You built this business from the tools up. A sale can raise questions about PGDB licence coverage, contracts, employees, customer concentration, equipment, working capital, and owner-held relationships.
This guide explains evidence buyers may examine and questions an owner can prepare. It does not provide a valuation or predict buyer behaviour.
How buyers assess plumbing and drainage businesses
Underlying demand, licensing requirements, customer contracts, approved-contractor status, employees, equipment, and local relationships may affect a buyer's assessment. They do not guarantee revenue, retention, or a valuation premium.
Separate council, commercial, infrastructure, maintenance, project, and residential work using contracts, margins, concentration, renewal and termination rights, tender status, owner dependence, and delivery requirements.
PGDB Licensing and What It Means for Your Sale
Licence and supervision dependencies should be mapped before a sale process.
PGDB registrations and practising licences are held by individuals. Confirm which work requires which class, supervision, certifying authority, or other condition, and how the transaction affects the employing entity and workforce.
A buyer may map which individuals hold relevant plumbing, gasfitting, and drainlaying authorities and what happens if they leave. If the owner holds a critical certifying or supervision role, address the operating and employment consequences with PGDB guidance and advisers.
Use the PGDB public register and internal records to confirm licence class, status, expiry, work scope, and key-person dependence. Do not alter employment terms merely to improve a sale file. Obtain employment advice on any retention or transition arrangement.
If you are the sole Responsible Person and you intend to exit fully, address this before you go to market, not during due diligence.
How Plumbing and Drainage Businesses Are Valued in NZ
Buyers commonly examine normalised earnings when assessing a plumbing or drainage business, but there is no dependable sector-wide multiple. Revenue quality, licence coverage, customer concentration, management depth, fleet condition, working capital, and deal terms all matter.
Documented recurring work can improve a buyer's confidence in future earnings, while dependence on residential callouts, owner-held relationships, or one major client may increase risk. The contract terms, margins, renewal rights, and customer concentration still need to be tested individually.
Fleet, CCTV inspection equipment, excavation equipment, and water-jetting assets may require separate analysis of ownership, finance, condition, maintenance, utilisation, safety, and replacement needs.
Prepare support for owner remuneration, aged debtors, customer terms, equipment ownership, related entities, working capital, and proposed adjustments. Their effect depends on the evidence and transaction.
How to present infrastructure demand
Use current Te Waihanga, council, customer, tender, and contract evidence to explain relevant infrastructure demand. A public project pipeline is not contracted revenue for the business. Distinguish addressable opportunities from awarded work, backlog, and signed contracts.
What the Right Buyer Looks Like: and How to Identify the Wrong One
Owners may encounter several buyer models, each with different intentions for ownership, integration, financing, and succession.
Some trade buyers pursue integration benefits such as shared systems, purchasing, branding, or management. Others preserve acquired businesses. Ask each buyer to state its intended operating model rather than assuming the outcome from the buyer category alone.
Private equity-backed buyers commonly invest through funds with defined investment periods, but hold periods and deal structures vary. Review any earn-out, rollover equity, governance rights, leverage, and eventual exit assumptions with independent advisers.
Permanent holding companies state that they acquire without a planned resale. Their brand, integration, management, and seller-transition practices vary. Assess the actual governance and transaction proposal.
PermaTech acquired Tubman Heating in 2024 under its stated permanent-ownership model. That transaction demonstrates its approach to that acquisition only and does not guarantee another seller's outcome.
When meeting any buyer, ask three questions: What is your hold period? What happens to our brand? And can you show me a business you have owned for more than ten years and introduce me to the management team still running it?
Preparing for Sale: Practical Checklist
Start early enough to verify licences, correct records, and test succession without relying on a fixed minimum period.
- Financials. Three years of clean, accountant-prepared financials with owner remuneration normalised.
- PGDB licence register. Document every licence held by every staff member: licence type, number, expiry date, and the work they are authorised to sign off. Know your gaps before a buyer finds them.
- Job management system. A documented system, Simpro, Fergus, or similar, shows a buyer the business can be operated without you.
- Recurring contracts. Every council agreement, school contract, Watercare relationship and maintenance agreement should be in writing with documented renewal terms.
- Fleet and equipment register. Current, maintained asset register with purchase dates, service histories and valuations.
- WorkSafe NZ compliance documentation. Trenching, confined spaces, excavation, your SSSP documents, toolbox meeting records, and incident registers should be current.
- Aged debtors. Reconcile ageing, collectability, disputes, credits, provisions, and completion treatment. No universal age threshold determines value.
If you have been nearly ready for several years, use the checklist above to identify the next controlled step. Current demand, buyer interest, and price are transaction-specific. Reliable records, licence coverage, management depth, and a clear succession plan improve your ability to assess options without relying on market slogans.
If you would like to have a direct, confidential conversation about what your business is worth and what a sale might look like, PermaTech talks to NZ trade business owners regularly. No brokers, no obligations, no pressure.