Unit 101 is the one people skim, and it is full of marks. It is not about plumbing — it is about the industry you have just joined, the people you will be working alongside, and what the law says you are owed. Here is the whole thing in plain English.

The five key trades

Every building needs the same core group of people, and you are one of them. The five you have to know are the electrician, plumber, carpenter, bricklayer and plasterer.

Your own job covers more than most people outside the trade realise: hot and cold water supply, central heating, bathroom installation, and sanitation and drainage. The bricklayer does brick, stone and concrete block. The plasterer does plastering and dry lining. Simple, and it comes up.

Who runs the job

Key figures for the construction industry for level 1 plumbers
The examinable numbers from this article, in one place.

On anything bigger than a house, a group of people plan and run the work before a single pipe goes in. You will not meet all of them, but you are expected to know what each one does — and, more usefully, who to ask when something is wrong.

As an apprentice you will mostly deal with your own supervisor and the site manager. Knowing the rest is what stops you asking the wrong person and getting a wrong answer.

Main contractor and sub contractor

The main contractor holds the contract with the client and is responsible for the whole build. They rarely do every trade themselves, so they bring in sub contractors for the specialist work.

If you work for a plumbing firm on a new housing estate, your firm is almost certainly a sub contractor. That is normal, and it is the usual arrangement for plumbing on any large site.

Four ways a business can be owned

The four ways a construction business can be owned
The dividing line is whether you or the company carries the debts.

This is the bit people find dry, and it is worth two minutes because the difference between them is one idea: who pays if it all goes wrong.

Limited companies and plcs have to register with Companies House and file their accounts, which anyone can look up. Sole traders and partnerships do not.

The bodies, and how to keep them apart

Six organisations, and the exam likes asking which is which. There is a shortcut for each one.

The one people mix up is ECA and APHC. Both support contractors; the E tells you which trade.

What you are owed at work

These are rights in law, whether or not your employer mentions them.

You are entitled to a written statement of your main terms — the job, the pay, the hours, the holiday. There is a legal minimum hourly wage, with a separate apprentice rate. Your week is normally capped at 48 hours, averaged over 17 weeks; you can opt out of that in writing, but nobody can force you to.

Paid leave is 5.6 weeks a year for a full time worker — 28 days including bank holidays. Maternity leave runs up to 52 weeks; paternity is normally one or two.

Rights come with duties, and they are the obvious ones: turn up, do the work, follow reasonable instructions, work safely, look after the tools.

Discrimination

It is unlawful to discriminate on any of the nine protected characteristics named by the Equality Act 2010: age, disability, gender reassignment, marriage and civil partnership, pregnancy and maternity, race, religion or belief, sex, sexual orientation. Older material, some exam papers included, lists six of them.

Discrimination is not only refusing someone a job. It includes how people are treated day to day, and “banter” aimed at one person can be part of it. Worth being clear about: redundancy is the job ceasing to exist; dismissal is the person being let go, which needs fair grounds and a proper procedure.

If something is wrong and you do not know where you stand, two places: direct.gov for what the law says, and ACAS — the Advisory, Conciliation and Arbitration Service — for free independent advice and help sorting out a dispute without going to court.

Getting qualified, and getting on

To work as a qualified plumber you need three things: a CSCS card (Construction Safety Certificate Scheme), the relevant trade qualification — NVQ Level 2 for a plumber — and relevant on-site experience.

Note the difference: a plumber needs NVQ Level 2, an electrician NVQ Level 3. The usual route on from there is apprentice, qualified tradesperson, supervisor, manager, director.

🔢 The numbers worth memorising

48 hours
the normal maximum working week, averaged over 17 weeks
5.6 weeks
paid leave a year for a full time worker — 28 days including bank holidays
52 weeks
the maximum maternity leave; paternity is normally one or two weeks
9
the protected characteristics named by the Equality Act 2010
NVQ 2
the qualification a plumber needs — an electrician needs NVQ Level 3

⚠️ Where people go wrong

  • ECA or APHC? The E is for electrical. APHC is the plumbing and heating one.
  • Redundancy is not dismissal. Redundancy is the job disappearing. Dismissal is the person being let go, and needs fair grounds.
  • The clerk of works does not work for the builder. They work for the client, which is the entire point of the role.
  • “Limited” is about the owners, not the size. It means their personal money is protected if the company fails.
  • You cannot be made to opt out of the 48-hour week. You can choose to, in writing.

📝 8-Question Self-Test

Straight from the Level 1 course question bank. Click an option to see whether you got it right — the explanation appears instantly, and there is nothing to submit.

Your score: 0 / 8
Question 1 of 8
Which of these is one of the five key trades named in the standard?
Question 2 of 8
Which of these jobs belongs to the carpenter?
Question 3 of 8
Which trade is responsible for plastering and dry lining?
Question 4 of 8
How many key trades does the standard name?
Question 5 of 8
Which of these is a job a plumber does?
Question 6 of 8
Bathroom installation belongs to which trade?
Question 7 of 8
Lighting wiring and power supply wiring are the work of which trade?
Question 8 of 8
Hanging doors and installing windows are the work of which trade?

Going deeper: the same ground at Level 2

Level 1 gives you the shape of this. The Level 2 guides below take it considerably further — the regulations, the calculations and the detail you will need next. Free to read, same as these.