# Working in Wales - planning rules you need to know
Planning in Wales looks similar on the surface, but the rules underneath are not a copy-and-paste of England. If you use English planning guidance for a Welsh job, you can very easily mis-advise a client or build something that needs permission when you thought it didn't.
Wales has its own policies, its own guidance notes, and different Permitted Development rights. If you work near the border, you need to treat Welsh planning as a separate system, not a variation of the English one.
1. The planning rulebook in Wales
In England, you're used to hearing about the NPPF and the Planning Practice Guidance. In Wales, the core documents are different.
The key pieces are:
- Planning Policy Wales (PPW) - Wales' version of the National Planning Policy Framework.
- Technical Advice Notes (TANs) - sit under PPW and give detailed guidance on specific topics (housing, design, transport, etc.).
- Local Development Plans (LDPs) - each Welsh local planning authority has its own LDP with local policies and site allocations.
The important bit: when you're planning in Wales, PPW + TANs + the LDP is the combo that matters, not the English NPPF and guidance.
If an architect, planning consultant or homeowner starts quoting "what the NPPF says" on a Welsh scheme, your first thought should be: "Wrong country."
2. Permitted Development in Wales is NOT England
This is where most trades and homeowners get caught out.
Everyone's got a mate who's "done a loft without planning" or "stuck an extension on under Permitted Development" in England. The problem is, the limits and conditions for PD in Wales are different.
Key things that can differ between England and Wales:
- Maximum size and depth of extensions
- Maximum height of extensions and outbuildings
- Rules for side extensions
- How much of the garden you can cover
- When prior approval is needed
- Special rules for roof enlargements, dormers and outbuildings
So you might have:
- A rear extension that is PD in England but needs full planning in Wales.
- An outbuilding size that is fine in an English garden but over the limit in a Welsh one.
- A loft dormer that triggers different conditions.
If a homeowner in Wales jumps on Google, lands on the English Planning Portal householder guide, and assumes that applies to them - they're rolling the dice.
3. Technical Advice Notes (TANs)
In England, you might reach for Planning Practice Guidance (PPG) or old Circulars for detailed planning advice. In Wales, that detail often lives in the Technical Advice Notes (TANs).
TANs cover things like:
- Housing density and mix
- Design and place-making
- Transport and access
- Environmental and situation issues
- Renewable energy and low-carbon design
You don't need to memorise them. What you need to know is: if someone is talking about planning guidance on a Welsh project and they're quoting English PPG or old English Circulars, that's a red flag. The decision-makers in Wales will be looking at PPW and the relevant TANs, not English documents.
4. Why using English planning info in Wales is a real problem
This is the real-world risk. A tradesperson or homeowner might:
- Google "single storey extension permitted development"
- Land on an English Planning Portal guide
- Read the English size and height limits
- Decide "we don't need planning"
- Build in Wales on that basis
At that point, you can end up with:
- A complaint to the council
- An enforcement inquiry
- A retrospective application you weren't planning on
- Conditions or changes imposed after you've finished the work
- In the worst case, a requirement to alter or remove what's been built
For you as the builder, that's stress, time, and potential cost you didn't price in - plus damage to your reputation even if the mistake started with the client.
It's not enough to say "but that's what the Planning Portal said" if what you were reading was the English site and you're standing on a Welsh plot.
5. How to handle Welsh planning in practice
You don't have to become a planning consultant. You just need a few solid habits when you're working in Wales.
Always confirm: "This site is in Wales, so Welsh planning rules apply."
Don't rely on English Planning Portal householder guides for Welsh jobs.
If the client quotes something they read online, ask: "Was that definitely about Wales, or was it England?"
When checking PD or policy:
- Use official Welsh Government or local authority sources.
- Check the relevant local planning authority's website (it will be a Welsh council).
For anything borderline: treat it as "planning may be needed" and get written confirmation from the local planning authority or a competent planning consultant who knows Welsh rules.
The mindset shift is simple: same island, different system. Treat Welsh planning as its own thing from day one, and you avoid being the one who told a client "you don't need permission" when in fact they did.
Pre-start planning checklist for Welsh jobs
Use this before you tell anyone "it's Permitted Development" or "you won't need planning."
1. Confirm you're actually in Wales
Check the full site address and postcode - don't guess off a Google Map smear near the border. Write it on the job file: "Jurisdiction: Wales (Welsh planning system)." Say it out loud to the client and designer.
2. Stop using English links and leaflets
Do not use the English Planning Portal householder guides for Welsh jobs. If the client sends you a link, ask: "Is that from a Welsh site or the English Planning Portal?" If it's clearly England-only, park it.
3. Check the local planning authority
Confirm which Welsh council you're dealing with. Make a note of the council name and their planning/householder guidance page. If you're unsure on PD or policy, that council's guidance is your first port of call.
4. Treat Permitted Development as different by default
Before you say "that's PD" on a Welsh job, ask yourself:
- Am I looking at Wales-specific guidance for PD limits and conditions?
- Have I checked the size, height and position rules for Wales, not just what I know from England?
- Is there anything about prior approval in Wales for this type of work?
If the answer to any of those is "not sure," your line to the client is: "It might be PD, but this is Wales, so we need to check it under Welsh rules before we assume anything."
5. Make sure designers and planners are on the same page
Ask your architect / designer / planning consultant: "Are you working from Planning Policy Wales and the local Welsh plan, not the English NPPF stuff?"
If they send you a planning note, scan it for clues:
- Mention of "NPPF" or English Planning Practice Guidance = challenge it.
- Mention of "PPW," "TAN" and the right Welsh council = better sign.
6. How you talk to the client
When a homeowner asks "Do I need planning?" on a Welsh job, your safe script is:
"Because this is in Wales, the rules are different to England. You might be okay under Permitted Development, but we need to check it against the Welsh PD rules and your council's guidance. I don't want to tell you it's fine and then have the council come knocking."
Helpful, but you're not guaranteeing something you can't guarantee.
7. When in doubt, get it in writing
If it's anywhere near the line, suggest the client gets either:
- Pre-app advice from the Welsh local planning authority, or
- A short note from a planning consultant who knows Welsh rules.
Make sure any "you don't need permission" advice is in their name, not just you saying it on a handshake.
Pin this up: the one-pager for your van
- Write on the job: "Jurisdiction: Wales (planning)."
- Don't use English Planning Portal guides to call PD in Wales.
- Check the Welsh council's own planning pages.
- Assume Welsh PD rules are different until you've checked.
- Ask designers: "Are you using PPW/TANs, not the English NPPF?"
- Tell clients: "We'll check this under Welsh rules before assuming PD."
- For borderline stuff, get planning advice in writing.
You follow this, and you stop being the one who "promised" a Welsh job didn't need planning when it actually did.
What to do next
- Read: Working in Wales - building regulations differences you need to know
- Read: SiteKiln Building Regulations guides (England)
- Check: Welsh Government planning portal for current Welsh PD rights and guidance
Sources (UK)
- Planning Policy Wales (PPW) - Welsh Government, the Welsh equivalent of the NPPF.
- Technical Advice Notes (TANs) - Welsh Government planning guidance by topic.
- Welsh Permitted Development rights - different limits and conditions from England.
- English Planning Portal - for England only, not to be used for Welsh jobs.
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