For gas engineers
A gas certificate app for engineers working for themselves
Write the landlord's gas safety record on the job, and invoice the same visit from the same place.
What it does on a gas safety check
- Write the record on the doorstep, and save a draft mid-job.
- Any missing particular is named before a record can go out.
- The next due date counts from the last deadline, not your visit.
How each part works
Write the record on the doorstep, not on a pad in the van. Fill it in appliance by appliance: description, location, outcome, and what was wrong with any that failed.
It saves as a draft while the boiler is still apart. A job cut short halfway does not start again.
It will not let an incomplete record out. Each particular regulation 36(3)(c) lists is checked before a record can be issued. Anything missing is named, with the sub-paragraph it comes from.
A pad will happily let you sign a record with no registration number on it.
The next deadline is worked out, not guessed. It counts from the previous deadline, not the day you attended. So an early check does not quietly walk the landlord's anniversary backwards.
Certificates coming up for renewal show against the property.
Each issued record carries a code. A landlord, agent or tenant can enter it, with no account, to see what was issued, by whom and when. It reports what was issued, not whether it is valid.
Your own qualifications, scheme memberships and insurance sit in the app with their expiry dates. So a registration coming up for renewal shows before it lapses, not after.
The record, the quote, the photographs and the invoice stay attached to the address, not to whichever pad was in the van. That counts when a letting agent asks for last year's record on a flat you saw once, in February, in the rain.
The law sets what the record holds, not how it looks
Regulation 36(3)(c) sets what a landlord's gas safety record has to contain. It says nothing about how it is laid out. So a record written on a phone is the same instrument as one written on a pad.
What the record carries, and who gets a copy
Regulation 36(3)(c) lists what the record has to carry.
| Where it says so | |
|---|---|
| The date the check was carried out | Regulation 36(3)(c)(i) |
| The address of the premises | Regulation 36(3)(c)(ii) |
| The landlord's name | Regulation 36(3)(c)(iii) |
| The landlord's address | Regulation 36(3)(c)(iii) |
| At least one appliance or flue | Regulation 36(3)(c)(iv) |
| A description, a location and an outcome for every appliance, and what was wrong with any that failed | Regulation 36(3)(c)(iv) to (vi) |
| Your confirmation that the check met regulation 9 | Regulation 36(3)(c)(vii) |
| The name of the engineer who checked it | Regulation 36(3)(c)(viii) |
| The engineer's signature | Regulation 36(3)(c)(viii) |
| The Gas Safe registration number | Regulation 36(3)(c)(ix) |
Who gets a copy, and by when, is set out in regulation 36(5) and (6).
| What is required | Where it says so | |
|---|---|---|
| An existing tenant | A copy of the record is given within 28 days of the date of the check. | Regulation 36(6)(a) |
| A new tenant | A copy of the last record for each appliance or flue is given before that tenant occupies the premises. | Regulation 36(6)(b) |
| Anyone in lawful occupation | The record, or a copy, is made available for inspection on request and on reasonable notice. That is for a person who may be affected by an appliance the record covers. | Regulation 36(5) |
The widely repeated line that a landlord keeps the record for two years is not here in that form. Regulation 36(3)(c) keeps it until there have been two further checks. The two year rule covers the case where the appliance or flue has been removed.
The next deadline is not 12 months from the day you attended
The obvious rule is 12 months from the day of the check. It is quietly wrong in a lot of diaries, and wrong in the way that costs the landlord. Regulation 36A says something else.
Read regulation 36A, and why the app counts this way
| What it does | Where it says so | |
|---|---|---|
| Checked early | A check completed within the 2 months ending with the deadline date is treated as having been made on the deadline date. The next 12 months run from the deadline, not from the day you attended. | Regulation 36A(1) |
| Checked late, to line two appliances up | The landlord may instead check within the 2 months beginning with the deadline date. That may be used only once per appliance or flue. It may be used only to line up its deadline with another appliance in the same premises. | Regulation 36A(2) and (3) |
Count it the easy way for five years and the anniversary walks back by weeks. All of that comes off the landlord's compliance runway, and nothing anywhere looks broken. Counting from the previous deadline stops that.
Where every rule on this page comes from
- The Gas Safety (Installation and Use) Regulations 1998, regulation 36SI 1998 No. 2451. Paragraph (3)(a) sets the interval of not more than 12 months. Paragraph (3)(c) lists the nine particulars a record must carry, at (i) to (ix). It also sets the retention rule: until there have been two further checks. Or, where the appliance or flue has been removed, two years from the last check. Paragraphs (5) and (6) cover who gets a copy and when.
- The Gas Safety (Installation and Use) Regulations 1998, regulation 36AInserted by SI 2018 No. 139, in force 6 April 2018. Paragraph (1) treats a check completed in the two months ending with the deadline date as made on the deadline date. Paragraph (2) allows a check in the two months beginning with it instead. Paragraph (3) limits that to once per appliance, and only to align deadlines within the same premises.
- HSE: landlords' gas safety responsibilitiesThe Health and Safety Executive's own answers on the duties in regulation 36, including what a landlord has to hold and hand over.
- Making Tax Digital for Income TaxHMRC's guidance on the qualifying income thresholds, the dates each band starts from, and the software HMRC recognises.
This page states the regulations as read on legislation.gov.uk, not from a summary. It is not legal advice. Whether a duty applies to a job turns on the premises, the tenure and who commissioned the work. Sources last read 4 September 2026.
Where it stops on a gas job
- It does not make you or a record Gas Safe registered. The registration behind your signature makes a record valid, and that sits with the scheme. It prints your number, but does not check it or link to the register.
- It does not write an EICR, an EIC or an unvented hot water certificate. Those are not single-job forms. A minor electrical works certificate is written here.
- It has no job dispatch, shared diary or tracking of other engineers. It is made for one engineer who does the checks and the paperwork.
- It needs a signal, with no offline mode. A record written in a basement plant room with no signal has nowhere to go until it comes back.
What it works out once the jobs are in it
| What it tells you | Shown once you have | |
|---|---|---|
| Revenue per available working day | Money received in a period divided by the working days that period actually held, taken from the working pattern the trader sets. The trades equivalent of a hotel's revenue per available room, and it decomposes the same way: effective day rate multiplied by utilisation. | 5 available working days and at least one booked day in the window |
| Why revenue moved | The change in invoiced revenue against the previous 30 days, split into ranked contributing factors: how many jobs were invoiced against what the typical job was worth, with quotes sent as upstream context. | 2 invoices in each period and a change of at least 15 per cent |
| Quote speed against win rate | Whether quotes the trader sends within 24 hours convert better than the ones they send later, measured on their own decided quotes rather than on a general rule of thumb. | 3 decided quotes in each bucket and a gap of at least 10 percentage points |
| Margin per job over time | One point per won job, priced against its materials and subcontractor cost, plotted by job date and split weekday against weekend so an out-of-hours premium can be checked rather than assumed. | 5 won jobs with a recorded cost, and 3 in each of the weekday and weekend buckets before the split is drawn; jobs with no recorded cost are excluded, not counted as zero |
| Quote win rate | The share of decided quotes that were accepted, shown with a Wilson score interval and the sample size, so the figure carries the range it could really be. | 10 decided quotes |
| Utilisation | Days booked against days available. Deliberately uncapped, so a weekend worked reads as over 100 per cent rather than being flattened to a full week. | a working pattern set, and 5 available working days in the window |
| Time to get paid | A value-weighted days-sales-outstanding figure, so one large invoice paid late moves it more than several small ones do. | 3 paid invoices |
| Typical job value | The median value of a won job, not the mean, so a single unusually large job does not redefine what typical means. | 3 won jobs with a recorded price |
| Time from quote to job | The median gap between sending a quote and the work starting, which is the lead time a trader is really working to when they fill a diary. | 3 won quotes with both dates recorded |
What it costs
Pro is £29 a month or £290 a year, with no per-seat fees and no contract. Every new account starts on a 14 day free trial of Pro with no card needed, and drops to the free tier rather than switching off.
Frequently asked questions
What is a gas certificate app?
A place to write the landlord's gas safety record on the job, not on a pad. The quote, photographs and invoice for that visit sit with it. For a sole trader, the point is one visit's record and invoice in one place, not running a team.
Is there a gas engineer app, or is it a website?
It opens in the browser on your phone, so there is nothing to install and nothing to update. It was built around writing a record on a doorstep. That is why a part-finished record saves as a draft, and need not be done in one go.
Does it issue a CP12?
It writes a landlord's gas safety record, the document the law names. CP12 stands for CORGI Proforma 12, a commercial pad brand, not a statutory form. Regulation 36(3) sets the record's content, not its layout, so one with the nine particulars is a record, whatever the pad looks like.
How long does a landlord have to keep the record?
Regulation 36(3)(c) requires it to be kept until there have been two further checks of that appliance or flue. The two year rule people often quote applies where the appliance or flue has been removed from the premises. It runs from the date of the last check.
When is the next check due if I attend early?
Under regulation 36A(1), a check in the 2 months ending with the deadline date is treated as made on that date. The next 12 months run from that deadline, not your visit. The app counts from the previous deadline, or the anniversary slips back a little each year.
Does it keep track of my Gas Safe registration?
Your qualifications, scheme memberships and insurance documents are kept with their expiry dates. So you can see a registration about to lapse before it does. It does not renew anything, check your number or connect to the register.
What happens to the records I have written if I stop paying?
You can still open your own data and export it. A landlord can rely on a gas record for years, and a sole trader has to keep business records well past the filing deadline. An app that strands them when a subscription ends is a problem, not a feature.
Does My Job Goblin tell me whether I am actually making money?
Yes, and that is the half most job software leaves out. It records the quote and the invoice like anything else, then does the arithmetic on top: revenue per available working day, margin per job against materials and subcontractor cost, quote win rate with the range it could really be, and how long customers take to pay weighted by the size of the invoice. Turnover on its own hides all four. No figure is shown on a sample too small to support it. Where there is too little history the card renders nothing, rather than a number with a caveat underneath it.
What is revenue per available working day?
It is what a day of your available time earned, rather than what you charged for a day you worked. Take the money received in a period and divide it by the working days that period held, from the working pattern you set. Hotels have measured this for decades as revenue per available room, because a room nobody booked is revenue that can never be recovered. A Tuesday you did not fill is exactly the same thing. My Job Goblin decomposes it the way a hotel does, into your effective day rate multiplied by your utilisation, so you can see which of the two moved.
Does it compare my prices against other tradespeople?
No, and that is deliberate. There is no benchmarking against other businesses. Trades publish no prices, day rates or availability in any machine-readable form, so a peer comparison in this market is either a very small sample or an invented one. Every figure compares a trader against their own history. A benchmark against a handful of unrepresentative businesses, or against a number nobody can source, is worse than no benchmark at all.
What does the free tier include?
The free tier runs 3 quotes and 3 invoices a month, end to end: build the quote, send the PDF, let the customer approve it in the portal, and invoice it. The AI pricing and description tools, expense tracking, certificate filing and reports are Pro. The HMRC year-end tools are Pro + Tax. The cap is small on purpose. A free tier big enough to run a trade on has to be paid for by the traders who do pay, and they are one-person businesses on a flat £29 a month with no per-seat fee. What the free tier proves is the whole loop rather than the volume: build the quote, send it, let the customer approve it, invoice it.