PD rules re: joining 2-storey extyension at roof

[RichA]

I am planing a 3 metre 2-storey rear extension within PD rules. I understand that no changes can be made to the existing toof. Does the image below look ok, particularly in reference to joining the new hipped roof to the gable end.

Black lines/white roof = existing. Yellow highlights/red lines show the new element.

 

[John D v2.0]

Can you do a full width extension under PD nowadays? I know you at least have to set in from the boundary on the second storey if you're close to next door.
Or is this a bungalow?

 

[tony1851]

That would be p.d., (assuming no nearer than 2m to either side boundary, and roof volume not increased by >50m³, and no nearer than 7m to rear boundary).

 

[RichA]

Apparently (according to planning consultant) the 50m³ doesn't apply if you are just joining a rear extension to existing

 

[Nakajo]

So when does it apply?

 

[RichA]

My thinking was that specific roof extensions (e.g. dormer were covered by Class B), but that roofing for Class A does not..

Looking at the guidance notes (p5) the following text does seem to cover it:

When considering whether a development proposal is permitted development, all of the relevant Parts of the rules and all the Classes within those Parts need to be taken into account. So whilst Part 1 Class A prevents the installation, alteration or replacement of a chimney, flue or soil and vent pipe from being permitted development, Class G includes such development as permitted development subject to the rules set out under that Class. Similarly, changes to the roof of a house are not permitted development under Class A, but may be permitted development under Class B or C. For example, where a proposed two storey extension at the rear of a house has a roof that joins onto the main roof of the original house, the works will need to meet the requirements of both Class A (which covers the enlargement of the house) and Class C (which covers any alterations to the roof) in order to be permitted development. If the works also include the creation of a dormer window to enlarge the roof space, either in the extension or the original roof space, then they would also need to meet the requirements of Class B.

i.e. Following the red/blue example from the guidance notes: I think my roof plan above complies with both Class A and Class C (and as I am not adding a dormer, does not need to comply with Part B).

 

[tony1851]

Yes, seems OK on reflection.

 

[RichA]

Fortunately the example they use is effectively an exact match for my scenario, as the guidance doesn't really make the general principle crystal clear.

I.e. The first example they use re: chimneys. In a 2-storey extension, does that mean one can alter/remove the chimney (Class G); or not (Class A)?

 

[RichA]

The Council have told me that they are going to deny my Class B exclusion.

"we have concluded that the assessment should include Class B. In order to facilitate the creation of the two storey rear extension a portion of the roof form would be altered and the ridge height of the property would be extended. We consider that the proposed extension does not simply join onto the main roof of the original house. As a result of the increase in volume of the additional roof space, the proposal would fail to comply with Class B. I would suggest that the best way to overcome this issue would be to set the proposed roof down below the ridge height of the lower side element."

Slightly disappointed by their view. The guidance doesn't say that the new roof has to simply join the old roof. It just says that it has to join it. Semantics 1, me 0.

On a separate note, if I revise the drawings (attached) can I submit as part of this CoL application? Or do I have to withdraw my application & resubmit (starting the 8 week clock again)?

 

[RichA]

The Council confirmed that I can't resubmit drawings for a CoL and and have rejected it on the grounds that they view this as an enlargement of the original roof rather than just the new roof joining the existing old roof (and have therefore also assessed it under Class B).