Documents for an annexe for a dependent relative

An annexe for a dependent relative is normally applied for as a householder planning application, and the decisive question is whether the accommodation remains ancillary to the main house or amounts to a separate dwelling. That turns on physical and functional links: shared access, a shared garden, no separate boundary, shared services, and living arrangements that stay connected to the main household. Get the drawings right and the application is usually straightforward. Draw a self contained cottage with its own gate and the council will refuse it, or grant it as a new dwelling with all the policy tests that brings.

Families often describe the proposal as giving a relative independence. That is the opposite of what the application needs to show.

Ancillary use against a separate planning unit

Planning law looks at the planning unit: whether the site continues to function as one residential unit or whether a new, separate one has been created. Courts have considered the physical layout, the way the land is used and the degree of separation between parts of it.

The features that point to a separate dwelling:

• A separate vehicular access or a dedicated parking area divided from the main house.
• A fenced or walled garden serving the annexe alone.
• Separate utility meters, a separate postal address or a separate council tax entry treated as independent.
• A layout with no internal or covered connection to the main house, sited at a distance from it.
• A scale and specification that reads as a house rather than as accommodation attached to one.

The features that point to ancillary use are the mirror image: a shared drive, an open shared garden, shared services, an internal door or a short covered link, and a modest scale.

A kitchen is not decisive on its own. Officers know that a dependent relative may need to make a meal, and a kitchenette in an annexe does not by itself create a dwelling. The combination of features is what matters.

Evidence of dependency and shared living

The planning system is assessing the use of land rather than the family's circumstances, so keep this proportionate. A short covering statement should explain who the annexe is for, the nature of their dependency in general terms, and how daily life will be shared with the main household.

Do not submit medical records. A brief statement is enough, and personal information submitted with an application goes on the public register.

Where the council asks for more, it is usually seeking comfort on two points: that the arrangement is part of one household, and that it will remain so. The answer to the second is a condition, not a document.

Drawings the council needs

The drawing set does most of the persuading.

1. A location plan at 1:1250 with the site edged red, showing the whole property as one unit.
2. A block plan showing the annexe, the main house, the shared drive and the open garden between them.
3. Existing and proposed floor plans of both the annexe and the affected parts of the main house.
4. Existing and proposed elevations, with the annexe shown alongside the house for scale.
5. A drainage layout showing the connection to the existing system.

Show the connection. Where there is an internal door, a covered walkway or a shared hall, draw it and label it. Where the annexe is detached, keep the distance short, keep the garden open between them, and avoid drawing a boundary that splits the plot.

Councils return applications for a missing block plan more often than for anything else on a householder scheme.

The levy exemption for a residential annexe

The Community Infrastructure Levy Regulations 2010 provide an exemption for a residential annexe built within the curtilage of an existing dwelling, alongside the self-build exemption for a new home.

The procedure is unforgiving and it catches people every year.

• The exemption has to be claimed on the correct form and granted before development begins.
• A commencement notice has to be submitted before work starts.
• Starting work before the claim is granted, or without the commencement notice, can lose the exemption entirely.
• A clawback period applies, so disposing of the annexe separately within the stated period can make the levy payable.

Check the current forms and the procedural steps with the charging authority before you start, because the detail is procedural rather than discretionary and there is no appeal against missing a step.

Drainage, utilities and parking

For a modest annexe connected to the existing drainage, a short note and a layout drawing is usually enough. Where the property is on a private treatment system, the council will want confirmation that the system has capacity for the additional load, which may mean a note from the installer or an upgrade.

Parking is assessed against the council's own standards. An annexe rarely generates much, but the standards may still require a space, and drawing one as part of the existing driveway supports the ancillary argument better than a separate bay.

Utilities are worth a thought for a different reason. Separate metering is one of the factors that points towards a separate dwelling, so if there is no technical need for it, do not do it.

Conditions tying the annexe to the house

Expect a condition. The usual wording restricts occupation of the annexe to a person who is a member of the household of the main dwelling, or to someone dependent on that household, and prevents the annexe being used as a separate dwelling or sold separately.

Read the wording carefully before the decision is issued. Conditions that are drafted too tightly can cause problems later, for example if the dependent relative's circumstances change and a carer needs to occupy instead. Where the wording looks unworkable, raise it with the case officer during determination rather than applying to vary it afterwards.

A permitted development point worth knowing. An outbuilding under the householder permitted development rights must be for a purpose incidental to the enjoyment of the dwellinghouse, and accommodation for a relative to live in is generally treated as primary living accommodation rather than incidental. So a garden annexe usually needs planning permission, however it is described on the plans.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it. A Lawful Development Certificate is the only formal way to confirm that works are lawful.

Assembling the pack

Order of work that avoids rework:

1. Check the property for constraints: conservation area, listed building, Article 4 direction, protected trees.
2. Design the annexe as visibly part of the house, with a shared drive and an open garden.
3. Draw the block plan first, because it is the drawing the officer reads first.
4. Write a short statement covering the ancillary relationship and the dependency in general terms.
5. Claim the levy exemption and file the commencement notice before any work starts.

Where the site is more constrained, or where the proposal grows into something closer to a new dwelling, the evidence base widens quickly, much as it does for a demolition and rebuild of a single house. Browse the report types to see what a fuller application involves, and enter your postcode on PlanScope to check which documents your property is likely to need.

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