Granny Annexe Scotland: Planning, Costs & Council Tax
Yes, you can put a granny annexe in your garden in Scotland, but it isn't treated like a garden room. Because people will sleep, cook and wash in it, you'll almost always need planning permission and a building warrant from your council. Council tax may also apply.
This guide explains each step in plain English: what counts as an annexe, which permissions you need, what drives the cost, how council tax works in Scotland, and how long the whole project takes. We design, supply and install self-contained garden annexes across Scotland from our base in Perth, so the advice comes from real projects.
Thinking about an annexe for a parent or grown-up child? Call us on 01738 260552 for a free, no-pressure chat about your garden and what's possible.
What is a granny annexe (and how is it different from a garden room)?
A granny annexe is a self-contained building in the garden of your home, with its own kitchen, shower room and sleeping space. It's linked to the main house: it shares the garden, driveway and usually the utilities, and it's lived in by family or someone connected to the household.
A garden room is for daytime use: an office, gym or hobby space. That difference is what changes the rules.
Garden room | Granny annexe | |
Typical use | Office, gym, studio, snug | Living accommodation for a relative |
Kitchen and shower room | No (or a basic WC) | Yes |
Sleeping overnight | No | Yes |
Planning permission in Scotland | Often not needed under permitted development | Usually needed |
Building warrant | Often not needed under 30m² | Needed |
Utilities | Electrics | Electrics, water, drainage, heating |
People build annexes for many reasons. These are the most common:
an elderly parent who wants independence with family close by
a grown-up child saving for a home of their own
a live-in carer
visiting family and guests
downsizing within your own garden and letting family take the main house
If you only need a home office or extra daytime space, a garden room is simpler and cheaper.
Do you need planning permission for a granny annexe in Scotland?
In most cases, yes. Scotland's householder permitted development rules (Class 3A) only cover garden buildings used for purposes "incidental to the enjoyment" of your home, such as a shed, summerhouse or home office. They don't cover a building that is lived in, so an annexe with a bedroom, kitchen and shower room normally needs a planning application to your council.
That's the key difference from a garden room. We explain the garden room rules in our guide to garden room planning permission in Scotland.
What the council will look at
Planning officers usually focus on a few things:
Ancillary use: the annexe should stay linked to the main house, not become a separate home. Councils often add a condition saying it can't be sold or let separately.
Size and position: whether it looks subordinate to the house and leaves enough garden.
Neighbours: overlooking, overshadowing and how close it sits to the boundary.
Access and parking: especially on tighter plots.
Special designations: stricter rules apply in conservation areas and near listed buildings.
How to apply
Check your plot with us or a planning consultant.
Prepare drawings: site plan, floor plan and elevations.
Apply through the Scottish Government's ePlanning portal or directly with your council, such as Perth & Kinross Council.
Wait for a decision. Councils aim to decide householder applications within two months.
The official rules are set out in the Scottish Government's Planning Circular 1/2024 on householder permitted development rights.
You may read about putting an annexe in under caravan rules, which some English suppliers promote. It depends on how the building is constructed and used, and councils don't all treat it the same way, so always get your council's view in writing before relying on it.
Do you need a building warrant for an annexe?
Yes. In Scotland, small garden buildings up to 30m² can be exempt from a building warrant, but the exemption doesn't apply to a building with a sanitary facility (a toilet, shower or basin) or a fixed combustion appliance like a wood burner. An annexe has a shower room, so it needs a building warrant.
This is set out in Schedule 3 of the Building (Scotland) Regulations 2004.
Planning permission and a building warrant are separate. Planning is about whether you can build it there. The building warrant is about whether it's built safely: structure, insulation and energy use, fire safety, drainage, ventilation and accessibility.
The building warrant process works like this:
Submit a building warrant application with technical drawings and specifications through the eBuildingStandards portal.
Your council's building standards team checks the design and approves it.
The annexe is built to the approved plans.
A completion certificate is submitted and accepted before anyone moves in.
Keep the warrant and completion certificate safe. Solicitors will ask for them if you ever sell the house.
As part of our full project management, we offer planning advice and guide you through what your council will need.
Not sure what your garden needs? Book a free site visit and we'll talk you through planning and warrants before you spend anything.
How much does a granny annexe cost in Scotland?
Most fully fitted garden annexes in Scotland cost between £35,000 and £100,000 installed, depending on size and specification. A compact studio usually costs around £35,000–£50,000, while a two-bedroom annexe can pass £80,000. Groundwork, utility connections and permission fees usually come on top.
Annexe type | Typical size | Layout | Typical installed price |
Compact studio | 18–25m² | Open-plan living, kitchenette, shower room | £35,000–£50,000 |
One-bedroom | 30–36m² | Separate bedroom, kitchen/living area, shower room | £50,000–£70,000 |
Large one-bedroom | 40–48m² | Bigger living space, larger bathroom, storage | £60,000–£85,000 |
Two-bedroom | 55–65m² | Two bedrooms, kitchen/living area, bathroom | £75,000–£100,000+ |
These are typical 2026 prices for fully fitted garden annexes in Scotland, including VAT, kitchen, shower room and installation. Our annexe range is priced competitively within these ranges, and every quote is itemised so you can see exactly what's included.
What affects the price
Size and layout: each extra room adds walls, glazing and fit-out.
Groundwork: base, levelling and access for machinery.
Utilities: the distance from the house to connect water, drainage and electricity is often the biggest variable.
Kitchen and shower room spec: fittings range widely.
Heating: electric panels, an air source heat pump or underfloor heating.
Accessibility: level thresholds, wider doors and grab rails if the annexe is for an older relative.
Fees: planning and building warrant fees, plus drawings.
Extras: decking, paths and landscaping.
For a wider look at what drives garden building prices, see how much a garden room costs.
Do you pay council tax on a granny annexe in Scotland?
Often, yes. If your annexe is self-contained, with its own kitchen, bathroom and living space, the local Assessor may treat it as a separate dwelling and give it its own council tax band. In Scotland, bands are set by the Scottish Assessors, not by the council.
Scotland's rules are different from England's, and this is where many online guides get it wrong:
No dependent relative exemption. England has a "Class W" exemption for an annexe lived in by an elderly or disabled relative. Scotland's list of exempt dwellings has no equivalent.
Empty annexes can be exempt. An unoccupied annexe in the grounds of your home that is difficult to let separately can be exempt while you live in the main house.
Discounts may still apply. If one adult lives in the annexe, the 25% single person discount may apply to its bill. Other discounts depend on who lives there.
Council tax depends on your situation, so check with your council's council tax team before you build.
If you're weighing up the extra cost, it's also worth reading whether a garden building adds value to your home.
How to choose the right annexe layout
Start with who will live there and how that might change over the next 10–15 years. An annexe for a fit 70-year-old should still work if they later need a walking frame or a carer.
Ask yourself these questions:
One person or two? A studio layout suits one person. A separate bedroom gives a couple or a carer more privacy.
Will mobility change? Plan level access, a walk-in shower, wider doorways and space to turn a wheelchair from the start.
How close to the house? Near enough to pop over, far enough for privacy, and with a lit, level path between them.
Outdoor space? A covered porch or small deck makes a big difference to daily life.
Future use? Could it become guest space or a home office later?
Our annexe and lodge range includes studio, two-room and open-plan designs. We can adapt any of them to suit your garden and the person living there.
Utilities, groundwork and access: what's involved
An annexe needs proper services, and this is where projects most often run over budget if they're not planned early.
Electricity: a dedicated supply from your consumer unit, sized for cooking, hot water and heating.
Water: a new supply pipe from the house, insulated against frost.
Drainage: foul water usually connects to your existing drains. If your home is on a septic tank, its capacity needs checking.
Base: a level, durable base designed for your ground conditions.
Access: how materials and machinery reach the back garden.
Scottish winters add another reason to get the spec right. Our guide to garden rooms in a Scottish winter covers insulation, heating and condensation, and the same principles apply to an annexe that's lived in all year.
How long does it take to build a granny annexe?
Once permissions are in place, the build itself usually takes 6–8 weeks, depending on the design and site. Allow extra time before that for planning and building warrant approval.
Stage | Typical time |
Site visit, design and quote | A few weeks |
Planning permission | Around 2 months |
Building warrant | Varies by council, and can run alongside planning |
Build and fit-out, including groundwork and services | 6–8 weeks |
Completion certificate | After the build, before anyone moves in |
If you'd like someone to move in by a particular date, start the conversation around six months ahead.
Common mistakes to avoid
Assuming garden room rules apply. Sleeping accommodation changes everything.
Building before permissions are granted. Retrospective applications are stressful and can be refused.
Forgetting drainage and water costs. Get the services priced at quote stage, not after.
Designing for today only. Level access is far cheaper to build in than to add later.
Ignoring council tax. Factor it into the running costs.
Skimping on insulation. A building lived in all year needs a proper spec for Scottish weather.
Ready to talk it through? Call us on 01738 260552 or send us your enquiry and we'll arrange a free site visit.
Granny annexe FAQs
Can I rent out my granny annexe as a holiday let?
Not without the right permissions. A planning condition often ties an annexe to the main house. Short-term lets in Scotland also need a short-term let licence from the council. If a holiday let is your main aim, apply for that use from the start.
Can I live in the annexe and let my family have the main house?
Yes, this is a popular way to downsize without moving away. The annexe still needs to stay linked to the main house in planning terms, so make sure your application describes how it will be used.
Can a granny annexe be sold separately from the house?
Usually not. Councils commonly add a condition stopping an annexe being sold or let as a separate home. Turning it into an independent house would need a new planning application.
How big can a granny annexe be in Scotland?
There's no fixed maximum, because annexes go through a full planning application. Councils judge each one on its size compared with the house and garden, its impact on neighbours and its design. Our annexe designs are sized to work well in typical Scottish gardens.
Can I build an annexe in a conservation area?
Yes, but the design will get closer scrutiny. Materials, height and position matter more, and a listed building may also need listed building consent. Speak to us early so the design fits the setting.
Is a granny annexe right for your family?
A granny annexe lets a relative live independently while staying close to the people they love. In Scotland, plan for planning permission, a building warrant and council tax from day one, and budget for services as well as the building.
Get those right and you'll have a comfortable, warm home in your garden that works for years.
Speak to Glenview Retreats. Call 01738 260552 or request a free site visit. We'll look at your garden, talk through planning and warrants, and give you a clear quote for the right annexe. You can also browse our annexe range first.
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