New Side Extension on Existing Side Extension PD?

[Blofeld72]

Hi there, a bit of a sanity check please.

I have a 1970s property that has an existing side extension as per the image below. (BTW the front is at the bottom and the rear is at the top)

I wish to build another side extension encompassing this existing one as per the image below.

It is my understanding that if I adhere to all of the Permitted development rules ie height less than 4m, less than 3m within 2m of the boundary, width less than half that of the existing house then this would be permitted development? (The house is not on any designated ground) there are no restrictions on the property. All other permitted development criteria would be met.

 

[tony1851]

That would be permitted development.

 

[Leofric]

It is my understanding that if I adhere to all of the Permitted development rules

then this would be permitted development

​

All other permitted development criteria would be met.

How could it not be permitted development in that case

 

[RichA]

Can you encompass -or- extend off an existing side extension. Or do you have to demolish; then build.

 

[tony1851]

Makes no difference in a case like this.