By Greg Allan, tradesman and creator of Data First Coaching
Does a waterproofer need a licence in New Zealand?
A waterproofer working on wet areas, balconies or decks in a residential building is very often doing restricted building work, which means a Licensed Building Practitioner must design and carry it out. This is not a general trade licence, it is tied to the specific job in front of the waterproofer.
According to Building Performance, waterproofing is named directly as part of restricted building work, listing “Waterproofing - waterproof coating to solid walls and roofs exposed to airborne moisture - waterproof membranes to deck/balcony areas.” The LBP scheme overview explains there are seven licence classes administered under the scheme, and a waterproofer needs to check which class covers their membrane work.
This is not theoretical. The LBP notable decisions page records a case where the application of a waterproofing membrane, known in the trade as tanking, was held to be restricted building work. Being unlicensed is only an offence for work that is restricted, so a waterproofer doing a non-restricted repair sits outside this rule, but a basement tanking job or a balcony membrane very often does not.
What other registrations apply to a waterproofing business?
Aside from any licence tied to the actual membrane work, a waterproofing business still has to be registered as a business, covered for accidents, and run as a safe workplace. None of these are optional extras, they sit underneath every job regardless of licensing class.
Business.govt.nz says a sole trader does not need to register with a government agency at all, and only needs to inform Inland Revenue. A waterproofer trading through a company instead must register that company with the Companies Office, as explained on Business.govt.nz’s page on starting a company. As a sole trader, cover for injury comes automatically through ACC’s CoverPlus.
A waterproofing business is also a PCBU, a person conducting a business or undertaking, under health and safety law. WorkSafe New Zealand says a PCBU “must ensure, so far as is reasonably practicable, the health and safety of workers, and that other persons are not put at risk by its work.” Because so much waterproofing happens on balconies, roof decks and scaffolding, WorkSafe’s page on working at height also applies, and certain height work must be notified before it starts.
Why does holding the right registration not protect your margin?
Being properly licensed, registered and insured makes a waterproofer look solid on paper. It does not make the job profitable. Every certificate, flood test and warranty obligation that comes with doing restricted building work properly is a real cost, and if it is not costed into the quote, it gets absorbed quietly into overheads that never show up until the margin on that job has disappeared.
Think about what sits inside a single wet area or balcony job. There is the membrane itself, the cure time before tiling can start, the flood test to prove the membrane holds, and the certificate that backs the warranty the builder or homeowner is relying on. The industry Code of Practice for Internal Wet-area Membrane Systems says the Applicator and the Installer must be certified by the product supplier, and the Applicator should provide a Producer Statement, a PS3, to verify the installation complies. That certification, and the time spent producing the PS3, is real labour, not a formality.
If a quote shows healthy gross profit but the certificate, the flood test and a reserve for a possible remedial callback under warranty were never allocated to that specific job, the real number is smaller than it looks. Registration protects the waterproofer legally. Only honest costing protects the margin.
How do you cost compliance work into every quote?
You cost it the same way every time, as a line inside the job, not a guess folded into the overall price. That is the only way to see, job by job, whether the certificate, the flood test and the warranty reserve were actually recovered.
Picture a waterproofer quoting a run of bathroom and balcony jobs for the same builder, where the quoting process is slow and manual, and with so many parts on each job, from the membrane itself down to flashings, trims and fixings, it is easy for small materials to get left off a quote and then be missing on site. A quoting template with a checklist for each type of job, covering every material needed down to items like brackets and posts, closes that gap. The same discipline applies to certificates and flood tests: a defined method for pricing that compliance work into every quote, documented once rather than guessed at each time, means it is never left to memory.
What changes when AI agents take on this paperwork?
An AI agent is software that does a piece of office work the way you would do it yourself, using your prices, your wording and your rules. For a waterproofer, that means the agent can carry the non-billable side of compliance, chasing flood test records, building certificate paperwork, tracking warranty dates, without the office spending unpaid hours on it.
This is data first thinking: the real answer to whether compliance costs are being recovered sits in the waterproofer’s own job records and quotes, not in memory of how the last few jobs felt. AI agents can read that data week to week, flag the jobs where the certificate or flood test cost was not recovered, and keep the warranty reserve visible instead of buried. That frees the crew and the office to spend time on the next wet area, the next builder relationship, and the next flood test, rather than chasing paperwork that should already be sitting in the system.
This is general information, not legal, tax or employment advice. Check your own situation with the body named here or a qualified adviser.
Where can you check the current rules?
- Restricted building work, explains what counts as restricted building work and why waterproofing to wet areas and balconies is listed.
- LBP scheme overview, sets out the licence classes and who administers the scheme.
- LBP notable and significant decisions, shows how waterproofing membrane and tanking work has actually been assessed.
- General risk and workplace management, covers PCBU duties under health and safety law.
- Working at height in New Zealand, covers duties and notification for work at height, relevant to balconies and roof decks.
- Becoming a sole trader, covers sole trader registration and ACC cover.
- Starting a company, covers registering a company with the Companies Office.
- Code of Practice for Internal Wet-area Membrane Systems, covers applicator and installer certification and the Producer Statement (PS3).
How does Data First Coaching approach this?
Data First Coaching, built by Greg Allan, starts from the waterproofer’s own job and finance data through the Trade Business Intelligence, not from a description of the business. For this question, it looks first at whether the cost of certificates, flood tests and warranty reserves is actually showing up against each job, or quietly dragging the overall margin down without anyone seeing which jobs caused it. That is where the real problem usually starts, not in the registration itself.
The how, the method for costing compliance work and building the checklists and agents that carry it, is worked through inside the Academy, with members. The Academy is for waterproofers who are open minded, innovative and willing to share, because the Trade Business Intelligence is powered by every member, for every member.
