It is a common assumption but also a misleading one that planning permission for marquees and structures does not apply.

In reality, UK planning rules do not work like that.

Whether a structure is permanent or temporary is only part of the picture. What matters more is how it is used, where it is located, and the impact it has on the surrounding site and environment.

If you are considering installing a temporary structure, understanding where you stand on planning permission early can help you avoid delays, unexpected costs and disruption to your project.

Why “temporary” does not automatically mean exempt

In planning terms, a marquee or temporary building is still considered development if it changes how land is used or has a material impact on its surroundings.

That means:

• A structure that is in place for a short period can still require planning permission
• A demountable or relocatable building is not automatically exempt
• Planning decisions are based on impact, not just permanence

This is where many projects run into difficulty, particularly when timelines are tight and assumptions are made too early. 

The 28-day rule: useful, but often misunderstood

You may have come across the “28-day rule”, which allows land to be used for a temporary purpose for up to 28 days in a calendar year without full planning permission.

This can apply to scenarios such as:

• Outdoor events
• Temporary storage
• Seasonal use

However, there are some important limitations:

• The 28 days are cumulative across the year, not per use
• It applies to the use of land, not just the structure itself
• It does not override other controls such as licensing, highways or environmental restrictions

In practice, many commercial or operational requirements exceed this threshold, meaning planning permission becomes necessary.

When planning permission is likely to be required

While every project is assessed individually, there are some common triggers that mean permission will usually be needed.

These include:

Duration

• The structure will remain in place for more than 28 days

Size and footprint

• The building has a large floor area (often over 100m² as a general guide) 
• It occupies a significant proportion of the site

Position on site

• Located close to site boundaries (for example within around 5 metres) 
• Likely to affect neighbouring properties

Height and visual impact

• Taller than surrounding structures
• Alters the overall appearance of the site

Operational impact

• Affects traffic flow, access routes or parking arrangements 

Individually, these factors may not always trigger a requirement, but taken together, they form the basis of how planning authorities assess a proposal.

When you might not need planning permission

There are situations where planning permission may not be required, often linked to Permitted Development (PD) rights.

These typically apply where a structure:

• Supports an existing use on the site
• Falls within defined size and positioning limits
• Does not significantly alter the external appearance or function of the site

However, PD rights are highly site-specific.

They can vary depending on:

• The type of property (commercial, educational, agricultural, etc.)
• Previous development on the site
• Local planning restrictions

In some cases, PD rights may have been removed entirely.

Because of this, it is always worth verifying your position before proceeding.

Why location changes everything

Planning sensitivity increases significantly depending on where your site is located.

Additional restrictions are common if your project is:

• Within a conservation area
• Close to or affecting a listed building
• Located in the Green Belt
• Impacting land with protected trees or subject to Tree Preservation Orders (TPOs) 

In these environments, even relatively small or short-term structures can require more detailed assessment.

Temporary permission vs permanent development

One advantage of temporary structures is that planning authorities may be more flexible in granting temporary permission than they would be for a permanent building.

This is often the case for:

• Construction and infrastructure projects
• Short-term operational requirements
• Interim solutions during redevelopment

Because the structure can be removed, planners may view it as a lower-risk option making it a practical route to unlocking space where permanent development would not be approved.

What to expect from the planning process

If planning permission is required, the process is relatively straightforward in most cases.

• Typical decision timeframe is around 8 weeks
• Applications are assessed by your Local Planning Authority (LPA)
• Decisions are based on local planning policy and material considerations

It is also worth noting:

• Objections do not automatically prevent approval
• They must be based on valid planning concerns such as noise, traffic or visual impact 

Early engagement and a well-prepared application can significantly improve the likelihood of a smooth outcome.

A note on retrospective planning

In some cases, it is possible to apply for retrospective planning permission after a structure has been installed.

This is typically used in urgent situations, such as emergency response or disaster recovery 

However, it is not without risk:

• Approval is not guaranteed
• You may be required to remove the structure if permission is refused

For that reason, it is generally better to address planning requirements upfront wherever possible.

The most important takeaway: every site is different

While general rules and thresholds are helpful, there is no universal answer to whether planning permission is required.

Each project depends on:

• The structure itself
• How it will be used
• The characteristics of the site
• The policies of the local authority

Taking advice early (before installation) can help avoid delays, protect budgets and ensure your project runs as planned.

Final thought

Temporary structures are often chosen because they offer speed, flexibility and minimal disruption.

But from a planning perspective, they still need to be approached with the same level of care as any other development.

Getting clarity at the outset makes the rest of the project significantly easier.

Please reach out if you’d like to discuss your project in more detail and to find a suitable temporary structure for your needs.