New boiler paperwork: Benchmark, Building Regs and your warranty
Three separate documents, three different jobs. What the Benchmark Checklist proves, when your Building Regulations certificate should arrive, and what to chase if it never does.
16 August 2026 · 6 min read
After a boiler installation you should end up with three separate pieces of paper, and almost nobody explains which is which. They get lumped together as the certificate, so when one of them fails to turn up, people either do not notice or chase the wrong thing.
They are not interchangeable. One is filled in by your installer on the day, one is issued by a government-backed scheme weeks later, and one you or your installer have to register with the manufacturer. Miss the third and the warranty on a brand new boiler is worth nothing.
Here is what each one is, when it should reach you, and what to do if it does not.
1. The Benchmark Checklist
This is the one your installer completes at your kitchen table on the day. It lives in the back of the installation instructions that came in the box with the boiler, and it is the commissioning record: the gas rate, the flue gas readings, the system pressure, whether the system was flushed and what inhibitor went in.
Benchmark is run by the Heating and Hotwater Industry Council. The installer is required to complete it as a means of demonstrating compliance with the Building Regulations in England and Wales, and you are asked to sign it to confirm you were given a full explanation of how the thing works. There is also a space on it for the Building Regulations notification number, which is worth chasing at the time rather than a year later.
Two practical points. Keep the whole booklet, not just the loose page: the Service Record is printed in the same document, and that is what keeps the warranty alive. And check it has actually been filled in before your installer leaves, because a blank Benchmark section is the single most common paperwork problem we see.
2. The Building Regulations Compliance Certificate
Fitting a boiler in England or Wales is notifiable building work. Your Gas Safe registered installer notifies it through Gas Safe Register, which passes it to your local authority building control department, and a certificate is then issued to you.
The timings are worth knowing because they explain why nothing arrives for weeks. Under the Building Regulations the local authority should receive notification of the work within 30 working days of completion, and the compliance certificate should reach the householder within 10 to 15 working days of that notification. Since 2023 it can be emailed rather than posted, so check your junk folder before you chase.
If nothing has arrived roughly six weeks after the job, ask your installer for the notification number. If they cannot produce one, that is the moment to press, not six months later.
Source: Registered Gas Engineer (Gas Safe Register), gas safety and Building Regulations compliance certificates; Gas Safe Register, new gas appliance installation
3. Warranty registration
This is the one that catches people out, because it is not automatic and it is not the installer's legal duty. Manufacturers set a window for registering the guarantee, commonly 30 days from installation, and registration is normally conditional on the boiler having been installed and commissioned properly by a suitably registered engineer.
Plenty of good installers register it for you as a matter of course. Plenty of others assume you will. Ask the question on the day, and if the answer is anything other than a clear yes, register it yourself online with the serial number off the boiler.
The part that costs people money later
Registering the warranty starts it. The annual service is what keeps it running, and the Benchmark Service Record is the proof.
Manufacturers are explicit about this. Worcester Bosch, to take one example, states in its own user instructions that a call-out charge will be made where evidence cannot be provided that the first year service inspection has been carried out, meaning an entry in the Benchmark Checklist. So the boiler can be two years old, still inside a ten year guarantee, and you can still be charged for the visit because nobody stamped the book.
Every service, make sure the engineer completes the Service Record. It takes thirty seconds and it is the difference between a free repair and a bill.
What none of these are
A gas safety record, sometimes called a CP12, is a different document again. That is the annual safety check a landlord is legally required to have carried out on a rented property. It is not a boiler installation certificate, and having one does not mean the installation was ever notified.
If you are buying a house and the seller hands you a gas safety record in place of a Building Regulations certificate, those are not the same thing and your solicitor will treat them differently.
Who is actually on the hook if it was never notified
This is the bit that surprises people. On the pure gas safety side, the responsibility for the work sits with the registered engineer. But the Building Regulations side is different: the householder is liable for work covered by the Building Regulations, as the person who procured the work.
There are two enforcement routes and both are time limited. A local authority can serve an enforcement notice requiring the work to be altered or removed, but not more than 12 months after the building work was completed. Prosecution for contravening the Building Regulations can be brought up to two years after the work was completed, and in a Magistrates Court the fine is unlimited.
In practice, for a straightforward domestic boiler swap this almost never gets that far. The real world cost of missing paperwork is much more mundane: a stalled house sale, a refused warranty claim, and a buyer's solicitor asking questions you cannot answer.
A sensible timeline to hold your installer to
- On the day: Benchmark Checklist completed and signed, manual and instructions handed over, controls demonstrated.
- On the day: ask whether they are registering the manufacturer warranty or whether you are.
- Within a week: the notification should have been made. Ask for the number and write it on the Benchmark Checklist.
- Within about six weeks: the Building Regulations Compliance Certificate should have arrived by post or email.
- Every 12 months: annual service, with the Service Record in the Benchmark booklet completed each time.
If you have just moved in and there is nothing
The most common version of this we come across locally is not a bad installation at all. It is somebody who bought a house around Northampton or Milton Keynes with a boiler that was fitted by the previous owner, and no paperwork came with it. Sometimes it was a landlord install and the documents went to a letting agent. Sometimes the boiler is old enough that the manual went in a skip.
You are not stuck. Gas Safe Register can confirm whether an installation at your address was notified, the manufacturer can usually tell you the boiler's age from the serial number, and a good engineer will start a fresh Service Record at the next service. What you cannot do is retrospectively create a Benchmark commissioning record for work you did not witness, which is exactly why it matters to get it right on the day when it is your own installation.
The short version
Benchmark proves it was commissioned correctly and keeps your warranty valid. The Building Regulations Compliance Certificate proves it was notified, and it is the one a buyer's solicitor will ask for. Warranty registration is separate from both and has a deadline.
Get all three, keep them in the same drawer as the manual, and make sure the Service Record gets stamped every year. It is five minutes of admin that decides whether a ten year guarantee is real or decorative.
If you are getting quotes for a new boiler around Northampton and Milton Keynes, we can put you in front of Gas Safe registered installers who will hand over the paperwork properly.