Reading a statutory instrument that amends the GPDO
An amending order is a set of editing instructions, not a readable rule. The skill is applying it to the principal order and knowing which version governs your case.
Reading a GPDO amendment order is a mechanical skill and it takes about twenty minutes to learn. An amending statutory instrument does not tell you what the permitted development right now says. It tells you which words to insert, substitute or omit in the principal order, and leaves you to do the editing. Apply the instructions in the wrong version of the principal text, or to a version that has since moved on, and you will advise a client that works are permitted when they are not.
The General Permitted Development Order 2015 has been amended many times. Any statement about what a class permits is a statement about a particular version of that order on a particular date, and saying which date is part of giving the advice.
How an amending order is put together
Open any amendment order and the anatomy is the same.
Article 1 gives the citation, the date it comes into force and the extent, which for these instruments is England. Read the date carefully, because different articles sometimes come into force on different days.
Article 2 onwards contain the amendments, written as editing instructions. In Schedule 2, Part 1, Class A, in paragraph A.1, after sub-paragraph (f) insert the following. In Part 3, omit Class MA and substitute. The instruction refers to the principal order by its full structure: schedule, part, class, paragraph, sub-paragraph.
Where the amendment adds a whole class, it appears as a block of text set out in quotation marks or in a schedule to the amending order.
At the end sits an explanatory note, which is not part of the instrument and is reliable for orientation rather than for advice. Read it first anyway, because it tells you in three sentences what the order is trying to do, which makes the editing instructions much easier to follow.
The explanatory memorandum published alongside the instrument goes further, giving policy background and sometimes the intended practical effect. Useful context, not law.
Finding the consolidated text as amended
You rarely want to do the editing by hand. The revised version of the principal order on legislation.gov.uk already incorporates most amendments.
Three things to check every time you open it.
Which version you are looking at. The site distinguishes the original text as made from the latest available revised text, and the header tells you which is on screen.
Whether there are outstanding effects. A banner or a changes to legislation panel lists amendments that have been made but not yet applied to the revised text. Where a recent amending order is listed as not yet applied, the consolidated text you are reading is behind the law, and you have to go to the amending instrument and apply it yourself.
Which date the text speaks as at. The point in time feature lets you view the order as it stood on a chosen date, which is indispensable for a lawful development certificate concerning works carried out years ago. Those are judged against the law in force when the works were done, not the law today.
That last point is the one that separates a careful practitioner from a confident one. A certificate application for a 2016 outbuilding is an exercise in historical research, and the point in time view is the tool for it.
Class letters, paragraph letters and why they look odd
The structure looks arbitrary until you see why it is that way.
Schedule 2 is divided into Parts by subject: Part 1 for development within the curtilage of a dwellinghouse, Part 3 for changes of use, Part 14 for renewable energy equipment, Part 16 for communications, Part 20 for new dwellings on existing buildings. Each Part contains Classes, lettered A, B, C and so on.
When a new class is inserted, renumbering the existing ones would break every document that cites them, so drafters use doubled letters instead. That is why Part 1 contains Class AA alongside Class A, and Part 3 contains Class MA. A class beginning ZA is generally a later insertion placed at the start of a part.
Within each class the structure repeats. The class itself states what is permitted. The paragraph numbered with the class letter and .1, so A.1, sets out the limitations, with sub-paragraphs (a), (b), (c) and onwards. The paragraph numbered .2 sets out conditions. The paragraph numbered .3 or .4 often covers interpretation and prior approval procedure.
So a citation like Schedule 2 Part 1 Class A A.1(f) is precise and worth using in full. Half the disputes about householder permitted development are really disputes about which sub-paragraph applies.
Articles in the body of the order matter too, and amendments insert new ones there as well. The fire statement duty sits in an article inserted into a different order entirely, the procedure order, which is the pattern described in planning gateway one and article 9A of the DMPO.
Checking whether the amendment is in force for your case
Coming into force and applying to your case are separate questions.
An amending order states the date it takes effect. It will often also carry transitional or saving provisions, expressed in terms that matter enormously: does not apply to development begun before that date, does not apply to a prior approval application made before that date, applies only to buildings constructed before a stated date.
That third form is common in the classes that convert existing buildings, where the right is limited to buildings in a particular use on a particular historic date. Those qualifying dates are part of the substantive right rather than a transitional provision, and they do not move when the class is amended unless the amendment says so.
Work through four questions for any specific proposal. Is the amended class in force. Does a transitional provision exclude this case. Does the site meet any qualifying date or use condition in the class. And has an article 4 direction or a condition on an earlier permission withdrawn the right locally.
The change to the use classes system in 2020 is the clearest illustration of how much turns on transitional wording, and the detail is set out in what the 2020 amendment changed for Class E.
Why the printed guidance lags
The government publishes technical guidance on householder permitted development rights, and it is useful for the interpretation of terms like original dwellinghouse, principal elevation and curtilage.
It is guidance about the order, published separately from it, and it is revised on its own schedule. After an amendment there is usually a period in which the order has changed and the guidance has not. Third-party summaries lag further still, and a printed guide or a saved PDF is a snapshot of a moment.
Use the guidance for interpretation and the order for the rule. Where the two appear to conflict, the order wins, and that is worth saying explicitly in any advice note that relies on the guidance.
The planning law updates timeline is a reasonable place to follow what is changing, though for anything you will rely on, go to the instrument itself.
Recording the version you applied
On any submission that depends on a permitted development right, record six things in the file and, where relevant, in the covering statement:
- The principal order by full title and year.
- The words as amended and the date the text you read was current to.
- The Schedule, Part, Class and paragraph relied on, cited in full.
- Any amending instrument applied by hand because it was not yet incorporated.
- The article 4 position for the address, with the direction reference where one exists.
- The date you checked, and by whom.
Six lines. They take five minutes and they answer the question that arrives when a case officer disagrees with you, or when a lawful development certificate is challenged three years later.
A certificate remains the only formal way to confirm that works are lawful, so where a client is relying on permitted development for anything substantial, advise them to apply for one. The index of report types by category sets out the supporting documents an application is likely to need.
This is general guidance, not legal advice. Check the current text on legislation.gov.uk and the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.
Frequently asked questions
Where do I find the GPDO as currently amended?
On legislation.gov.uk, using the revised version of the General Permitted Development Order 2015 rather than the original as made text. Check the changes to legislation panel for amendments that have been made but not yet applied, because where one is listed the consolidated text on screen is behind the law.
Why are there classes called AA and MA?
Because renumbering existing classes when a new one is inserted would invalidate every citation in circulation. Drafters insert doubled letters instead, so Part 1 has Class AA alongside Class A and Part 3 has Class MA. A class beginning ZA is usually a later insertion placed at the start of a part.
Which version of the rules applies to works carried out years ago?
The law in force when the works were done. Use the point in time feature on legislation.gov.uk to view the order as it stood on the relevant date. This is essential for a lawful development certificate for existing use or development, where the question is whether the works were lawful at the time.
Can I rely on the government technical guidance?
For interpretation of terms such as original dwellinghouse, principal elevation and curtilage, yes. It is guidance about the order rather than the order itself, and it is revised on its own schedule, so after an amendment it may lag. Where guidance and the order conflict, the order governs.
What should a submission record about the version relied on?
The principal order by full title and year, the words as amended with the date the text was current to, the Schedule, Part, Class and paragraph cited in full, any amendment applied by hand, the article 4 position for the address, and the date you checked. Six lines that answer later challenges.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.