How Commercial Landlords Can Reduce the Risk of Unauthorised Tenant Alterations

Introduction

Commercial tenants often need to adapt premises to suit their businesses.

An office occupier may wish to install partition walls.

An industrial tenant might require additional electrical equipment.

A warehouse operator may want to construct a mezzanine floor.

These changes can be entirely reasonable and may help a business operate successfully.

However, alterations can also create risks for landlords if they are undertaken without appropriate permission, technical assessment or documentation.

Unauthorised works may affect the building’s structure, fire safety, insurance arrangements or future marketability.

They can also lead to disputes about responsibility for repairs and reinstatement when the tenancy ends.

For commercial landlords across Bury, North Manchester and Greater Manchester, managing tenant alterations is an important part of protecting the property.

The objective is not to prevent reasonable improvements. It is to ensure that proposed works are properly assessed, approved and recorded.

What Are Tenant Alterations?

Tenant alterations are changes made to commercial premises during occupation.

They can range from relatively minor internal modifications to substantial structural works.

Examples include:

• Installing partition walls
• Creating additional offices
• Adding mezzanine floors
• Altering electrical installations
• Installing extraction systems
• Changing loading doors
• Adding external equipment
• Modifying drainage

The legal treatment depends on the lease, the nature of the works and applicable law.

Why Tenants Want to Alter Premises

Businesses rarely remain completely unchanged throughout a commercial tenancy.

A company may expand, introduce new equipment or change its internal processes.

For example, a warehouse operator may require additional office accommodation.

A manufacturer may need upgraded power distribution.

A professional services business may want more meeting rooms.

These alterations can help the tenant remain in the premises.

Alterations Can Benefit Landlords

Where properly designed and documented, certain improvements may increase the building’s usefulness.

They may also support tenant retention.

However, not every alteration adds value.

Highly specialised works can make premises less suitable for future occupiers.

Landlords should therefore consider both the tenant’s immediate requirements and the property’s long-term flexibility.

Start With the Lease

The commercial lease is the starting point when assessing alteration rights.

It may distinguish between different types of works.

For example, a lease might treat internal non-structural alterations differently from structural changes.

Some works may be prohibited.

Others may require prior written consent.

Certain minor alterations may be permitted without consent, subject to conditions.

Avoid Assuming Every Lease Is the Same

Commercial leases vary considerably.

A landlord should not rely on a general assumption that all alterations require consent or that tenants can undertake any non-structural work.

The actual wording must be reviewed.

A commercial property solicitor can advise on the relevant rights and obligations.

Why Unauthorised Alterations Create Problems

Works undertaken without appropriate approval can create several difficulties.

For example:

• Structural components may be affected.
• Fire-safety arrangements may change.
• Building services may be overloaded.
• Insurance conditions may be breached.
• Planning or building-regulations requirements may not have been addressed.

The landlord may also lack information about what has been installed.

This can complicate future maintenance, repairs and property transactions.

Establish a Clear Consent Procedure

Landlords can reduce uncertainty by establishing a consistent process for alteration requests.

Tenants should know who to contact and what information may be required.

A straightforward procedure can help avoid informal approvals or misunderstandings.

Information to Request

Depending on the works, a landlord may ask for:

• Description of the proposed alterations
• Plans or drawings
• Contractor details
• Technical specifications
• Proposed timetable
• Relevant approvals
• Insurance information

The amount of information should be proportionate to the nature of the project.

A minor internal change may not require the same level of investigation as a structural alteration.

Why Written Consent Matters

Informal conversations can create uncertainty.

A tenant may believe permission has been granted.

The landlord may have intended only to discuss the proposal.

Written documentation helps establish what has been agreed.

Where appropriate, a formal licence for alterations may be used.

What Is a Licence for Alterations?

A licence for alterations is a legal document that can record the landlord’s consent to specified works and set out relevant conditions.

It may address:

• Approved drawings
• Workmanship
• Compliance requirements
• Insurance
• Reinstatement
• Professional costs

The precise provisions depend on the transaction.

Landlord Consent Is Not Always Entirely Discretionary

An important legal consideration is that a landlord’s ability to refuse consent may be restricted by the lease and applicable law.

For example, section 19(2) of the Landlord and Tenant Act 1927 can be relevant to certain improvement works.

The legal position is fact-specific.

Landlords should obtain legal advice before refusing an application or imposing conditions.

Respond Professionally

Even where a landlord has legitimate concerns, it is sensible to explain them clearly.

A structured response can help the parties identify whether the proposal can be amended.

Structural Alterations Require Particular Care

Structural works can have long-term implications for a building.

Examples may include:

• Removing walls
• Altering beams
• Creating openings
• Installing heavy mezzanine structures
• Modifying foundations

These works should not proceed without appropriate technical assessment.

Structural Engineer Involvement

A structural engineer may need to assess the proposed design and its effect on the existing building.

The landlord should consider whether calculations, drawings and completion documentation are required.

The objective is to ensure that alterations do not compromise structural safety.

Mezzanine Floors

Mezzanine floors can provide additional usable accommodation within industrial units.

However, they may affect:

• Structural loading
• Fire safety
• Escape routes
• Sprinkler arrangements
• Building regulations

The landlord should establish whether the proposed installation is suitable.

Reinstatement at Lease Expiry

A mezzanine may be valuable to one occupier but inconvenient for another.

The landlord should consider whether it must remain or be removed at the end of the tenancy.

This should be addressed in the relevant documentation.

Electrical Alterations

Industrial and commercial tenants may need to install additional electrical equipment.

Examples include:

• Distribution boards
• Machinery connections
• Specialist lighting
• Additional sockets
• Charging equipment

These works may affect the existing electrical installation.

Appropriate design, installation and certification are important.

Retain Records

Landlords should consider requiring relevant electrical certificates and updated documentation where appropriate.

This can assist with future maintenance and tenant changes.

Fire-Safety Implications

Alterations can affect a building’s fire-safety arrangements.

For example, installing partitions may change escape routes.

A mezzanine could affect evacuation arrangements.

New machinery may introduce additional fire risks.

The relevant responsible persons and competent professionals should assess the implications.

Consider the Whole Building

In multi-let premises, alterations within one unit may affect shared fire-safety arrangements.

The landlord should consider the wider building rather than assessing the proposed works in isolation.

Planning Permission and Building Regulations

Landlord consent does not replace statutory approvals.

A tenant may need planning permission or building-regulations approval for certain works.

The position depends on the proposal.

The Planning Portal provides general information about planning and building regulations in England.

Establish Responsibility

The licence or other agreement should make clear which party is responsible for obtaining necessary approvals.

The landlord should also consider whether copies of relevant documentation must be supplied.

Insurance Implications

Certain alterations may affect building insurance.

For example, changes involving structural works, hot works or specialist equipment may require insurer notification or additional precautions.

Landlords should review relevant policy conditions before works begin.

Contractors’ Insurance

Where appropriate, the landlord may require evidence of suitable contractor insurance.

The level and type of cover should reflect the nature of the works.

Insurance arrangements should be considered with appropriate professional advice.

Protecting Neighbouring Occupiers

In a multi-let commercial building, alterations may affect other tenants.

Potential issues include:

• Noise
• Dust
• Access restrictions
• Temporary utility interruptions
• Shared fire routes

The landlord should consider how works will be managed.

Agree a Works Programme

For substantial projects, it may be appropriate to establish working hours and access arrangements.

This can help reduce unnecessary disruption.

Avoiding Damage to the Building

Alterations can involve drilling, cutting, lifting and other construction activities.

The landlord should consider whether appropriate methods and supervision are required.

For example, installing equipment on a roof may create risks involving waterproofing and structural loading.

Works should be carried out by competent contractors.

Keep Accurate Records

One of the most useful steps a landlord can take is maintaining a clear alteration file.

This may include:

• Tenant request
• Approved drawings
• Licence for alterations
• Contractor details
• Relevant certificates
• Completion records
• Photographs

These records can be valuable during future lettings, sales and maintenance works.

Why Records Matter to Buyers

A prospective purchaser may ask whether alterations were authorised and properly documented.

Incomplete records can create additional due-diligence questions.

Maintaining documentation can therefore support future transactions.

Completion Inspections

For certain works, the landlord may wish to arrange an inspection after completion.

This can help establish whether the works appear to correspond with the approved proposal.

However, a general inspection does not replace professional certification or statutory approvals.

Where appropriate, the landlord should obtain confirmation from relevant technical professionals.

Reinstatement Obligations

One of the most important issues is what happens when the tenant leaves.

Some alterations may need to be removed.

Others may remain.

The lease and any licence for alterations should be reviewed.

Avoid Leaving Reinstatement Until the Last Minute

A landlord who waits until lease expiry to investigate alterations may face uncertainty.

Clear documentation at the approval stage can help reduce later disputes.

Unauthorised Works Discovered During an Inspection

A landlord may discover alterations that were not previously approved.

The appropriate response depends on the circumstances.

A sensible initial approach may involve:

1. Establishing what works were undertaken.
2. Reviewing the lease.
3. Requesting relevant documentation.
4. Considering technical and safety implications.
5. Obtaining legal advice where necessary.

The landlord should avoid assuming that every unauthorised alteration must automatically be removed.

The legal position and appropriate remedy depend on the facts.

Can Unauthorised Works Be Approved Retrospectively?

In some circumstances, parties may agree to document existing alterations retrospectively.

However, this is not always appropriate.

The landlord may need technical evidence, statutory approvals or remedial works before considering consent.

Retrospective documentation does not automatically resolve all compliance issues.

Alterations and Dilapidations

Tenant alterations can become relevant when assessing obligations at lease expiry.

For example, a tenant may be required to remove certain installations and reinstate affected areas.

However, the position depends on the lease, licences and applicable law.

A specialist dilapidations surveyor and solicitor may need to advise.

A Practical Example

Consider a hypothetical tenant occupying a 4,000 sq ft industrial unit.

The tenant installs a substantial internal mezzanine without approaching the landlord.

During a routine inspection, the landlord becomes aware of the works.

The landlord does not have structural calculations, building-control information or documentation concerning fire safety.

This creates uncertainty.

The appropriate next step is to investigate the works, review the lease and obtain relevant professional advice.

The example illustrates why a clear consent process can be valuable.

Creating a Tenant Alterations Policy

Landlords with multiple commercial units may benefit from a consistent alterations policy.

The policy could explain:

• How requests should be submitted
• What information is required
• Who reviews proposals
• When professional advice may be needed
• How approvals are documented
• What completion records are expected

However, the policy must remain consistent with individual lease rights and applicable law.

It cannot simply override existing contractual provisions.

Frequently Asked Questions

Can a commercial tenant alter premises without landlord consent?

That depends on the lease, the type of alteration and applicable law.

What is a licence for alterations?

It is a legal document used to record consent to specified works and relevant conditions.

Can a landlord refuse permission for tenant alterations?

Sometimes, but the ability to refuse or impose conditions depends on the lease and applicable law.

Who pays for tenant alterations?

Usually this is addressed by the lease or agreement between the parties. The allocation of costs should be confirmed.

Can a landlord require alterations to be removed when the tenant leaves?

Potentially, depending on the lease, any licences and the relevant legal position.

Citrus Commercial Circle’s Market Insight

At Citrus Commercial Circle, we believe commercial landlords should approach tenant alterations in a practical and structured way.

Businesses need flexibility to adapt their premises.

However, landlords also need to protect the building, maintain appropriate records and understand long-term liabilities.

A clear approval process can help both parties.

For landlords across Bury and North Manchester, proper documentation can reduce uncertainty and support effective property management.

Final Thoughts

Tenant alterations are a normal part of commercial property occupation.

They can improve business operations and sometimes enhance the building.

However, unauthorised works can create technical, legal and financial risks.

Landlords should understand the lease, establish a clear consent procedure and obtain appropriate professional advice for significant alterations.

Good alteration management is not about preventing change. It is about ensuring that change is properly planned, authorised and documented.

How Citrus Commercial Circle Can Help

Citrus Commercial Circle works with commercial landlords, investors and occupiers across Bury, North Manchester and Greater Manchester.

Our team provides commercial property agency advice, marketing and local market insight to support effective property decisions.

Based in Bury. Active across North Manchester. Always on your side.

Call us today: 0161 383 1806

Email: info@citruscommercialcircle.co.uk

Visit: https://citruscommercialcircle.co.uk

Let’s unlock the full potential together.

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