PlumbReviseThe names trip everyone up at first — Level 1/2/3, Diploma, NVQ, ACS, Gas Safe. Here is the plain-English map of how it all fits together and the routes in, whether you are leaving school or changing careers.
Most people climb these in order. Revision starts to count at Level 2.
A short introduction to basic skills and safety (sometimes called Access to Building Services). Good for deciding if the trade suits you, but on its own it does not qualify you to work — and there is little written theory to revise yet.
The core craft qualification: cold and hot water, sanitation, central heating, the science behind it and an introduction to gas. The first real written and online knowledge exams begin here — so this is where revision starts to count.
Covered free in our plumbing path · Premium unlocks the full bankAdvanced systems, fault-finding, more complex and commercial work, and environmental technologies like heat pumps. Level 3 with on-site NVQ evidence is what makes you a fully qualified plumber.
An NVQ is assessed on real jobs: you build a portfolio — usually photos and assessor visits — proving you can do the work for real. A Diploma is the college side; an apprenticeship combines both.
ACS assessments — CCN1, CENWAT, CKR1, HTR1, MET1, CPA1 — are not a Level 1/2/3. They are a separate competency: you reassess every five years (let it lapse beyond 12 months and you re-sit the full Initial), and you renew your Gas Safe Register registration annually — that registration is what lets you work on gas legally. New entrants usually reach ACS through a gas Managed Learning Programme plus a supervised portfolio; a plumbing background is common but not required. The ACS explained →
Unlike gas, general plumbing is not a licensed trade — anyone can call themselves a plumber. Your competence is your Level 2/3 NVQ, plus, if you want to self-certify work, a Competent Person scheme (WaterSafe/WIAPS for water, Part P for electrics, the G3 ticket for unvented hot water). See the field reference →
Intensive courses pack the theory into months, but you will still need real on-site experience and a portfolio before you work unsupervised. No course skips that part — be wary of anyone who says otherwise.
There is no single “right” way in — only the one that suits your time, money and stage.
Earn while you learn over a few years — the Plumbing & Domestic Heating Technician (Level 3), or the Gas Engineering Operative (Level 3) on the gas side. Competitive to get onto, but the route the trade respects most: you build the NVQ portfolio on the job and you are paid throughout.
The real routes inA full-time Level 2 (then Level 3) Diploma gives you the knowledge quickly. But a Diploma alone is the classroom side — you still need real on-site experience and an NVQ portfolio before you can work unsupervised.
Diploma vs NVQ, explainedIntensive courses pack the theory into months — handy if you are switching careers. Be realistic: you will still need site time and a portfolio, and gas means a Managed Learning Programme (MLP) plus a supervised gas portfolio. No course skips that part.
Are fast-track courses worth it?The bits the course adverts skip. We answer them straight in our in-depth guides.