It often surprises homeowners to hear that in some cases, building work or changes to a property can become lawful after enough time has passed. You might imagine that the local authority has unlimited power to enforce against unauthorised work, no matter how long ago it was carried out. In reality, planning law in the UK sets time limits on how long councils can act.
This is where the ten year rule comes in. It is often mentioned in property forums, solicitor letters and conversations with neighbours, but it is one of the most misunderstood areas of property law. The confusion comes from mixing up planning permission and building regulations. While they work alongside each other, they serve very different purposes.
So, what exactly is the ten year rule? How does it connect to new planning laws and the building regulations? And most importantly - does it apply to you?
The ten year rule is a concept in UK planning law. It provides that if a building or piece of land has been used for a certain purpose for at least ten years, without planning permission and without enforcement action, that use may become lawful.
For example, imagine a commercial building that has been used as housing for more than ten years. Even if planning permission for change of use was never granted, the local authority may no longer be able to enforce against it. The owner can apply for a certificate of lawfulness under the ten year rule, which confirms that the use is now legally accepted.
Here is the crucial point: the building regulations ten year rule is not the same as the planning one. In fact, there is no true ten year rule in building regulations. While planning enforcement can run out, building regulation enforcement periods work differently.
A certificate of lawfulness does not confirm that a project meets building regulations. It simply prevents the council from taking action against the unauthorised use.
The ten year planning rule is about land use. Common examples include:
A house converted into flats without planning permission
A shop used as a home for a decade or more
Property change of use such as agricultural land used for storage or commercial purposes
The test is continuity. The unauthorised use must have gone on for ten years without a break. If the use paused, or if the council can show it stopped at any point, the ten-year clock resets.
Alongside the ten year rule are other limits that can cause confusion. The four and ten year rule covers operational development such as building a dwelling, but planning law changes in 2023 reduced the scope of the four year rule. The seven year rule sometimes applies in cases of deliberate concealment. The twelve year rule is linked to land ownership disputes.
It is also worth noting that planning permission itself is normally valid for three years from the date of approval. That is very different from the ten year enforcement rule.
Another way of dealing with unauthorised work is through retrospective planning permission. This allows you to apply for consent after the work has already been carried out. The council will review the application in the same way as if it had been submitted beforehand.
If approved, the development is regularised. If refused, you may face enforcement action.
In practice, after ten years of continuous use you may not need to apply at all, since enforcement is out of time. But proof is crucial. You may still need to make a planning application for change of use if the circumstances do not meet the criteria for the ten year rule.
Again, this relates only to planning. Even if the ten year rule protects you from planning enforcement periods, you may still face retrospective building regulations issues.
A major misconception is that the ten year rule exists for building regulations. In reality, there is no automatic immunity from breaches of building regulations.
Building regulations cover areas like:
Fire safety
Structure and stability
Insulation
Drainage and ventilation
Electrical safety
The building regulations enforcement period is usually within twelve months, but councils can act much later if there is a safety concern. Unlike planning permission, building regulations do not expire. They remain relevant as long as the building stands.
Some projects are exempt from building regulations, such as certain small outbuildings, but most habitable spaces need sign-off.
Bodies like LABC building control or independent building control inspectors are responsible for approvals. Without their certificate, buyers and mortgage lenders can be reluctant.
Loft conversions are one of the most common areas of confusion. A homeowner might install a loft space conversion in a small terraced house, or even a loft conversion on a bungalow, but not apply for planning and building regulation approvals.
Later down the line when trying to sell the property, problems arise. Solicitors ask for paperwork to show statutory approvals and without them the sale slows down or falls apart.
Consider an extension over ten years old. Some owners assume this means they are safe. While planning enforcement may no longer apply, a breach of building regulations time limit remains relevant.
If you think the ten year planning rule applies, apply for a certificate of lawfulness. You’ll need evidence such as dated photographs, utility bills, rental agreements and sworn statements.
For retrospective building regulations issues, you may need regularisation. That means drawings, inspections and sometimes changes. Having clear building regulation drawings ready is essential.
Professional help can explain whether the ten year rule applies or whether you need a retrospective planning application or even indemnity insurance.
The ten year rule in planning law is a useful protection, but it only applies to planning. There is no equivalent building regulations ten year rule.
Understanding the difference between planning and building control is crucial. Planning law changes in 2023 have already altered how enforcement works and further reforms may come.
If you are unsure, seek professional building regulation advice. Knowing the difference between permissive development, planning permissions and enforcement periods will save stress later.
Do not wait until you try to sell or remortgage. By acting early, you protect your property, your finances and your peace of mind.
At Marraum, we specialise in guiding clients through the complexity of planning law and building regulations. Whether it is retrospective planning permission, building regulation drawings, or navigating changes to building regulations in 2023, we can help.
Get in touch with us today to discuss your project and move forward with confidence.