Permitted development, where is height measured from?

turkleton

Hi all,

I'm hoping someone can help answer a question as I can't find anything definite on the web and don't want to cause an issue for myself down the line.

The basic question is 'for permitted development where is the height measured from?'. For context I'm having a garden room built which is 2.5m tall so would fall under permitted development. The issue is that my garden has two levels, a lawn and then a concrete slab that has been there for at least 20 years and is a couple of inches higher. If we put the building on th slab would the 2.5 metres start at the concrete or the lawn?

Many thanks in advance. 

FaceHead

It's from the highest ground level that is immediately adjacent to the 'shed'.

You should be able to find the exact wording on the planning portal, but that is the essence of it.

In my interpretation of your post, the concrete slab is not part of the the shed, but part of the ground, so the measurement is from this (giving you the extra couple of inches in finished height). I'd say this view is supported by the slab having been part of the ground for so long.

What would a sensible person looking at the set up say is the ground level immediately adjacent to the new building? Photos would help, or just ask yourself honestly whether the slab is the ground. 

Bendy_House

Do you have reasonable evidence that the slab has been there for that amount of time?

Section62

turkleton said:

The basic question is 'for permitted development where is the height measured from?'. For context I'm having a garden room built which is 2.5m tall so would fall under permitted development. The issue is that my garden has two levels, a lawn and then a concrete slab that has been there for at least 20 years and is a couple of inches higher. If we put the building on th slab would the 2.5 metres start at the concrete or the lawn?

If you are that close to the limit that 2" (or whatever a 'couple' actually is) will make a difference - and you are concerned about future issues - then I'd suggest you look into making an application for the right kind of consent to avoid any doubt.  Assuming you are spending quite a bit on the garden room, the cost of getting consent is a trivial amount extra, and would eliminate the risk of expense if (between you and the builders) you inadvertently go over the limit and there is subsequent enforcement action taken against you.  Also consider whether by getting consent for a slightly higher building you would end up with a much better overall result.

The focus should always be on getting a good building, not on avoiding making an application for planning consent.