What was the result?

We informed the contractor and the homeowner that the unit would need to be lifted and the piles re-installed if the existing piles are inadequate. This project is still ongoing and we are working with the client to remedy the issue.

Cautionary Tale two

In our second story, a homeowner had engaged a builder to remove a wall and install a beam to replace it. Both the builder and homeowner were unaware that the construction works planned required building consent, and they carried out the works.

This is where we came in. Once the owner realised they would need a final sign-off from the council they contacted us to help them check whether the alterations complied with the Building Code. Our first step was to consult with the homeowner on the differences between CoA and CCC (they were unaware of the difference) and informed them that since they didn't have building consent we'd need to confirm a couple of things:

  1. That there was 'comparable' bracing

  2. The beam was strong enough considering the load path from the roof

The homeowner was unable to provide evidence of the bracing so our involvement was to calculate the bracing requirements, and whether the installed beam was adequate. On site we assessed the installed beam and the roof space. We calculated the load paths from the roof, and the strength of the beam installed. Fortunately, the beam did comply with the Building Code.

The bracing was another story. Because we couldn't verify the bracing was comparable, we let the homeowner know that to comply with the Building Code, they would need to re-line the walls, pretty much re-doing the work they had already done.

What do we learn from these stories?

  • Before starting any construction works, know whether you need Building Consent first:

  • If you are planning any building works on your home, you should understand all the stages of your project, and at what point to engage with professionals

  • If you engage an engineer, keep them as up-to-date as possible on any developments on your project. This improves cost and efficiency

  • Know the difference between CoA and CCC, and realise that for CoA you need to provide enough evidence for structural works

If you are at all worried or confused about the process, or want to avoid the issues outlined in these stories, give us a call today! We offer a free initial consultation in our offices where you can discuss your plans, and get advice on what your next steps are. If you'd like to organise a consult with us, give us a call, or contact us here:


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