A garden room can be a practical way to create additional space without extending the main house. Depending on its design and intended use, a garden room could provide a home office, studio, gym, hobby room, playroom or another useful space.
However, before buying a garden room or starting construction, it is important to establish whether garden room planning permission is required.
Some garden rooms can benefit from permitted development rights, but these rights are subject to specific limitations and conditions. The position can depend on the building’s height, location, size, use and the planning circumstances of the property.
The term “garden room” also covers many different types of building. A simple home office is not necessarily treated in the same way as a self-contained building designed for permanent accommodation.
Do You Need Planning Permission for a Garden Room?
Not necessarily.
A garden room may be capable of being built under permitted development rights where it is an outbuilding within the curtilage of a dwellinghouse and all relevant requirements are satisfied.
The permitted development framework allows certain buildings and structures within the curtilage of a dwellinghouse where they are required for a purpose incidental to the enjoyment of the house.
However, the fact that a building is marketed as a “garden room” does not automatically mean planning permission is unnecessary.
The following factors should be considered:
All relevant requirements need to be considered together.
What Can You Use a Garden Room For?
The intended use is one of the most important aspects of the planning assessment.
A garden room might be used as:
Where the building remains ancillary to the main house, it may potentially fall within permitted development rights.
However, a building intended to operate as independent residential accommodation is different.
The use should therefore be decided before the design is finalised.
Garden Room Height Restrictions
Height is one of the most important planning considerations.
For outbuildings relying on permitted development rights, the eaves height is generally limited to 2.5 metres. The maximum overall height depends on the roof design, and additional restrictions apply where the building is within two metres of the boundary.
This can have a major effect on the design.
For example, you may want a garden room with:
If the building is close to the boundary, the applicable height restriction can limit the available design.
Height should therefore be checked before purchasing a garden room based solely on a manufacturer’s standard dimensions.
How Close Can a Garden Room Be to a Boundary?
A garden room can potentially be positioned close to a boundary, but its height can be affected.
Where any part of an outbuilding is within two metres of the boundary, the maximum overall height is generally restricted to 2.5 metres.
This means that moving a building closer to the boundary can have consequences for the roof design.
Measurements should be taken carefully.
Consider:
A small measurement difference can affect whether the proposed design fits within the relevant requirements.
How Much of the Garden Can a Garden Room Cover?
The garden room should not be assessed in isolation.
Permitted development rules can restrict the total area of the curtilage that can be covered by additions and other buildings.
Existing development may therefore need to be considered.
This can include:
A property that has already been substantially extended may have less available permitted development capacity than a property that has not been altered.
The garden room should therefore be assessed alongside the existing development.
Where Can a Garden Room Be Built?
The location of the garden room is important.
Permitted development rules can restrict buildings positioned forward of a wall forming the principal elevation of the original dwellinghouse.
For a conventional house, this generally means that a garden room positioned behind the main front elevation is more likely to be within the relevant permitted development provisions.
However, individual properties can have unusual layouts.
Corner houses, properties with unusual orientations and homes with multiple prominent elevations may need more careful assessment.
The site plan should therefore be considered before deciding where the garden room will go.
Does a Garden Room Have to Be Single Storey?
A garden room relying on the relevant permitted development rights should be single storey.
This means that a two-storey garden building is a different proposition.
Similarly, proposals involving substantial raised platforms or more complex structures need to be assessed carefully against the applicable requirements.
If additional space is required, the design should be considered carefully within the available planning limits.
Trying to maximise the size of the garden room without considering planning restrictions can lead to an unsuitable design.
Can You Use a Garden Room as a Home Office?
A garden room used as a home office can often be compatible with the use of the property as a dwelling.
For example, someone working remotely from a desk in a garden room may still be using the building for a purpose associated with the enjoyment of the home.
However, more intensive business activity can create different planning considerations.
This can include:
The actual nature and intensity of the business should therefore be considered.
A quiet home office is not necessarily comparable to a commercial premises operating from the garden.
Can a Garden Room Have a Toilet?
A garden room can potentially contain facilities such as a toilet, but this should not be considered in isolation.
The question is what the building will actually be used for.
A toilet in a home office does not automatically mean that the building becomes a separate dwelling.
However, if the garden room contains:
the planning position may be different because the building could be capable of functioning as independent accommodation.
The overall proposal should therefore be assessed rather than focusing on one individual feature.
Can You Put a Kitchen in a Garden Room?
A kitchen can raise additional planning questions because it can contribute to the building functioning independently from the main house.
This does not mean that every garden room containing kitchen facilities automatically requires planning permission.
The intended use and overall arrangement are important.
A garden building designed as a self-contained home is materially different from a hobby room with a small kitchenette used by the household.
If the building is intended to provide independent accommodation, the planning position should be established before construction.
Can You Use a Garden Room as a Bedroom?
You should not assume that a garden room can automatically be used as independent sleeping accommodation.
A building designed as an ancillary room is different from a building intended to function as a separate residential unit.
If the proposed use is effectively:
planning permission may be required.
The physical design and intended use should therefore be considered together.
Garden Room for Guests or Family Members
Homeowners sometimes want to use a garden room to provide accommodation for guests or family members.
The planning implications depend on the nature of the accommodation.
Occasional use connected with the main dwelling may have a different planning position from permanent independent occupation.
If the garden room is designed to operate as a self-contained annexe, the proposal should be assessed before construction.
It is not enough to rely on the fact that the building is technically located within the garden.
What About a Garden Room in a Listed Property?
Listed buildings require additional care.
Planning controls affecting listed buildings can restrict permitted development rights, and works may also require listed building consent depending on their nature.
A garden room within the curtilage of a listed building can therefore have a different planning position from a similar building at an ordinary house.
Before purchasing or constructing a garden room, establish whether the property has any heritage or planning designation.
Can a Garden Room Be Built in a Conservation Area?
Additional planning restrictions can apply in designated areas.
The permitted development rules contain specific restrictions relating to certain designated land. The position should therefore be checked before assuming that the standard rules for an ordinary house apply.
This is particularly important where the garden room is proposed close to a side boundary or where the property has other planning restrictions.
Garden Room Planning Permission and Building Regulations
Planning permission and Building Regulations are separate.
A garden room may not require a planning application but can still need to comply with Building Regulations depending on its size, construction and intended use.
Building Regulations can relate to matters such as:
The intended use can also affect the technical requirements.
For example, a building designed as permanent accommodation can have different technical considerations from a simple detached garden structure.
Should You Get a Lawful Development Certificate?
If a garden room is believed to qualify as permitted development, a Lawful Development Certificate can provide formal confirmation of the planning position.
This is not the same as planning permission.
The certificate provides evidence that the proposed or existing development is lawful from a planning perspective where the relevant requirements are satisfied.
It can be particularly useful when selling the property.
A purchaser or solicitor may want evidence that the garden room was lawfully constructed.
For a proposed garden room, obtaining confirmation before construction can provide greater certainty.
What If You Already Built the Garden Room?
If a garden room has already been constructed, establish the planning position before assuming that retrospective planning permission is required.
The building may already be lawful under permitted development rights.
Alternatively, it may require a Lawful Development Certificate or retrospective planning application.
The exact dimensions, location, use and planning history should be reviewed.
If the building does not comply with the relevant planning requirements, enforcement issues can arise.
Garden Room Planning Checklist
Before purchasing or building a garden room, check:
1. The proposed location
Make sure its position within the garden has been assessed.
2. The height
Measure the eaves and overall height.
3. Boundary distance
Check whether the building is within two metres of the boundary.
4. Existing development
Consider extensions, garages and other structures already covering the garden.
5. Intended use
Decide whether the building is an office, studio, gym, accommodation or another use.
6. Property restrictions
Check whether permitted development rights have been restricted.
7. Listed or designated status
Establish whether additional planning controls apply.
8. Building Regulations
Consider the technical requirements separately from planning.
For further guidance on planning permission generally, see our article on Planning Advice for Planning Permission.
How Can Expert Planning Consultants Help?
Garden rooms can appear simple, but relatively small differences in height, location, size and use can change the planning position.
At Expert Planning Consultants, we can assess your proposed garden room against the relevant planning considerations.
This can help establish whether permitted development rights may apply, whether restrictions affect the property and whether a planning application or Lawful Development Certificate may be appropriate.
Professional advice can be particularly useful where you want a larger garden room, are building close to a boundary, intend to work from the building or are considering bathroom or kitchen facilities.
Obtaining advice before ordering the building can also help prevent costly design changes later.
Frequently Asked Questions
Do all garden rooms need planning permission?
No. Some garden rooms can benefit from permitted development rights if the relevant requirements are satisfied.
How tall can a garden room be without planning permission?
The permitted height depends on the design and position of the building. Eaves and overall height restrictions apply, with additional restrictions where the building is within two metres of a boundary.
Can I build a garden room on the boundary?
A garden room can potentially be positioned close to a boundary, but the applicable height restriction must be considered.
Can I use a garden room as an office?
Yes, ordinary home working can potentially be compatible with permitted development where the use remains incidental to the dwelling.
Can I put a toilet in my garden room?
A toilet does not automatically mean planning permission is required. The overall design and intended use should be considered.
Can I put a kitchen in a garden room?
A kitchen can contribute to the building functioning as independent accommodation, so the complete proposal should be assessed.
Can I sleep in a garden room?
You should not automatically assume that a garden room can lawfully be used as independent sleeping accommodation. The intended use needs to be considered.
Do garden rooms need Building Regulations?
Building Regulations are separate from planning permission. Whether approval is required depends on factors including the building’s size, construction and intended use.
Should I get a Lawful Development Certificate?
If you believe the garden room qualifies as permitted development, a Lawful Development Certificate can provide formal evidence of its planning status.
Planning Your Garden Room With Confidence
Garden room planning permission depends on more than the size of the building.
The position, height, boundary distance, amount of existing development, intended use and planning circumstances of the property all need to be considered.
A garden room used as a home office or hobby space may potentially benefit from permitted development rights, while a larger building or one intended to provide independent accommodation may require a different planning approach.
Planning permission should also be considered separately from Building Regulations.
Contact us today to discuss your garden room proposal and find out what planning considerations may apply. We can assess your proposed garden room and help identify the appropriate planning route before you commit to construction.