Granny Annexe Planning Permission in Cambridge

Granny Annexe Planning Permission in
Cambridge

A granny annexe used purely as extra living space for the same household in Cambridge is treated differently to one with its own separate facilities used independently. We establish which describes your actual plans before advising anything.

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Granny Annexe Planning Explained For Cambridge

Cambridge families often assume a granny annexe is either always simple or always complicated, the reality depends entirely on how it’s built and used. The Caravan Sites Act 1968 defines a caravan as a structure capable of being moved by road, within strict size limits, and a genuinely mobile annexe meeting that definition can sometimes avoid planning permission altogether.

Permitted development under Class E covers incidental outbuildings in Cambridge, subject to height and coverage limits, but not genuine self-contained living accommodation with its own bedroom, bathroom, and kitchen used independently.

We assess your specific Cambridge property and plans against all three routes honestly, rather than assuming the most complex one applies by default. A Cambridge annexe needing full planning permission usually needs both, our Building Regulations drawings in Cambridge service covers the technical compliance side, and our structural calculations in Cambridge 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

How We Help in Cambridge

Every Cambridge annexe enquiry starts with establishing the real facts, is the structure genuinely mobile within Caravan Act limits, is it staying incidental to the house, or is it a self-contained dwelling, since that shapes the whole route.

From there, we prepare exactly what your Cambridge project needs, whether that’s a Lawful Development Certificate confirming caravan or permitted development status, or a full planning application.

Structural and building regulations input runs alongside the planning process for Cambridge annexe projects, whichever route applies.

Getting The Route Right For Your Cambridge Annexe

Every Cambridge annexe assessment starts with an honest read on which of the three routes genuinely applies, not an assumption that defaults to the more complex, more expensive option.

We check the real mobility and size of a proposed Cambridge structure against the Caravan Act’s actual legal definition, rather than assuming it qualifies.

Where a Cambridge annexe genuinely needs a full application, we say so directly and build it around what the council expects to see. 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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Granny Annexe Planning Permission FAQs for Cambridge

Do I need planning permission for a granny annexe in Cambridge?

It depends on three things, whether the structure genuinely qualifies as a caravan under the Caravan Sites Act, whether it stays incidental to the house under permitted development, or whether it’s a self-contained dwelling, which almost always needs a full application in Cambridge.

What is the Caravan Act route for a Cambridge annexe?

Under the Caravan Sites Act 1968, a structure qualifies as a caravan if it’s capable of being moved by road in no more than two sections, and doesn’t exceed 20 metres in length, 6.8 metres in width, or 3.05 metres in internal height, Cambridge annexes meeting this can often avoid planning permission if they stay ancillary to the house.

Can I use permitted development for a Cambridge annexe?

Only if it stays genuinely incidental to the house, Cambridge outbuildings under Class E permitted development cannot be separate, self-contained living accommodation, the moment sleeping facilities are used independently, permitted development stops applying.

What counts as a self-contained annexe in Cambridge?

A Cambridge annexe with its own bedroom, bathroom, and kitchen, used independently of the main house rather than as shared accommodation, is generally treated as self-contained, which usually means full planning permission is needed.

Do I need a Lawful Development Certificate for my Cambridge annexe?

We recommend it, even where your Cambridge annexe genuinely qualifies as a caravan or permitted development, a Lawful Development Certificate gives you written confirmation rather than an assumption that could cause problems later, particularly when selling.

Can you handle planning and building regulations for my Cambridge annexe?

Yes, we handle the full picture for Cambridge annexe projects, the planning route, whichever applies, and building regulations compliance, as one coordinated service.