Trainees often use “ACS gas portfolio” or “Gas Safe portfolio” to describe the supervised on-site evidence they build as part of their gas training route, before progressing to the relevant assessment. It is not a portfolio issued by Gas Safe Register, and the exact evidence you need depends on the programme you are completing.
What it comes down to is this: a written exam cannot show that you can actually do the job. The on-site evidence is the part that shows you have carried out real work, on real appliances, in real properties, under appropriate supervision.
The exact evidence you need depends on the requirements that apply to your programme and the paperwork issued through your training centre.
What goes in a gas portfolio
The exact contents are set by your training centre, but the shape is consistent. A portfolio is built from evidence of you doing the work:
- Photographs of you carrying out each task — clear enough that an assessor can see what is being done and that it is you doing it
- Details of the job: what the appliance was, what the work involved, where and when
- Confirmation from the Gas Safe registered engineer who supervised you
- A record matching each piece of evidence to the specific requirement it satisfies
That last point is the one people underestimate. Having the photographs is not the same as having a portfolio. Evidence that is not tied to a requirement is just a folder of pictures, and it is the most common reason a submission comes back for more work.
Who can sign off a gas portfolio?
A Gas Safe registered engineer who has supervised the work. Their sign-off is a statement that the work was carried out to the required standard — which means it follows the work. It is not a signature that can be issued for jobs that were never done, and anyone offering you one on that basis is not doing you a favour.
Your training centre then assesses the portfolio. They decide whether the evidence meets their requirements. The supervising engineer confirms the work happened; the centre decides whether it is enough.
What varies by training centre
A lot, and this is worth knowing before you take anyone's word for what you need. The number of jobs, the mix of appliance and job types, how the evidence must be presented and what counts as acceptable proof are all set by the centre and by which ACS units you are taking.
If someone tells you a gas portfolio needs a specific number of jobs, ask them how they know yours does. Check the paperwork issued through your training centre and the requirements that apply to your programme — those are what your evidence has to satisfy.
Why so many people get stuck
Almost nobody fails to finish a portfolio because the paperwork defeated them. They get stuck because they cannot get on site.
Supervising a trainee costs a working engineer time and money. They are running jobs to a schedule, a second pair of hands slows some of those jobs down, and the responsibility for the sign-off sits with them. There is rarely a fee in it. So the answer is usually no — not out of unkindness, but out of arithmetic.
The result is that people finish the classroom part, feel nearly qualified, and then spend months ringing round with the qualification sitting unfinished. That gap between "trained" and "certified" is where most people lose time.
Mistakes that cost people time
- Collecting evidence before checking the requirements. Doing the jobs first and reading the paperwork afterwards usually means some of the work does not count towards anything.
- Photographs that do not show enough. A picture of a boiler is not evidence. A picture of you working on that boiler, where the task is identifiable, is.
- Leaving the organising until the end. Matching months of photographs to requirements from memory is far harder than labelling them as you go.
- Assuming every centre wants the same thing. They do not, and building to somebody else's requirements is wasted work.
Can I get help if I haven’t started my portfolio?
Yes. A completely blank portfolio is fine, and it is where a lot of people begin. What matters is that we can see the requirements you are working to, so we know what evidence and which job types need to be planned.
That is different from not having started a recognised training route at all. Supervised on-site experience forms part of a training programme — it is not a substitute for one.
What to do next
Start with your own requirements. Find the portfolio paperwork your training centre issued and work out exactly what is still outstanding — which jobs, which evidence, how it needs presenting. Everything else follows from that, and it is difficult to plan anything until you know it.
If you have the paperwork but cannot get the work, that is the problem Gas Track Academy exists to solve: we take you out on live jobs alongside a Gas Safe registered engineer, capture the evidence as you work, help you organise it, and handle the sign-off once the required work is done.