Temporary structures can provide valuable additional space for businesses, schools, construction projects, events and community activities. They can include modular buildings, marquees, temporary offices, site cabins, storage structures, exhibition spaces and other buildings or installations designed to remain in place for a limited period.
However, describing a building as “temporary” does not automatically mean that planning permission is unnecessary.
In planning terms, the status of a temporary structure depends on the circumstances of the development, including its purpose, duration, location, physical characteristics and relationship with the land on which it is placed. Certain permitted development rights specifically provide for temporary buildings, structures or uses, while a local planning authority can also grant planning permission for a specified temporary period.
Planning Build provides professional support with planning advice, feasibility assessments, planning applications, architectural design and building regulations. Our team can help assess your proposed temporary structure and determine an appropriate planning strategy.
What Is a Temporary Structure in Planning Terms?
In planning terms, a temporary structure is generally a building, installation or other physical development that is intended to remain in place for a limited period rather than forming part of a permanent development.
However, there is no single definition that means every structure described as “temporary” is automatically treated in the same way.
Planning legislation contains specific permitted development rights for certain temporary buildings, structures and uses.
For example, Class A of Part 4 of Schedule 2 to the relevant permitted development regime allows certain buildings, moveable structures, works, plant or machinery to be provided temporarily in connection with operations being carried out on land, for the duration of those operations.
There are also permitted development rights covering certain temporary uses of land. Class B of Part 4 allows specified temporary uses of land for no more than 28 days in total in any calendar year, subject to the conditions and limitations of the relevant right.
This is important because “temporary structure” is not, by itself, a blanket planning exemption.
The planning position needs to be established based on the specific proposal.
What Makes a Structure Temporary?
Several factors may help determine whether a structure or use should be considered temporary in planning terms.
Intended Duration
The intended period for which the structure will remain in place is an important consideration.
A marquee installed for a weekend event is clearly different from a modular office intended to remain on a site for five years.
However, there is no universal rule stating that every structure becomes permanent after a particular number of days.
Some specific permitted development rights have defined time limits, while temporary planning permission can authorise development for a period specified by the local planning authority.
Purpose of the Structure
The reason for installing the structure can also affect its planning position.
A structure may be required temporarily:
- During construction
- During refurbishment
- While a permanent building is being developed
- For an event
- For seasonal activities
- To provide temporary school accommodation
- For a trial commercial use
- As a short-term community facility
- To provide temporary storage or workspace
The purpose should be clearly identified when assessing whether a particular planning right or permission applies.
Physical Characteristics
A structure does not necessarily have to be permanently fixed to the ground to have planning implications.
Modular buildings, portable offices and demountable structures can still constitute development depending on the circumstances.
Relevant physical characteristics may include:
- Size
- Height
- Floor area
- Construction
- Foundations
- Connections to services
- Permanence of installation
- Relationship with existing buildings
A structure that can technically be dismantled may still have a substantial planning impact if it occupies a site for a significant period.
Use of the Land
Planning is concerned with both physical development and the use of land.
This means that a temporary structure may be associated with a change or intensification of land use that itself requires planning consideration.
For example, placing a temporary building on land to operate as a restaurant, office, workshop or retail unit may involve planning issues relating to the use of the land, not simply the structure.
Government guidance notes that temporary uses can help make effective use of vacant or under-utilised land, but planning permission will usually be required for material changes of use or temporary uses incorporated into longer-term development, depending on the circumstances.
Temporary Structures and the 28-Day Rule
The 28-day rule is one of the most commonly misunderstood aspects of temporary structures.
Certain permitted development rights allow specific temporary uses of land for no more than 28 days in total in any calendar year.
For example, Class B of Part 4 provides for the temporary use of land for up to 28 days in a calendar year, with specific limitations on certain uses. It also allows moveable structures to be provided for the permitted use.
However, this does not mean:
- Every temporary structure can remain for 28 days without permission
- Every type of temporary land use qualifies
- A structure can automatically be installed for 28 days anywhere
- Planning permission is unnecessary simply because a structure is removable
The specific permitted development right must apply to the proposal, and its conditions and limitations must be satisfied.
There are also other permitted development rights dealing with temporary structures in particular circumstances.
For example, temporary buildings and structures may be permitted where they are required in connection with operations taking place on land, and they may remain for the duration of those operations.
This demonstrates why the phrase “28-day rule” should not be used as a universal answer to questions about temporary structures.
Temporary Planning Permission
A temporary structure can also be authorised through a specific planning permission.
Under Section 72 of the Town and Country Planning Act 1990, a local planning authority may grant planning permission for a specified temporary period.
This can be appropriate in circumstances where there is a genuine planning reason for limiting the development to a temporary period.
Government guidance gives examples including:
- Trial runs to assess the effects of a development
- Situations where planning circumstances are expected to change
- Temporary use of vacant land
- Temporary use of buildings before longer-term proposals are implemented
- Certain temporary school facilities
A temporary planning permission can therefore allow a structure or use to remain for significantly longer than the periods associated with certain permitted development rights.
The permission should be checked carefully to establish the exact period authorised and any conditions attached to it.
There is also no automatic assumption that a temporary planning permission will subsequently become permanent. Government guidance specifically states that there is no presumption that temporary permission will later be granted permanently.
Temporary Structures During Construction
Construction projects are one of the clearest examples of structures that may be temporary in planning terms.
A development site may require:
- Site offices
- Welfare facilities
- Storage buildings
- Security cabins
- Temporary workshops
- Site accommodation
- Plant and machinery
The permitted development framework contains a specific right for temporary buildings, structures, works, plant or machinery required in connection with operations being carried out on land for the duration of those operations.
This means that a temporary site office connected directly to an authorised construction project may have a different planning position from an independent office installed on a separate site.
The purpose and connection to the underlying operation are therefore important.
Once the main construction works have finished, the continued presence or use of the temporary structure may need to be reassessed.
Temporary Structures for Events
Events frequently involve temporary structures such as:
- Marquees
- Stages
- Temporary seating
- Exhibition structures
- Hospitality areas
- Temporary bars
- Market stalls
- Covered areas
Certain temporary uses of land can benefit from permitted development rights, subject to specific limitations.
For example, the relevant Class B right allows certain temporary uses for up to 28 days in a calendar year.
However, event organisers should not assume that every element of an event automatically falls within this provision.
The proposal may involve separate considerations relating to:
- Land use
- Traffic
- Parking
- Noise
- Access
- Public safety
- Structures
- Environmental impact
- Neighbouring properties
The scale and nature of the event can therefore affect the planning position.
Semi-Permanent Structures and Planning
Some structures are described as “semi-permanent” because they are designed to remain in place for an extended period but can eventually be dismantled or relocated.
Examples include:
- Modular classrooms
- Temporary offices
- Storage buildings
- Modular commercial units
- Industrial structures
- Temporary healthcare buildings
Being demountable does not automatically make these structures temporary in planning terms.
A modular building that remains on a site for several years and operates as a permanent workplace may require planning permission even though the building could technically be dismantled.
The planning authority is likely to consider the actual circumstances of the proposal rather than simply the manufacturer’s description of the building.
Planning Permission and Temporary Structures
Whether planning permission is required depends on the specific development.
A temporary structure may require planning permission where:
- No relevant permitted development right applies
- The proposal exceeds the limitations of a permitted development right
- The use of the land represents a material change of use
- The structure is intended to remain for a period not covered by an applicable right
- The site is subject to restrictions affecting permitted development
- The proposal forms part of a wider development requiring permission
The location of the site can also be important.
Planning considerations may be particularly sensitive where a temporary structure is proposed within or near:
- Green Belt land
- Conservation areas
- Listed buildings
- Heritage assets
- Protected landscapes
- Residential areas
- Environmentally sensitive locations
A temporary structure can still have a visual, environmental or operational impact.
Temporary Structures and Building Regulations
Planning permission and Building Regulations are separate matters.
Planning permission considers whether a development is acceptable in its location and in relation to relevant planning policies.
Building Regulations focus on technical standards relating to the construction and safety of buildings.
Depending on the structure, Building Regulations may address:
- Structural stability
- Fire safety
- Ventilation
- Accessibility
- Drainage
- Energy efficiency
- Sanitation
Some temporary buildings may be exempt from certain building regulations requirements depending on the circumstances and intended duration.
However, this should not be confused with planning permission.
A structure could be exempt from building regulations but still require planning permission.
Equally, planning permission does not automatically mean that the structure complies with building regulations.
Both systems should be considered separately.
What Happens If a Temporary Structure Stays Longer Than Intended?
If a temporary structure remains beyond the period authorised by a permitted development right or planning permission, its continued use may become unauthorised.
This can create planning enforcement risks.
Depending on the circumstances, the local planning authority may investigate and potentially require the structure or use to cease.
If you know that the structure will be needed for longer than originally anticipated, it is better to review the planning position before the authorised period expires.
A further planning application may be appropriate depending on the circumstances.
However, a temporary permission is not automatically renewed. Government guidance notes that a second temporary permission will rarely be justified unless there is a clear reason based on changing circumstances.
How to Assess a Temporary Structure Before Installation
Before installing a temporary structure, consider:
1. What Will It Be Used For?
Clearly define the proposed use.
An event structure, classroom, office and storage building can raise very different planning considerations.
2. How Long Will It Remain?
Establish the actual intended duration rather than simply describing the structure as temporary.
3. Does a Permitted Development Right Apply?
Check whether a specific permitted development right covers the proposed structure or use and whether all conditions and limitations can be met.
4. Does the Use of the Land Change?
Consider whether the structure will introduce a new use or materially alter the existing use of the site.
5. Are There Site Constraints?
Check for relevant planning constraints and designations that could affect the proposal.
6. Are Other Approvals Required?
Planning permission may not be the only consideration. Building Regulations, highways, environmental, licensing or other requirements may apply depending on the project.
How Planning Build Can Help
Understanding what a temporary structure means in planning terms can be difficult because the answer depends on the specific planning right, site, use and circumstances.
Planning Build can help you assess your proposal before installation and identify the appropriate route.
Our services include:
- Planning permission advice
- Planning application support
- Feasibility advice and planning strategy
- Architectural design
- Building Regulation compliance
- Planning appeal support
Early planning advice can help identify potential restrictions, establish whether permission may be required and reduce the risk of investing in a structure before its planning position is understood.
Frequently Asked Questions
What is a temporary structure in planning terms?
A temporary structure is generally a building, installation or other physical development intended to remain in place for a limited period. However, planning law does not treat every structure described as temporary in the same way. The applicable planning rights and circumstances need to be assessed individually.
Does a temporary structure always need planning permission?
No. Certain permitted development rights cover specific temporary structures and uses. However, those rights have conditions and limitations, so a temporary structure is not automatically exempt from planning permission.
Is the 28-day rule the definition of a temporary structure?
No. The 28-day period applies to specific permitted development rights covering certain temporary uses of land. It is not a universal definition of what constitutes a temporary structure in planning terms.
Can a temporary structure stay for several years?
Potentially. A local planning authority can grant permission for a specified temporary period where there is a planning justification for doing so.
Are modular buildings temporary structures?
They can be, but being modular or relocatable does not automatically determine their planning status. The intended duration, use, location and circumstances of the development must be considered.
Do temporary structures need Building Regulations approval?
Some may be exempt from particular Building Regulations requirements, while others may require approval. Building Regulations are separate from planning permission and should be assessed independently.
Get Planning Advice for Your Temporary Structure
Understanding what a temporary structure is in planning terms requires more than looking at whether a building can be dismantled or how long it is expected to remain.
The planning position can depend on the structure’s purpose, intended duration, use of the land, location and whether a specific permitted development right or temporary planning permission applies.
If you are considering a temporary office, modular building, classroom, event structure, storage facility or another temporary development, Planning Build can help you assess the proposal and determine the appropriate planning approach.
Explore Planning Build’s services or contact our team to discuss your project.
