Conservatory or Extension

Runningfast

Does anyone know the planning/building control description of when a conservatory becomes an extension? I have read the https://www.planningportal.co.uk and can not found the answer.

Size wise I am talking permitted development i.e. 3m addition to the back of house and maximum 4m high from natural ground level (attached house).

For discussion purposes there is an external quality door and wall separating the original house from the new addition.

Reason:

I'm thinking about adding a new addition to the house and want to stay away from the planning process or having to undertake the neighbour consultation process so looking to build in accordance with permitted development.

Just need to decide if an extension or conservatory would best suit my needs and trying to find the legal description for the differences. I understand that I would require building control approval for certain aspects for example if I decided to knock through the external wall or extend the current heating system in to the new addition etc etc.

Reading some websites some say the difference is based on glazing area, others say must have a glazed roof others say can have a solid roof as long as 80% of walls are glazed others say putting roof windows in to a solid roof classes as a conservatory etc. Anyone know the actual legal description in planning terms?

Thanks

Doozergirl

There are building regulations for depth of foundations, thermal efficiency of floors, walls and ceilings, weather proffing, heating etc to meet regs.

You either meet them or you don't. If you don't, that external door is there to qualify whatever substandard erection you put on as an 'outbuilding'.

Harsh, but true.

Runningfast

Thanks for the reply. I understand that hence why I mentioned from a discussion point of view the external doors and also building regs for certain aspects.

I am trying to clarify the definition. I.e. you have 2 structures what defines one as a conservatory the other an extension.

I am trying to work out what is best for my needs but will be built under permitted development rights from a planning perspective and applying for building regs as and where I need them etc.

Davesnave

As Doozer says, what seems to define something as a conservatory or an extension, is whether it has that piece of paper saying it meets current standards for building and thermal efficiency. Either it does or it doesn't, and if it's not inspected as it's being built, it won't.

Do you know what type of structure you prefer and what you want from it? Once you do, it's possible, if not especially easy, for the uninitiated to do the maths, just as I did when converting a garage to habitable space. The inspection of this was pretty cursory, but I took many photographs to show the insulation work in progress etc. It's now officially an extension of the bungalow.

OTOH, at the back of my property I'm currently engaged in replacing a "substandard erection" (well, what else would anyone expect at my age?;)) with another, much less 'substandard' conservatory. I know it's a conservatory, though, because it won't meet thermal efficiency requirements, having a glass roof of a particular type and less insulation in the walls and floors than is ideal. No one is inspecting the foundations either, although they closely match those of the main property. It's also under 30m2....just about!

But the point is, I know what I want. For 3 months I had scaffolding over that area and the loss of light made the rest of my living space depressing. Fixing the light issue could be done at a cost, but I'm not interested in investing that amount, so the external doors will stay and the heating won't be extended.....well, not until the rest of my works are signed-off anyway!

If you can get enough light into other parts of your property without major surgery, I'd say go with a 'proper' extension within permitted development limits for size and get it inspected and signed-off. It will always add more value than a conservatory and have a greater range of uses.

Millions live in poorly lit houses in this country, with it's dull, miserable winter weather and don't seem to notice, so for you, maybe the light issue won't be a deciding factor anyway.

teneighty

As far as Building Regulations are concerned it is a bit of a minefield. They changed the rules a few years back and the old nice clear definition was 75% glazing to walls and 50% glazing to roof. The new rules have no definition other than those you already quoted, so some Councils are still using the old glazing limits and some don't insist on any glazing. It is crazy.

Probably best to ask your local Council Building Control Department what interpretation of the rules they apply.