Anyone else found the whole planning permission process completely opaque?

[WittyNavyFinch]

We're looking at a loft conversion and I've been trying to work out whether it's likely to get approved before we spend a boatload on architect drawings. Spoke to the council and got basically nothing useful.

So I've been looking at what our council has actually approved and refused over the last few years. Turns out you can see every application on their planning portal... what was proposed and whether it got through.

The patterns are quite interesting. Our council approves about 88% overall but it varies massively by area — one ward near us is 95%, another is 75%. And loft conversions have a noticeably lower approval rate than rear extensions, which I wasn't expecting!

I've ended up doing this for quite a few councils now so if anyone's going through the same thing and wants me to have a look at their area, happy to. Just drop your postcode and what you're planning.

It isn't about patterns of approvals. It is about application of policy and guidance.

It is much better to spend the money on pre-application advice from the council or first discussion with an architect or architectural technician or planning consultant than on a data based report that lists percentages of approvals.

Yeah, fair point. The actual decision absolutely comes down to policy compliance, and nothing replaces proper professional advice.

But most homeowners aren't at that stage yet. They're wondering whether it's even worth pursuing. If you can see that 9 out of 10 similar extensions in your area got approved, that's useful context before you spend £300+ on pre-app or an architect. That's all my data is trying to be - a starting point, not a substitute.

Honestly - your data tells you nothing.
Planning just doesn't work like that.
There are so many different factors that are taken into account, and they are different for every site and every proposal. I've been in the business nearly 40 years.

Just to reply to your statement that I've described exactly why local precident matters, yes but that is exactly why your data is irrelevant. It is not determined on an authority level, but a building by building level. Even if 75% of front dormers in my town would be approved, I know that there would be a 0% chance on my street. I only know this because I'm a qualified planning officer and am trained to make this determination, and it seems very disingenous to take people's money to provide them with data that means nothing and won't help them get planning permission or even as your suggest act as some sort of pre-app advice substitute to know if on their building their proposal is suitable. Incidentally I left planning for a number of years to start my own business, so from the other side of things yes, with good marketing you'll make money (and piss off a lot of planners who then have to listen to applicants complain that they were told they had an 82% chance of success when they've never spoken to this person before) but your reviews will likely be pretty poor once people realise that they paid for something that doesn't benefit their application. Also pre-app advice is still free from many authorities.

Fair points and I appreciate the perspective from someone who's worked in planning.

You're right that planning decisions are building-by-building, but I'm not claiming that ward-level data can replace professional judgement. I've moved away from giving percentage chances - the tool now shows patterns in how similar applications have been decided nearby, not predictions.

The use case I'm building for is the homeowner wondering whether it's even worth looking into an extension before they've spoken to anyone. Most people don't know pre-app exists, let alone that it's free from some councils. If my data helps someone see that their council refuses a lot of rear extensions and decide to get proper pre-app advice before spending money on drawings, that's a win.

Genuinely interested in your take on what would make this more useful rather than less. Always looking to improve it :)

If my data helps someone see that their council refuses a lot of rear extensions and decide to get proper pre-app advice before spending money on drawings, that's a win.

It doesn't work like that. You could have two identical proposals and one could get refused and one approved. Because - and I've mentioned this before - every site is different.
Identical proposals could be permitted development in one location and not in another.
Lots of applications could have been refused because a lot of unreasonable proposals were submitted.

A planner will likely have a degree and a post grad qualification before they can even begin the route to becoming chartered. They are professional experts. If people want advice, they can chat to the local council planners and/or employ a consultant. The information you have collated is of no relevance.