Define "Extention"

If its connected to the house but has no access to it, it's not an extension. It's not even a granny flat, as those still require access between the main house and the granny flat (and granny flats typically require planning permission).

An extension is extending the existing house, for the people living in that house, to give them a bigger house. What you're proposing is a new small house connected to an existing house (but no access between them and not for the occupants of the existing house). That's not an extension.

What you're proposing requires planning permission, and I would say is extremely unlikely to be granted.

I agree with Penn. But if you're willing to make an opening between the new construction and the existing house, it could be classed as an extension. There's have to be some redesign, since presumably you won't want passage between the existing house and the extension to be through the bathroom.

Note that the 40 sq m limit is inclusive of all extensions to the house constructed (with or without planning permission) since 1964. So if the house was previously extended by, say 25 sq m, the max you can do now would be only 15 sq m. Also note that any windows in your extension all have to be at least 1 metre from the boundaries of your property if it's to be exempt.

https://www.boards.ie/discussion/comment/120742783#Comment_120742783

What the OP is intending may require planning, but that has no bearing on whether something is or isn't an extension.

If its connected to the house but has no access to it, it's not an extension.

I understand the logic there. But I don't know if there is anything in planning law that supports that. I haven't specifically looked it up, but I can't recall a clear definition of extension in the Act or Regs. It just says "the construction or erection of an extension".

An extension is extending the existing house, for the people living in that house, to give them a bigger house.

I'd agree with that, more or less. Nothing in that says that there must be an internal connection.

As above, I understand where you are coming from. But it seems to the that the more obvious prerequisite is that it cannot be detached, and after that it's vague.

What you're proposing is a new small house connected to an existing house (but no access between them and not for the occupants of the existing house).

If the development is not for the occupants of the dwelling, it would require planning. That is entirely separate to the issue of whether it's an extension. An extension that requires planning as still extensions.

Similar to how if it were under 25sqm, it would be built as exempt development. But if not for the occupants it would require planning.

odyssey06

Also, it's not clear from your diagram how much remaining space will be left in your garden. You need to leave at least 25 square metres.

You cannot reduce the open private space, reserved exclusively for the use of the occupants of the house at the side or rear of the house below 25 square metres

https://mcmahonsolicitors.ie/3606-2/

https://www.boards.ie/discussion/comment/120745144#Comment_120745144

agreed

if the green in that diagram is the private amenity space, then its highly unlikely what they are doing can be considered "exempted development"

also note the amenity space must be "useable" and not haphazard or ancillary to pathways

kevgaa

If the new building in the garden is joined to the house but with no access is it not effectively the same as a Semi-detached joined but with no access so therefore it could be argued thats its a separate property?

https://www.boards.ie/discussion/comment/120745026#Comment_120745026

I agree in general, but as per kevgaa's point above, the thing that would distinguish whether what the OP is suggesting is an extension or not would come down to things like separate access, no access between units, separate facilities (like bathroom, kitchen etc).

What the OP is suggesting imo would at best be an attempt at a granny flat (though even those require a door between the existing house and new build so the flat could be converted into liveable space for the occupants of the main house after it's no longer required to serve as a granny flat.

What the OP is proposing imo, is a new dwelling, similar to just building a new house onto the side of an existing so you have two semi-detached units.

With regards the planning law, I would take the definition of how the floor area of the original house may not be increased by more than 40m2 (for an extension to be exempt) to mean the 40m2 must be part of the actual house. Something external would fall more under sheds. Though the 25m2 also can't be lived in. I'm guessing there may be a definition somewhere though not sure where it is myself. I really doubt any planner or enforcement officer would determine what the OP is proposing to be an extension though.

muffler

I dont think that the term "extension" needs to be defined in planning legislation at all as its pretty obvious what the word means in every day language. The Cambridge Dictionary defines the word as "the fact of reaching, stretching or continuing; the act of adding to something in order to make it bigger or longer"

https://www.boards.ie/discussion/comment/120745144#Comment_120745144

Correct, there are a number of planning requirements to qualify as exempt development. Private open space, height, distance from boundaries, windows.

Those are not up for debate at all, but do not affect the definition of "extension".

https://www.boards.ie/discussion/comment/120745557#Comment_120745557

No, that argument as no validity at all. The property is the curtilage and/or the title deed. A shed at the back of the garden is detached, it still part of the same property. An addition as described in the OP is the same property, regardless of whether or nots it's an extension.

https://www.boards.ie/discussion/comment/120746420#Comment_120746420

As above, being an extension and being the same of separate properties are not related. (an extension that projects onto another property is still an extension, albeit not permitted).

And I agree that the OP does appear to be trying to utilise a loophole to build a small flat as exempt development. We all agree that it not inline with the spirit of the exemptions. And I doubt they would successfully be granted a Section 5 declaration. But, nevertheless, I honestly don't think there is anything in law that confirms those views. Should be easy to point out where it is if it does exist. It's a big Act, and I'm not saying I have it memorised.

https://www.boards.ie/discussion/comment/120746475#Comment_120746475

And in the absence of a definition in the act, it would default to common language. And the common language above does not distinguish between the internal connected space, and the external mass.

Forgetting about extensions for a minute. There is not requirement for all rooms in a house to be internally connected. If a house has a small room that had its only external access (say an outhouse or laundry) but was fully within the mass and footprint of the house. The room not would be considered a separate unit or anything other than part of the house as a hole.

Given how prescriptive schedule 2 is. I'm surprised the need for a connection is not listed.

I think it does matter whether the construction is an "extension" or not. By default, all developments require planning permission unless they fall into one of the categories of "exempted development" set out in the legislation. There are many such categories, but I think the relevant one in this case is Class 1:

"The extension of a house, by the construction or erection of an extension (including a conservatory) to the rear of the house or by the conversion for use as part of the house of any garage, store, shed or other similar structure attached to the rear or to the side of the house."

This is an exempted development, provided certain conditions regarding the area, the height, the amount of open space remaining, etc, are met.

The word "extension" isn't defined in the legislation, so it has its ordinary meaning. But note the word actually appears twice. First, you have to be extending a house. Secondly, you do this by the erection of a physical extension (or by converting an existing structure that is already attached to the house, but that's not relevant in this case).

"House" is defined in the legislation; it's a building or part of a building occupied as a dwelling. In some contexts in the planning legislation "house" can include a building that has two or more dwelling it it, but not in this context.

To extend the house, as opposed to extending the building, you have to extend the part of the building occupied as a dwelling. If what you want is an annex to be occupied as a separate dwelling, that's not an exempt development.

Still, thinking about the matter, I don't think this absolutely requires an entrance between the old part of the house and the new. It's clear that adding a conservatory can be an extension, even though a conservatory abutting a house might only have an entrance from the garden. But whatever you're building does have to be for use as part of a the existing dwelling, which is going to be a lot easier if there is a connecting door. A conservatory that opens only to the exterior is one thing; an assemblage of bedrooms, livingrooms, bathrooms, etc that opens only to the exterior is quite another. The absence of a connecting door does suggest that this may not be an extension of the house, but rather the provision of a second house in the extended building.

I can see why the planning authority were reluctant to commit.

So we come now to the elephant in the room; the question we have all been studiously avoiding.

OP, why are you constructing an extension with no connecting door to the rest of the house?

https://www.boards.ie/discussion/comment/120747442#Comment_120747442

The entire issue hinges on whether it's an extension or not, and that alone imo. If a attached but unconnected development is an extension, then it can potentially be built as exempt development (subject to meeting other requirements). If it is not an extension, it cannot be. It's really straight forward.

Correct, it has to be a single dwelling house and not apartments, flats, townhouse or anything that might generally be referred to as a "house".

And, even more importantly, the language in schedule two confirms that a conservatory is type of extension and not just something additional permitted under class one.

But whatever you're building does have to be for use as part of a the existing dwelling, which is going to be a lot easier if there is a connecting door. A conservatory that opens only to the exterior is one thing; an assemblage of bedrooms, livingrooms, bathrooms, etc that opens only to the exterior is quite another. The absence of a connecting door does suggest that this may not be an extension of the house, but rather the provision of a second house in the extended building.

Many aspect of planning deal with use and not form. A development attached designed to be used as a separate accommodation (like a granny flat) is not permitted under exempt development regardless of whether it is connected or not. (doors can be locked and render inoperable very easily.

OP, why are you constructing an extension with no connecting door to the rest of the house?

I think we know exactly why they are doing it. The actual answer for what OP is intending to do was provided by @Penn in post #2 (for the people living in that house).

The rest of the thread is somewhat academic discussion about an unexpected omission from the regulations.

Mmm. This annex could be intended to be used as something like a parent's retreat, or a teenagers' retreat, with the entire property still being occupied and used by a single family. Maybe shared facilities will include not only [what remains of] the garden but also parts of the existing building — e.g. a laundry, a garage, possibly even the kitchen. (We're not told if a kitchen is to be installed in the annex.) I suspect questions like this will arise more and more with the phenomenon of adult children remaining at home for prolonged periods.

But the absence of a connecting door means that it's apt for use as a self-contained dwelling even if that's not the immediate intention. The main room in the annex clearly could accommodate a kitchenette.

Maybe the question comes down to this; can this structure be an extension to a house if, in order to get into it, you have to leave the house, pass through open space, and only then enter the new structure?

I'd be tempted to say "no", but of course the definition explicitly includes a conservatory as an extension, and that may be exactly how you get into a conservatory.

But perhaps the answer is this: the express inclusion of a conservatory operates to extend the definition. An extension to a house ordinarily has to be capable of being entered directly from inside the house; it has to result in expanded interior spaces, not two separate interior spaces. A conservatory opening only to the garden would not be an extension but for the fact that it is expressly included. And therefore annexed structures which have no direct access from the rest of the house and which are not conservatories are not included.

It's an argument. But we can't know which way a court would rule on this question of interpretation unless the matter is actually taken to court. And of course the likely circumstance in which this would end up in court is if enforcement action is taken, and that's most likely to happen if the annex is in fact being used as a separate self-contained dwelling, in which case permission is definitely required and the case could be determined without the court taking any position on the interpretation of "extension" as used in Class 1.

So the point may remain one for academic discussion.

If there is no connection then the floor area of the house has not been made bigger therefore it is not an extension.

It then becomes class 2 development, which has a over footprint restriction of 25sq m.

In any communications I've ever had with local authorities about this type of development, there always has had to be a connection between the new and old in order to argue is existence as an "extension"

If it's not connected, it's not "extending" anything

I think you mean class 3? Class 2 is heating and power infrastructure —chimneys, boilerhouses, fuel tanks, wind turbines, solar panel arrays and the like.

Class 3 is greenhouses, stores, sheds and the like within the curtilage of a house. It's correct that there's a 25 sq m limit, but there's also a condition that the structure not be used for human habitation, which this one will clearly fail.

Yes I mean class 3, thanks. I always forget about that little class two being squeezed in between the other two big ones.

And yes it would fail also on the habitation point.

https://www.boards.ie/discussion/2058301759/define-extention

Yeah I think an externally accessed conservatory or utility room, there could be justification as to why they might constitute an extension, as their use is clearly linked to the amenities of the house, by the occupants of the house. You could potentially justify that as an extension without an internal link, but equally that could constitute a Class 3 as its unlikely to be more than 25m2 regardless.

A new structure, connected to but with no internal links between, which provides amenities such as a bathroom, bed space, cooking facilities, living space, it's own external access.... that's clearly by its design not something intended for use as part of the main house and instead can operate independently of the main house (depending on services, heating etc).

I always come back to the provisions regarding family (granny) flats. They require an internal door or link between the units, so as when the family flat is no longer required (R.I.P Granny), the flat can be converted into use by the occupants of the main house. There are other regular conditions imposed, such as having to prove every few years that the family flat is still required for the family member, and that you cannot rent it out to other persons.

So I would say the main provisions for what constitutes an extension would be a physical link, shared floor area, and the intended use. Though perhaps the reason why there isn't a proper definition is because as we've all proven, there are always exceptions and caveats to the rules.

The Continental Op

I'd also question if this amounts to an extension due to the nature of the materials that are used in a cabin?

Gumbo

What you describe and demonstrate is not planning exempt.

https://www.boards.ie/discussion/comment/120747816#Comment_120747816

The OP tells us nothing about the materials he intends to use. I wouldn't draw any inferences about the materials from the use of the word "cabin".

In any event, it doesn't matter. The regulations on what constitutes a class 1 exempted development say nothing about the materials used. This is in marked distinction to some of the other classes of exempted development; e.g. class 5 (gates, fences and walls) exempts gates etc (on certain conditions) if constructed of specified materials (brick, stone, wood, etc) but not otherwise. It follows that whether a structure is an exempt class 1 development won't depend on what it is made of; if it did, the regulations would say so.

The Continental Op

https://www.boards.ie/discussion/comment/120747843#Comment_120747843

So you can build an exempt extension and build it without any regard for building regulations?

https://www.boards.ie/discussion/comment/120748202#Comment_120748202

theres no overlap between planning exempted development and building regulations.

you are required to build to building regs even if the development is exempt.

The Continental Op

https://www.boards.ie/discussion/comment/120748237#Comment_120748237

Thats my point I draw the inference from the OP's posting "We are planning to put a cabin in out back garden" that they are going to buy a cabin and put it in the garden because they used the word put rather than build. Might just be OP's use of language?

https://www.boards.ie/discussion/comment/120748321#Comment_120748321

I also inferred from the OP that it would be a prefabricated structure or one assembled on-site, though that doesn't necessarily mean it's non-compliant with building regulations.

https://www.boards.ie/discussion/comment/120748321#Comment_120748321

well compliance with building regs actually takes in more than just the construction of the development itself. for example, access for fire fighting is a building regulation, and there's no indication either in any post if that is being complied with... and a major point in why these kind of developments are completely unwanted by planning authorities.

but hey, if they are trying to subvert planning regs, it isnt a long stretch to conclude that they will subvert building regs as well.

The OP doesn't ask about building regulations. Obviously, exempt or not, the structure must comply with building regulations. Presumably the OP is satisfied that it will; otherwise he would be asking about that too.

But, yeah, syd has a point: if there's no access to the annex from inside that house, and if it's used for human habitation, then SFAIK building regulations will require it to be accessible to a fire tender. Maybe it is, from the side or back of the garden?

https://www.boards.ie/discussion/comment/120747460#Comment_120747460

An annex, whether attached or not, can be used as part of the house. But under class 3 it cannot be used for habitation. So study, games room, den, not bedrooms. OP hasn't specifically said bedroom (but I suspect). And the potential to be used as a separate dwelling does not affect the exemption. It's purely on the actual use.

So it still purely comes down to the meaning of extension. My feeling, based on conservatory, if that there is not legal requirement for an extension to be continuous - but that council and ABP would likely side with the intent of the regs and not a legal interpretation.

https://www.boards.ie/discussion/comment/120747808#Comment_120747808

As above, having the capability to be used by a external user doesn't affect exemption. It's purely the actual use. Like the way a teenage retreat can be exempt as class 3, even though it has the potential to be a detached bedroom. Exemption only ceases applying if it becomes used for habitation.

The granny flat connection condition is common practice, but I don't believe it is mandated.

https://www.boards.ie/discussion/comment/120747816#Comment_120747816

Not related to planning for class 1 (extensions). It is for class 3 (external finishes only).

https://www.boards.ie/discussion/comment/120748202#Comment_120748202

You have to comply with building regulations. That is not a matter related to planning. There is no reason why a prefab structure cannot comply with building regs. Being "put" in the garden is not proof of anything.

The class 1 exemption covers the construction or erection of an extension to a house, so it's very much an exemption for works, rather than use. (Same is true for the class 3 exemption.)

The extension has to be an extension to a house; it's not enough that it extends the building. So the mere fact that the new building is physically connected to the existing building doesn't bring you within class 1; the design of the new building must be such that it extends the house — the area occupied as a dwelling. If the new construction has its own facilities for habitation, and you can only pass between the old and the new constructions by going through the garden, this looks a lot more like a separate dwelling than an extension to the existing dwelling; it doesn't come within Class 1 simply because the new building abuts the old building. Nor does it come within Class 1 because the new building is, in fact, used as supplementary residential space by the occupants of the existing building; Class 1 looks at the construction and characteristics of the new building, but not at the actual use made of it.

There's no express requirement that the interior space of the new building should directly connect with the interior space of the existing building, but I think there's a strong argument that it's implicitly required, or at least the lack of such a connection will generally suggest that this is not an extension to a house. Conservatories are expressly included in Class 1 by way of an exception to, or override of, the expectation of an interior connection.