My one storey extension is apparently a 2 storey extension

Regarding the first floor plan, are you saying no overhead view of the proposed extension is required at all?

The roof can be shown as a "roof plan" or just on your site plan. You would not show the first floor layout unless you are applying for work to the first floor.

I don't think a valley gutter will satisfy a planner in terms of separation. In this context it's visual separation of the two forms - the GF and first floor roofs, and whist a gutter is arguably a physical break, it does not break up the appearance, which is what planners are looking for.

So how would you suggest to satisfy this criteria and provide an adequate break?

If the rear extension roof is lowered and simply rests against the roof slope (and not the rear dormer) would that satisfy it being a separate?
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I would suggest you clarify with the planners what was wrong with it.

Or leave it as it is and apply for planning permission. As long as it satisfies your local planning policy.

Otherwise you are compromising a nice looking extension.

If need be, and if separation is the issue, leave the roof as it is and just hip it on the back down to a horizontal gutter. This design would look tacked on and would not likely be acceptable if planning permission was applied for, but could meet criteria for separation under the consultation process.
I don't think a valley gutter will satisfy a planner in terms of separation. In this context it's visual separation of the two forms.

where in the law does it discuss visual separation? The law is not concerned with such emotional trivialities beloved of planners..
I don't think a valley gutter will satisfy a planner in terms of separation. In this context it's visual separation of the two forms.

where in the law does it discuss visual separation? The law is not concerned with such emotional trivialities beloved of planners..

If you know anything at all about planning matters, then you will know that there is no such thing as "the law" when it comes to how design is interpreted.
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Reviving this thread.

Our draughtsman has suggested the below submission, so a flat roof design with no contact with the rear facade of the dormer


However i have a concern regarding eaves height. He has said in the draft application that he sent me that the document will be submitted with an eaves height of 2.962m (the top of the flat roof) instead of 2.55m (the underside of the soffit). The reason being is that per the PD technical guidance the top of a flat roof is considered the eaves (i have checked and the guidance confirmed it). I therefore think we are back to the same issue as before, ie the eaves of the extension will be considered higher than the existing eaves, even though visually the soffit is visually in line with the original building.

Anyone have any experience of flat roofs and PD and how the eaves will be interpreted.. Obviously from a visual and practical aspect if we have to reduce the ceiling height to accommodate the top of the flat roof as 2.55m it's going to be ridiculously low and look out of step with the eaves of the existing property.
You are still spending a inordinate amount of time, compromising design and the built extension trying to meet some unnecessary PD criteria when you could potentially get what you want via an application for planning permission.

The drawing looks incorrect as a flat roof never lines up with the soffits of a pitch roof. If it did, the flat roof fascia will be about 500mm deep if ceilings heights are kept the same, or the ceiling height will be about 2100mm if you have a fascia depth as drawn
Hi, no chance our council will approve under planning as we're a semi and proposing to go out 5metres. I've spoken to them and that's the line they gave me, ie 45degree trumps all.

Do we meet existing eaves with the above??? Bloody PD is so confusing. I think i need to spend a bit of money and get a proper planning consultant to look at it as our guy just isn't up to it.
I was confusing this post with another post on the neighbour notification scheme and yes it seems that the 45 degree rule would stump you.

Flat roof eaves is the top of the flat roof, and house eaves is the underside of the tiles - the soffits or fascias are not considered. So that new design fails on that. Your plan drawer should have known that if he was supposedly working on a PD compliant design.
You need to have lower eaves, and a part hipped roof as in the original design.

Have you actually engaged with the council regarding the reasons for the original refusal, and sought some guidance on what would be possible?
Thanks Woody, as I suspected then.

The council are notorious for being overworked, understaffed and inconsistent. I have asked for advice from them and they been vague. I'm going to change advisor as he's clearly crap.

Per the guidance the existing eaves would be 'the point where the extenal wall would meet (if projected upwards) the upper surface of the roof slope'. I think the top of the flat roof would only need to come down approximately 10 cm or so if we deemed the point below as the existing eaves.(Note snip below is from existing)

You could move that blue dot upwards to the top of the roof tiles as that is the point the eaves is deemed to be for this purpose IIRC.

Has your designer actually worked out the roof construction? That's a long span and it will probably need 220mm joists. With insulation and whether vented or not, then the roof could be quite deep. So if eaves (and ceiling) height is crucial, then you need to be certain that the roof can be built exactly as drawn.
Woody, just checked the guidance and yes you are correct, so yes slightly higher is allowed.

To be honest we've not even looked at the technical aspects re building yet, this whole process of applying and waiting is enough for now. I see little point in investing more cash on techinical drawings if we're not even sure we can get approval. But taken your points on board re the roof construction. With the large roof lantern I think that will open the room height up quite a bit, even if the rest of the ceiling is fairly low. Also, what the drawings show (which i haven't uploaded) is there is a step down to the extension floor as its a bit lower than rest of the house (not massively but enough to provide a bit more ceiling height).

Anyway, much appreciated on all your comments, been very useful.
Just thought I'd follow up on this. Approval obtained yesterday (well when I say approval I mean to say 'prior approval not required'). Had a nightmare with the council but in the end managed to get some subtlety amended drawings submitted and accepted with a small reduction of roof height without having to reapply. It came down to the wire though with our case officer changed 3 times during the 6 weeks, everyone seemingly on holiday at the same time and being passed back and forth between different people at the council.

Very happy! Now comes the really stressful bit, sourcing a reliable and high quality builder.
For the purposes of permitted development, if any proposed extension adjoins an existing structure which is also an addition (rather than being part of the original house), then the resultant combined additions must be considered; if that resultant combined addition does not comply with current legislation, then the proposed extension needs planning permission.

This is clarified by Government in their technical guidance; e.g. see pages 25/26 in relation to rear / side extensions. This confirms that if someone built a side extension, then as a separate operation wanted to build a rear extension which adjoins the side extension, for PD terms the council would have to considered the total resultant width.

I note you have now resolved the matter, well done!
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Now all you need to do is address that ridiculous pipe on the side elevation. Please tell me you are going to move the drain over so that pipe can come down vertically?

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