Flat roof permitted development

[Foot]

Hi

I'm wondering if a flat roof extension to a pitched roof bungalow is permitted development

the depth of the extension would be 3m and the height would not exceed 3m

my slight concern would be about matching materials as the existing pitch roof is concrete tiles and the flat roof would be a single ply membrane

 

[tony1851]

IIRC the eaves should be the same height as the existing eaves to qualify as p.d., which might make the extension a little low internally.

 

[Foot]

Thanks, the eaves height has also crossed my mind as initially I thought this might be an issue as it appears tight

I've had a quick read of this which makes me feel more comfortable

(d) the height of the eaves of the part of the dwellinghouse enlarged, improved or altered would exceed the height of the eaves of the existing dwellinghouse

For the purpose of measuring height, the eaves of a house are the point where the lowest point of a roof slope, or a flat roof, meets the outside wall. The height of the eaves will be measured from the ground level at the base of the external wall of the extension to the point where the external wall would meet (if projected upwards) the upper surface of the roof slope. Parapet walls and overhanging parts of eaves should not be included in any calculation of eaves height.​

My thinking is this.........

So the height of my flat roof extension EAVES cannot exceed the height of the eaves of the existing dwellinghouse.

The height of the existing eaves is the point where the outside wall intersects with the roof slope (measured to top surface of tile)

Equally the height of the flat roof eaves is the point where the lowest point of the flat roof meets the outside wall (so I understand this to be the underside of the flat roof joists)

By this reckoning I do not see that the height above the eaves is considered providing the overall height does not exceed 3m.......so the depth of the flat roof joists and warm deck insulation would not be the included in the eaves measurement

 

[Foot]

Hmmm.....now i've scrolled down a bit the technical guide shows a diagram to the top of the flat roof covering

 

[Foot]

Ive had a further thought on the height of my eaves scenario

I am thinking of adding a dummy pitch roof around my flat roof which could lower the external eaves to match my existing eaves

 

[Markiv]

Ive had a further thought on the height of my eaves scenario

I am thinking of adding a dummy pitch roof around my flat roof which could lower the external eaves to match my existing eaves

Please could I ask if this worked for you?

thanks