What Is a Planning Application and Why Should UK Plumbers Care?

I spent a couple of hours one afternoon pulling planning application data from a council portal - no grand plan, just curiosity. I wanted to understand what a typical month looked like for a single local authority area. Within thirty minutes I had nineteen approved applications in front of me: rear extensions, loft conversions, a couple of garage conversions, a new build plot. Not one of those addresses had a plumber lined up. The homeowners were weeks away from even thinking about Googling one.

That's when it clicked. Here was a list of people who had just been told they were allowed to build something - something that almost certainly needed plumbing work - and the entire plumbing industry in that area had no idea they existed. The data was public. Anyone could have found it. Nobody had looked.

Most plumbers find new work the same way they always have: word of mouth, Google reviews, maybe a bit of advertising. That's all fine - until you realise it puts you in a queue with every other plumber competing for the same customers who already know they need a plumber. Planning applications are different. They're a list of people who are going to need a plumber before they've started looking for one.

So What Actually Is a Planning Application?

In the UK, if you want to make significant changes to a property - a rear extension, a loft conversion, a garage conversion, a new build - you usually need permission from your local council before work starts. You apply for that permission through a planning application.

The council reviews the application, consults with neighbours, checks local planning rules, and either approves or rejects it. If approved, the homeowner gets a decision notice and can start looking for tradespeople to carry out the work.

Here's the bit most plumbers don't know: all of this is public record. Every application - submitted, pending, approved, or rejected - is published on your local council's planning portal. The portal shows the address, the type of work, the applicant's name, and often a description of exactly what's being built. In Scotland, this is managed through the national ePlanning Scotland system. In England and Wales, each council has its own portal, though the data is structured similarly.

You can search these portals right now, for free, with no account required. The reason most plumbers haven't is that the interfaces are clunky, the search filters are limited, and sifting through irrelevant applications (commercial properties, retrospective applications, minor works that need no plumbing) takes time they don't have.

Why Most Plumbers Have Never Thought to Look

The standard advice for plumbers trying to win more work goes something like this: ask for reviews, run Google Ads, get on Checkatrade, make sure your website comes up for "plumber near me." All of that is competing for people who already know they need a plumber and are already searching.

Here's my honest opinion: most plumber lead generation advice is just advice to compete harder for the same shrinking pool of ready-made leads. The homeowner types "plumber [town]" into Google, calls three numbers, picks the one who answers. You're in a race you didn't design and can't fully control.

Planning applications are a different category entirely. These are people who have been told, officially, that they're allowed to build something. The extension is approved. The loft conversion is approved. They need a plumber - they just haven't started looking yet. You're not competing with anyone because nobody else is paying attention.

The reason plumbers don't use this source isn't a secret about the industry. It's just that nobody has made it easy enough. Manually checking planning portals for your area, filtering for relevant job types, extracting addresses and writing personalised letters - that's a few hours a week of effort most sole traders don't have. So they default to the channels that feel easier, even if those channels are the most crowded.

What Types of Planning Applications Are Worth Your Time?

Not every approved application means plumbing work. Here's what to look for:

• Rear and side extensions - the most common type, and almost always involves a new kitchen, utility room, or relocated bathroom. Strong demand for boiler relocations, new radiator runs, and underfloor heating.
• Loft conversions - typically includes a new en-suite or bathroom. The conversion itself is often done first, then homeowners look for a plumber to sort the bathroom fit-out.
• Garage conversions - often converted to a utility room, home office with a toilet, or additional living space. Regularly needs a new water connection and drainage.
• New build plots (single dwelling) - full plumbing install from scratch. Higher-value job, but longer lead time and more competition from larger contractors.
• Garden outbuildings and annexes - increasingly common, especially after remote working became normalised. Annexes with toilets and kitchenettes need full plumbing connections.
• Commercial to residential conversions - offices or shops converted to flats. These often go through HMO licensing as well, which creates a long-term gas cert and maintenance relationship.

For a sole trader plumber, the sweet spot is extensions and loft conversions in the £5,000-£25,000 build budget range - the jobs where a homeowner is managing the build themselves rather than paying a main contractor, so they're sourcing tradespeople individually.

The Numbers - How Many Potential Jobs Are Being Approved Near You Right Now?

This varies by area, but as a rough guide: a medium-sized UK local authority area typically receives 300-600 planning applications per month. Roughly 30-40% of those are residential extensions, loft conversions, or new builds. Not all of them will need a plumber - but a significant proportion will.

Scenario	Number
Approved residential applications per month (typical medium authority)	~120
Percentage needing plumbing work	~60%
Leads worth contacting	~72/month
Response rate to a personalised letter (realistic)	8-12%
Conversations per month	6-9
Jobs booked (1 in 3 conversations)	2-3/month
Additional revenue per year (avg £600/job)	£14,400-21,600

Those aren't inflated numbers. The response rate is based on personalised outreach - letters that reference the specific project by address and job type - not generic leaflets. A letter that says "I see you've been approved for a rear extension on [street name] - if you need a plumber for the bathroom or kitchen relocation as part of that build, I'd be happy to quote" hits differently than a flyer through the door.

And the jobs you're booking are with people who haven't started Googling yet. You're the only plumber they've heard from.

What Do You Actually Do With a Planning Application?

The process for using planning applications as a lead source is straightforward, even if the manual version is time-consuming:

1. Find the application - search your council's planning portal for recently approved applications. Filter by application type (householder, full, prior approval) and by relevant decision date range.
2. Check if it's relevant - read the description. "Proposed single storey rear extension to form extended kitchen/living space" is a plumbing job. "Replacement of existing fence" is not.
3. Get the address - it's listed on every application. This is what you write to.
4. Write a personalised letter - mention the specific project. Reference the address. Keep it short: who you are, your Gas Safe number if relevant, what you do, an offer to provide a no-obligation quote. Include a phone number and website if you have one.
5. Post it - physical post. Not email, not a leaflet round. A proper letter in an envelope addressed to the property. It stands out because almost no one does it.
6. Timing - the window is roughly 2-8 weeks after approval. Too early and the homeowner is still dealing with architectural drawings and contractors. Too late and they've already found a plumber. A week or two after the decision notice is published is usually right.

The manual version - finding applications, filtering them, drafting letters, printing and posting - takes 3-4 hours a week if you're covering a reasonable area. The Planning Leads tool automates the monitoring and filtering, and delivers a weekly digest with letter templates ready to personalise and send. You spend 20 minutes, not 4 hours.

What the Best UK Plumbers Are Doing About This

The plumbers who are already using planning applications as a lead source share a few things in common. They're not doing mass outreach - they're being selective about which applications they respond to (the ones in their area, the job types they want). They're writing letters that reference the specific project, not generic mailers. And they're consistent - sending letters every week, not in a burst and then nothing.

The results aren't instant. A homeowner who gets your letter might file it away and call you six weeks later when the groundwork is done and the extension shell is up. That's fine - as long as you got there before they Googled a plumber, you're the name they already have.

The outreach channel works best as a steady background activity, not a campaign. It fits well alongside the other lead sources a sole trader relies on - word of mouth, Google reviews, a decent website. It just adds a stream of pre-need leads that no one else is competing for. See also: how UK plumbers can find jobs before anyone else does.

Frequently Asked Questions

Are planning applications really free to access?

Yes. Every UK council is required to publish its planning register publicly. You can search approved applications by area and date on your council's website at no cost. The data includes the address, applicant name, project description, and decision date. No account is needed to view approved applications.

Do I need permission to contact homeowners who've applied for planning permission?

Writing to an address listed in a public planning register is legitimate business outreach. The information is published specifically because planning decisions are a matter of public record. Keep your letter professional, don't reference any personal details beyond the address and project description, and include a clear way to opt out of future contact. Standard GDPR-compliant direct mail practice applies.

What types of planning application are most likely to lead to plumbing work?

Rear and side extensions are the highest-volume category and almost always involve some plumbing - new or relocated kitchens, bathrooms, utility rooms, or underfloor heating. Loft conversions regularly include a new en-suite. Garage conversions and garden annexes are less common but often include toilet and basin connections. New single-dwelling plots are higher value but more competitive.

How long after approval should I send a letter?

The sweet spot is roughly 1-3 weeks after the decision notice is published. Too early and the homeowner is still finalising builders and architects. Too late - more than 8-10 weeks - and they've usually started the project and already found trades. Planning applications often sit in the portal for a while before anyone acts on them, so monitoring recent approvals weekly gives you a consistent window.

Is this worth doing if I'm already fully booked?

If you're fully booked on reactive callouts and small jobs, planning outreach gives you a way to build a pipeline of higher-value project work alongside that. Extension and loft plumbing jobs tend to be better-margin than emergency callouts - they're planned, scoped, and usually involve multiple days of work. Even if you only convert one or two a month, the value per job justifies the effort. It's also worth doing now rather than later - this channel is currently underused. The longer you wait, the more likely competitors in your area start using it too.

Here's the thing nobody in the plumbing trade is talking about yet: planning applications are public data. Every approved extension, loft conversion, and new build in your area is sitting in a council portal, searchable by anyone who can be bothered to look. Most plumbers never look. The ones who do - and who reach those homeowners before they've Googled a plumber - win jobs they didn't have to compete for. We're automating that process. If you want early access, the waitlist is at plumberproai.co.uk/planning-leads

Written by Alexander McVicar