PGDB Certifying Drainlaying Exam Refresher Course

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We’re here to make your drainlaying exams simpler, faster and way less stressful.

The Trade Lab® drainlaying exam refresher course prepares you to sit your PGDB Certifying Drainlaying Exam in easy-to-understand modules of easy-to-follow video lessons. We’ve bundled all the info you need into one place, so you don’t have to search through pages and pages of irrelevant content. 

Here's a sneak peek into the course


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Big benefits of the Trade Lab® course 

All PGDB information in one place 

When we Trade Lab® people sat our drainlaying certification exams, just sourcing the info we needed took ages. And that was before we could start revising. To save you that kind of pain, we’ve bundled all the content you need into one easy video course. 

Slam-dunk PGDB exam theory 

Like you, we loved our apprenticeship – because it was hands-on, outdoors and practical. But it didn’t prepare us to sit drainlaying certification exams. While the apprenticeship is an NZQA qualification, the exams are run by the PGDB – and they test the theory! Our exam refresher course makes the theory clear and easy to follow, so you can slam-dunk it on the day.

Tests, codes, standards and regulations … you’ve got this 

Everyone’s eyes glaze over hearing things like ‘net positive suction pressure’. It’s hard to remember all the different tests, codes, standards and regs. We’ve simplified things, and only include the parts you actually need to know. By the time you’ve done your revision with Trade Lab®, you’ll be all over this stuff.

Feel motivated and confident for the PGDB exams 

You know you’re a good tradie – and good enough to be a certifying drainlayer. But too many good people sit the exam and fail because they weren’t properly prepared. This is a waste of time and talent, not to mention moneymaking potential. That’s why we started Trade Lab® – to help drainlayers like you pass their certification exams, the first time. 

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One Time Payment

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$187 /month

Two Monthly Payments

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Why get your drainlayer’s certificate? 

When you get your drainlayer’s ticket, the sky’s the limit, and great things can happen.

· Become a certifying drainlayer

· Work on bigger projects

· Have more independence 

· Start your own business 

· Earn more money 

· Take on your own apprentices 

After passing his certifying and tradesman exams, Trade Lab® founder Nik McIntosh did a Bachelor of Construction, then landed a job at BECA running the largest hydraulic engineering team in New Zealand. He is also leaned on to provide advice on industry matters and opinions by the Plumbers, Gasfitters and Drainlayers Board (PGDB).

Your drainlayer’s certificate is the beginning of a rewarding and epic career.

Why Trade Lab®?


Learn from the experts

The purpose of the drainlaying registration exam is to assess your ability to ’design, specify, and install systems’. That’s what we do on a daily basis – nobody is better qualified to show you what you need to know and do to pass.

We will also help you avoid the three common mistakes most people make preparing for the PGDB exams by themselves: 

Most people don’t give it enough time 

The average successful candidate puts in 200 hours of study to prepare for the exam. It’s worth it.

Most people don’t do a refresher course 

The Trade Lab® refresher course is the best way to get all the info you need at the time you most need it.

Most people don’t get proper guidance 

We not only help you study for the exam, but we also give you tips and tactics for what to do (and not do) during the exam.

The team here at Trade Lab® hold some prestigious positions within the industry, and we actually practise what we preach. We use the same information you’ll be getting on this course ourselves, every day – designing buildings, specifying products, and providing advice to the PGDB.

I was put on to Trade Lab® by a friend. We shared the same problems: neither of us had sat an exam in years; we needed to study and refresh before the certifying drainage exam; and we were both busy at work and at home with young families. Being able to log in and cover a couple of topics each night made study very easy. I found the delivery suited me as it limited the amount of reading I needed to do after a busy day. It wasn’t until I sat the exam (and passed convincingly) that I realised just how relevant the study material had been. I recalled many of the questions being covered throughout the Trade Lab® course.

I would recommend these courses to all new and old preparing for an exam or as a very easy way to refresh your trade theory."

— Mark Dooley

What's in the certifying drainlaying exam refresher course?


We will provide you with a structured course to help you pass the PGDB Certifying Drainlaying Exam. You can access it wherever you are, whenever you want, on any device. 

Let’s take a look at what you will learn in each of the eight modules.

Module 1 – Overview 

Before we kick into the theory, we will take you through an overview of things such as how to use the website, how to study and sit exams, and how to navigate codes and standards. 

Module 2 – Legislation, Drainlaying Terminology, and Exam Calculations

We take you through the different legislation you need to know, including the Building Act and clauses of the NZBC and how they fit together, as well breaking down and explaining common exam calculations.

Module 3 – Pipework, Trenching and Design

In this module we break down drainlaying pipework requirements, trench separation and excavation requirements, and drainlaying design.

Module 4 – Drainage Components 

We take you through all things drainage, looking at the range of different components that build up a complete and compliant system.

Module 5 – Stormwater Systems

We take you through the stormwater pipe sizing procedure from start to finish, including soak pits, dewatering, and more.

Module 6 – Trade Waste and Onsite Wastewater Disposal

We look at a bunch of different trade waste management strategies and devices, how they work, and the situations they can be used in, as well as walking you through different onsite wastewater disposal systems, design requirements and how to size them.

Module 7 – Health and Safety

This module covers the Health and Safety at Work Act, WorkSafe NZ and Notifiable Works, and outlines the hazards we face as drainlayers and how to manage them safely.

Module 8 – Revision

The all-important revision module! We help you identify areas you need to improve on, how much effort to put into those improvements, and how to move forward quickly and efficiently. We also have great exam tips – what to do on the day and how to maximise your chances of success.

I would recommend Trade Lab® to anyone serious about passing their PGDB exams. Everything you need to know is included in the course content. And the ability to go over the modules as many times as needed is extremely helpful. Combine this with practising on past exam papers and you’ll be set for the big day."

— Robbo B.

Sign me up!


One Time Payment

Enrol now

$187 /month

Two Monthly Payments

Enrol now

Your instructor

Nik McIntosh - Founder

Hi there! I’m Nik McIntosh, owner and instructor here at Trade Lab®.

I am a certifying plumber and gasfitter and an associate director at Beca. I’m responsible for running the hydraulic engineering discipline across New Zealand and Australia.

I’ve been in the industry since 2005 and in the hydraulic engineering field since 2010. During this time I have also completed a Bachelor of Construction, graduating as a Senior Scholar in 2016.

I’m a firm believer that you and I, as participants in this industry, have the ability to impact its future for the better. And that collectively we can achieve this through collaboration, education, open conversation, and removing the barriers preventing people from getting the best information. I am incredibly passionate about this industry and its impact on the community around us. 

Who is this refresher for? 

Everyone who is sitting the PGDB Certifying Drainlaying Exam.

Who is this refresher NOT for? 

People sitting the PGDB Licensed Drainlaying Exam. 

Frequently Asked Questions

When does the course start and finish? 

The course starts when you purchase it and ends on the date of the next exam (e.g., if you purchase between January and May, you have access until the June exams). It is a completely self-paced online course, and you can drop back into any subject module as many times as you want, at any time during your studies. 

What if I am unhappy with the course? 

We would never want you to be unhappy! If you are unsatisfied for whatever reason, reach out to us in the first 14 days and we will give you a full refund. 

Can I find this information for free online? 

Not really – certainly not easily! We trawled for weeks through heaps of textbooks, official publications, standards docs and legislation so you don’t have to.


What format is the content delivered in? 

Mostly video, because it works best. You get video instruction and step-by-step walkthroughs of every major topic. There are some aspects that are text-based, with quizzes all the way through to make sure you’re on track.

Is my credit card secure? 

Credit card security is extremely important to us. We have partnered with Stripe to handle the billing and provide a secure socket layer, 128-bit encryption. So feel comfortable knowing your transaction is 100% completely protected from bad guys. 

Sign me up!


One Time Payment

Enrol now

$187 /month

Two Monthly Payments

Enrol now

Hear from more of our students


Get our FREE definitive guide to sitting your PGDB or EWRB exams

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