Single Storey Rear Extension on Sloping Ground

2 years ago

last modified: 2 years ago

Hi Everyone!

I have scoured this thread for answers to my planning query - which is around from which point we measure the eaves height for our proposed single-storey rear extension (Double pitch roof). Our property is located on flat ground, however the garden slope down! The ground slopes downward from the end of the patio to the end of the garden" as in the side view below.

Level A is same all around the house and level B is where my extension finishes in the garden(right-hand side). The proposed extension is shown by blue lines in the plan view below

The issue we are having is from where we can take our maximum 3m eaves measurement when planning the 6-meter extension - We hope for our application to fall under PD, however the planning dept. at the local council invalidated the drawings which sent in as the eaves height is too large. They seemed to completely overlook the sloping ground here?

I hope the diagrams I have included make sense If we took the eaves height to be 3m at the level B, that would give us a height of 2.5m at the start of the extension in that diagram.

Absolutely any help and guidance you could provide a noob in need would be much appreciated!

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Comments (2)

hedgehog99
2 years ago
My (limited, not professional) understanding is that the measurement is from level A. But you need professional advice on this: ask your architect (I hope you have one - building an extension on sloping ground like this is tricky and needs to be done right, both in terms of design and structural engingeering) and/or your local planning office for the definitive planning regulations relating to sloping ground.
Kam Sar thanked hedgehog99
PRO
Kay Moden
2 years ago
If you want to submit the application with the drawings above, I'm not sure this would do.

I'd recognise that it's not a common garden so it would require some proper drawings to explain the existing situation in relation to the new proposal (maybe you have some already), especially if you want to convince them it's PD. Also consider having a survey done to get the apropriate slope and height points.

A 6m extension is a relatively long one so it get's more sensible with the PD here, especialy in your case.

Consider a full application as well - the extra timing and cost may be worth the size of extension you want to achieve.

Another solution would be to drop the whole level with a few steps (if it's something you'd like). This will also help mititgate for the height at the end of the proposed extension.

Hope any of the above helps.
Kam Sar thanked Kay Moden
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Single Storey Rear Extension on Sloping Ground

Comments (2)

hedgehog99

Kay Moden

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