6mt full width extn. ridiculousness - again

11 Feb 2009
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United Kingdom
WTF ... is it only properties with a straight rear wall that are eligable to apply for full width extensions, even where the existing projection is small, say 300mm to 600mm ??????????

Is this just daft, or am I missing something.

Could one make the wall straight to claim the PD ? ie demolish projections, where does planning law stand on that ? the PD Technical Guidance p19-28 sais nothing on this.
I note that you partly demolish a roof, where a full hip to gable under PD is built, although that PD is concerned more with Existing 'Volume' and Chimney Stacks and Finished Roof line.
Does the PD Right to extend the rear GF concern itself with whether the projection is existing or additional - I interpret things to say it does not, and any projection puts a stopper on a full width PD right.

Some detail:

I wish to add a 6mt full width extension on a 1930's semi, its original width is approx. 6mt, no additional extensions have been added at the rear.

I have successfully applied, had approaved and built a 6mt full width GF exteniosn on another property, the rear wall was straight.

On the current property a 600mm D (x 2400mm W) projection exists - which allows for a marginal increase to the kitchen area.

After reading through the following threads:

It appears 'any' projection out from the rear wall brings rise to a PN Refusal on any rear extension with reasons:

- the enlarged part of the dwellinghouse would extend beyond a wall forming a side elevation of the original dwellinghouse, and would –
- have a width greater than half the width of the original dwellinghouse

And indeed in the street, a number of identical 6mt full width extension applications have been refused, it appears a number though resubmitting PNs or full plans and gaining permission for 3.5 - 5.0 mt extensions.
All properties in the street have the 600x2400 extension to the kitchen (built with the original building, the properties all being identical), I have noted some applications omitting this 'projection' on the drawings, yet the Officers refuse and quote the above text, do officers visit the property prior to a PN application to check what is drawn is what exists ?

Here are some pictures to explain what I think I understand, might be allowed if no objections were made:


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With a planning application there is some leeway on what can be allowed. This does not apply with PD - it either complies or not and there is no scope for loosening the rules.

The rules are simple; you can extend; from the originally built wall, or, if the house was built before October 1948, whatever sat on the ground in 1948 - that would include an extension built in September 1948.
Why not just submit your plans for approval? Not permitted development but it removes ambiguity
Thanks, so one could not make the wall straight ?? by demolishing the 600mm projection and making good before making a PN app..

Does this nonsense with the back wall and any projections excluding full widths, also apply to 3mt extensions ? or is it just Prior Notification Larger Home Extns (ie 3-6mts)

2x 6mt Larger Home Extensions in the road were first both 'Prior Approval Required and Refused', then resubmitted and reduced to 5mt and subsequently 'Prior Approval Required and Approved'and the other 'Prior Approval not Required', these are from 2013/2014, there have been no other Apps immediately near since.
My attached neighbour will strongly object, I understand the Overbearing and Impact will then be assessed, is it assessed on different criteria to that of a Full Planning App ??

Would it help if a 3mt extension PD LDC running along the Party Line was submitted, that would at least establish that majority of the Visual Impact would be there regardless, and the extra 2/3mts on the end would have less impact as it is further away from the back wall windows/view.

I understand I can put in a Pre-App on a Prior Notification, so at least I would get back some feedback from Officers before the actual process started and could avoid unecessary delays with re-submitted Apps.
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Your best bet at this point would probably be to just call the planning dept and ask your questions
I understand I can put in a Pre-App on a Prior Notification, so at least I would get back some feedback from Officers before the actual process started and could avoid unnecessary delays with re-submitted Apps.
No, pre-apps are seldom worth doing for domestic extensions, if anything they give the planners even more ammunition if they are minded to not approve your planning application if they have already said in a pre-app they won't approve it. Better to just submit exactly what you want and then negotiate after the application is in.
freddie is 100% right on pre-apps. Waste of time. Planners can be quite negative and once they decide on something - or partially decide - getting them to change their minds is very hard work. I always reckon a full application with all the information well presented is the best option.
Where any projection exists rearward, are even 3mt full width extensions unavailable to be claimed under PD, and would be refused as:

- the enlarged part of the dwellinghouse would extend beyond a wall forming a side elevation of the original dwellinghouse, and would –
- have a width greater than half the width of the original dwellinghouse

Interesting points raised above, with the latest extension built in the street (2019), 3x Apps were submitted as Larger Home Extensions Prior Notification PDs ... and each was repeatedly refused, 6mt then 5mt then 4mt all refused... then 2 further Full Plans Apps were then submitted, both for 5.00mt - but both were withdrawn, and finally a Full Plans Approved - but only for 3.5mt, will our LPA have a policy on extensions that dicatates the max depth under a Full Plans ?? I have seen a few under Full Plans only acheive 3.5mt, which is not what I want.

I take the points raised above, but if the depth is restricted by Policy, then would a 6mt App, refused but then resubmitted for less, ie 5mt - be a better option ?
Could one split the depth in half (see below) and have the side for the objecting neighbours depth reduced (on a second app), to help mitigate any visual or overbearing impact. The other sides exposure to impact would be lessened as there exists a 2.4 mt gap between properties and some outbuildings already in place along the perimeter.


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I read a case where a 6m Prior Notification was approved on appeal with the inspector seeming giving a lot of weight to the fact that a 3m PD with very high eaves right on the boundary would have had a very similar impact - in that case clearly breaching the 45 degree rule. I don't recall whether an LDC for 3m was presented with the appeal or whether just the possibility of it was considered. A moot point in your case due to your step, which only applies for the 3m PD in as far as any extension would have to step in turn.

I have a flat rear elevation but my 6m PN was turned down due to my neighbour objecting. However, I subsequently got planning permission for this 5.5m deep monstrosity! Note the low eaves and the step in on the neighbours side.

'Monstrosity' is rather apt. If I was the neighbour (to the left) I'd have preferred it without the step, at least he eaves would have been lower.
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@frank999 Look on your Local Authority's website for the 'Local Plan' this dictates the development policies that your local authority will take into account when they decide an application, they can vary greatly from one local authority to another, some may only have a few paragraphs regarding domestic extension, others will ave pages and pages.

cdbe ... matching materials, matching roof pitch and finish, windows in proportion, I think it looks good, nice job ... in comparison some of the c**p round here, built by people who don't care how it looks, its just the rental they are after, so lurking behind the 'street scene' nastyness polutes the visual amenity..

So what we see on your extn. (presume it was just the Ground floor that was added) was pbtained under full plans, how deep is the step in, and did the council request you do that. I like the pitched roof, looks good, was that personal choice or did planning officers advise you do it ... I am concerned my council might view such a pitched roof as adding to any 'overbearing' impact.

freddiemercurystwin ... thanks, I found a 'Design guidance' document from our local council that states:
The depth of a single storey rear extension, normally considered acceptable for semi-detached properties is 3.5 metres

So in the street, there are two houses with rear extens for 5mt approved under PN PD, one with one objection, one with no objections, but one house, where they refused a number of PN PD apps without any objections being raised - but only allowed a 3.5mt under Full Plans, these houses are just a few numbers away from each other, gardens are all the same size ... I will knock on the neighbours door with the 3.5mt, I know him, and see why the council gave him such a hard time - I note though that the first round of plans looked like they had been drawn by a novice.

I guess one approach is to try go the PN PD route, and if they refuse have a conversation with the officer and see what he thinks, and take it from there ... I was hoping this would be one app and done, but by the looks of things it could be a bit drawn out, but if I have to be patient so be it.

PS how do you quote just a posters name ??
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Just been round and seen the neighbour, it was the 600mm that the Officer wouldn't let go of, and forced the Full Plans App, which only gave 3.5mt, with the flank also required to beindented at an angle, so it was narrower at the end.

2x doors up though we have the 5mt's granted under PN PD's, I said to my neighbour, did you quiz the council on this, and they remained tight lipped.

Where would one stand with an appeal ... if you have an appeal case that argued that justy 600mm was not a side wall, which is what I have.

Has commented on 3 appeal cases:
There are several planning appeal cases on the Planning Jungle site on what constitutes a side wall. Three refer to single-storey side walls of depths varying from 0.55m to 1.2m, and determine that they do form a side facing wall; one appeal case states that a single storey extension projecting 0.6m does not constitute a side wall - so it's a moot point.

What a ridiculous situation, that such an insignificant projection can result in refusal ... I do not get the logic of such a restriction.

On a point raised earlier, about demolition, this case law appears to quash that thought:
In Arnold v Secretary of State for Communities and Local Government [2015] EWHC 1197 (Admin) (1st April 2015) that the demolition of an original elevation did not remove the relevant requirements of the General Permitted Development Order (2015) (as amended), and that for the purposes of calculating the limitations of permitted development, the starting point should be the location of the original wall, based on the original footprint of the house, whether the wall has been demolished or not.
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