DevilDamo

The only permitted front extension you can have without Planning is a porch… https://www.planningportal.co.uk/permission/common-projects/porches/planning-permission

Are you adding an additional storey to provide a 3-storey dwelling?

It’s more for the fire brigade to access the window as opposed to an occupant hanging and/or jumping out.

If the Council pick up on the extension, deal with it then. No point making them aware of it now. They “should” know that after 4 years, it’s lawful anyway. Whether they want to go to the trouble of asking you prove that, then I’m sure that wouldn’t be too difficult… especially as you’ve been there for about 4 years already. Just focus on the loft works and decide whether or not you want to submit a Certificate of Lawfulness application.

The actual PD term of 50% relates to the amount of land around the original house should not be covered by extensions, additions, etc… It appears you’re referring to single storey side extensions should be no greater than half the width of the original house. So if your original/as-built house has a width of 8.4m, then you can add single storey side extensions to each side of max. 4.2m wide. There are of course other PD requirements to adhere to.

What does any of that have to do with felling trees prior to the submission of an application?

You may be waiting a long time because… - Foundation information relates to Building Regulations, not Planning. - If you were to contact Building Control, they would state you need to dig trial holes as old records are far too old to be relied upon.

Not needed to submit the application but may be required and requested during the plan check stage and will enable a completion certificate to be issued.

If the proposals required Planning, the LPA will have them. They’re just not online (yet).

You will require Planning and providing the increase in height does not have a significant impact on the street scene and/or on neighbours, then there should be no reason why Planning would not be approved.

On the assumption you had an appointed an agent, can you ask them? May not want to open up a can of worms with the Council unless it’s purely an admin error of which your agent could confirm?

https://www.wilsonbrowne.co.uk/news/what-constitutes-development/

Why would BR’s apply if there are no structural changes?

All of the above and depends what mood the Planning Officer is in. Does your LPA have their own policies and guidance which relates to and states the relationship? There may also be similar guidance within the NPPF.

You would need to submit a newrevised application.

I agree with the LPA’s decision. PD/PA isn’t always clear cut and straight forward. Your options are to apply for Full Planning or remove the part of the conservatory/roof that would end up connecting to the new extension. Bear in mind that would need to be removed prior to any re-submission.

Just like how pro-active and informative the Planning Pre-application process is.

In terms of Planning, you’re assuming they would carry out an inspection of the completed building, which they wouldn’t. Your potential issue could be if/when a Building Regulation application is submitted. Some LPA’s allow annexe’s with self contained facilities while others do not. I’ve been on the receiving end of both which makes it more difficult to try and explain the reasons for refusal to clients.

You would normally have three options in order to make changes… 1. Non-material amendment 2. Variation of Condition 3. Householder/Full application Option 1 - I don’t think the LPA would treat that change as a minor amendment. LPA’s have their own views on what they would consider as non-material. There would be a fee and a determination period of approx. 4 weeks. Option 2 - A common way to vary/change a condition of which you would vary the condition that relates to the approved drawings. There would be a fee and a determination period of approx. 8 weeks. Option 3 - This would be a revised application of the one you had submitted and received approval for. You didn’t mention whether it was a Householder or Full application. You may be exempt from paying a fee and there would be a determination period of approx. 8 weeks. Depending on the conditions attached to your approval, you may also have the option of submitting a Discharge of Conditions application. But only if there is a condition that specially relates to submitted details and/or samples of the proposed materials.

That was Guildford, Surrey.

Although quite rare, the size(s) can come into it.

Yep, that may be the one 🤪 I initially read and interpreted that as in the construction, not the design. You can finish and clad a building to look however you want.

How about this? Utility accessed via the Kitchen along with a rear door. Worktop within Utility indicated in blue. W.C. or Shower room accessed via the Utility. Within the Shower room, you could have the shower on the right (backing onto the Kitchen), a washbasin on the side wall and then the W.C. to the rear with a window above.

A barn to accommodate what… a house?

Pardon? You’re asking to predict something that may or may not happen in the future. You won’t know the answers to your questions until you submit an application. I’m with @Kelvin on this and cannot see how or why the information you are trying to seek is going to help you.