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Caravan Act, PD & Full Planning Explained

Granny Annexe Planning Permission in
Perth

Whether your Perth annexe needs full planning permission depends on how it’s built and how it’s genuinely used, mobile and ancillary can mean a much simpler route than permanent and self-contained. We check this properly from the outset.

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Local to Perth
Three Routes Explained
Council-Ready Applications

Granny Annexe Planning Permission In Perth, Explained Properly

Perth homeowners considering a granny annexe need to understand what actually changes the planning position, self-containment. An outbuilding used incidentally, for storage, a home office, or a hobby room, can be permitted development in Perth, subject to height and coverage conditions.

Introduce a genuine bedroom, bathroom, and kitchen used independently of the main house, and that outbuilding stops being incidental, taking it outside permitted development regardless of size.

A mobile structure meeting the Caravan Sites Act 1968 definition offers a third route for Perth annexes, but only where it genuinely remains ancillary to the household, not a separate residence in its own right. A Perth annexe needing full planning permission usually needs both, our Building Regulations drawings in Perth service covers the technical compliance side, and our structural calculations in Perth service covers the engineering detail.

Right Route Confirmed

Caravan Act, permitted development, or full planning

Caravan Act Route

Movable structures that may need no permission at all

PD Size & Siting

Permitted development limits checked properly

Council-Ready

Applications built to be approved

Granny annexe planning permission

How We Help in Perth

We start every Perth annexe project by establishing the real starting point, a mobile structure within Caravan Act limits, an incidental outbuilding, or genuine independent living space, since that single distinction shapes everything that follows.

Your Perth application or certificate, whichever applies, is built around what your local council specifically expects to see, not a generic template.

Structural and building regulations work for Perth annexe projects is handled properly from the outset, informed by real experience with this kind of project.

Perth Granny Annexe Projects Done Properly

We treat every Perth annexe project as needing a genuinely honest assessment first, not a sales pitch toward the most expensive route.

Real experience with the Caravan Act, permitted development, and full application routes is what we bring to every Perth project, not a one-size answer.

Structural and building regulations detail for Perth annexes are handled properly from the outset, whichever route your project actually takes. If you need help with a granny annexe, give us a call on 0330 133 5316 or fill in the form below.

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Perth Annexe Planning Questions Answered

What determines if my Perth annexe needs planning permission?

This genuinely depends on your specific plans for Perth, we check whether the structure is mobile, incidental, or self-contained before advising either way.

What size limits apply to a caravan-style annexe in Perth?

The Caravan Sites Act 1968 sets the limits, 20 metres long, 6.8 metres wide, 3.05 metres internal height, and the structure must be moveable by road in one or two sections, we check whether your Perth plans genuinely meet this.

What outbuilding rules apply to a Perth annexe?

It depends on genuine use, an incidental Perth outbuilding can qualify under Class E, but introducing real sleeping accommodation used independently takes it outside permitted development regardless of size.

What makes an annexe a separate dwelling in Perth?

Genuine independence is the test in Perth, if the annexe could function as a separate home on its own, full planning permission is almost always the realistic route.

Is a Lawful Development Certificate worth it in Perth?

Strongly recommended for Perth annexes, an assumption that a structure qualifies isn’t the same as formal confirmation, and a Lawful Development Certificate closes that gap.

Can you manage everything for my Perth annexe project?

Yes, we coordinate every part of a Perth annexe project, from establishing the correct route through to building regulations sign-off, so nothing falls through the gap.