EPC for Maisonettes in London: What Owners and Landlords Should Know

Maisonettes are a common type of property across London, particularly in converted Victorian houses, purpose-built residential buildings and properties arranged over two floors. However, when selling or renting a maisonette, owners may have questions about Energy Performance Certificates (EPCs), especially when the property shares walls, roofs, entrances or heating systems with other homes.

An EPC for a maisonette in London provides information about the property’s energy efficiency and includes recommendations for potential improvements. The assessment depends on the individual dwelling, its construction, insulation, heating arrangements and other relevant features.

Understanding these factors can help homeowners, landlords and property investors prepare for an assessment and organise the correct documents before marketing a property.

Does a Maisonette Need an EPC in London?

In most cases, a self-contained maisonette requires an EPC when it is sold or rented out, unless an applicable exemption applies.

The precise requirements depend on the property, how it is used and the circumstances of the transaction. A maisonette does not automatically become exempt because it forms part of a larger building.

Before arranging an assessment, check whether a valid certificate already exists. You can use the official GOV.UK Find an Energy Certificate service to search for an existing EPC.

You can also read the government’s Energy Performance Certificate guidance for selling and letting homes for further information about certificate requirements and validity.

An EPC is generally valid for ten years unless a newer certificate replaces it. Therefore, you may not need a new assessment simply because ownership changes or a property is offered to a new tenant.

What Is a Maisonette, and Why Does Its Layout Matter?

A maisonette is generally a self-contained dwelling that occupies more than one level or has a layout that distinguishes it from a conventional single-level flat. The exact arrangement varies between buildings.

For example, a London maisonette might occupy the ground and first floors of a converted house. Another might sit above a shop or form part of a purpose-built residential development.

These differences matter because the property’s construction and relationship with the surrounding building can affect its energy performance.

An assessment may need to establish relevant details such as:

• Whether the property is on one level or several.

• Which walls adjoin other dwellings.

• Whether the roof or floor is exposed to outside conditions or an unheated space.

• The type of windows and external doors.

• The heating and hot water arrangements.

• The insulation and construction of relevant building elements.

If your property forms part of a newly constructed development, our guide to EPC for new-build homes in London explains what owners should know about certificates, construction specifications and energy-related documentation.

For maisonettes created from older buildings, it is particularly important to establish which parts of the original structure belong to the dwelling being assessed.

How Does a Maisonette’s Construction Affect Its EPC Rating?

A maisonette’s energy rating is not determined simply by the number of floors or the age of the building. Instead, the assessment considers the property’s relevant energy-performance characteristics using the applicable methodology.

1. Walls and Insulation

Some maisonettes have external walls exposed to outdoor temperatures, while others share walls with neighbouring dwellings.

The construction type, insulation and amount of exposed wall area can affect how heat moves through the property.

Older London buildings may have solid masonry walls, while newer developments may use different construction systems. Insulation may also have been added during renovation.

If you have carried out insulation work, keep the available installation records and technical specifications.

Our guide to EPC assessment evidence for London property owners explains why documents can be helpful when some building features are concealed.

2. Roofs and Floors

A maisonette on the top floor may have different heat-loss characteristics from one located between two heated dwellings.

Similarly, a ground-floor maisonette above an unheated space may have different characteristics from a property with another heated dwelling directly beneath it.

The assessor needs to establish the relevant construction and adjoining spaces rather than assume every maisonette has the same thermal performance.

If you are planning insulation improvements, consider the building’s construction and seek appropriate professional advice before carrying out major work.

3. Windows and External Doors

Windows and external doors can influence heat loss and the property’s overall energy performance.

The relevant details may include the type of glazing, frames and other features recorded during the assessment.

If you have recently replaced windows or doors, retain any available invoices and product specifications.

However, new windows do not guarantee a particular EPC rating. Their contribution depends on the property’s other characteristics and the assessment methodology.

4. Heating and Hot Water

Maisonettes can have individual boilers, electric heating, heat pumps or systems that serve multiple dwellings.

The type of heating system, its controls and the hot water arrangements can all be relevant to the assessment.

If your property uses underfloor heating, read our guide to underfloor heating and EPC ratings in London to understand why the installed system and the rest of the property need to be considered together.

Where a maisonette uses a heat pump, our article on EPC for heat pumps in London provides additional information about heating technology and property energy performance.

What If the Maisonette Shares Heating or Hot Water With Other Properties?

Some maisonettes in converted houses or larger residential buildings rely on shared heating or hot water arrangements. Others have their own independent systems.

If your property has shared equipment, explain how the system operates when arranging an EPC assessment. Make available any relevant information about the equipment serving your dwelling.

The assessor can then determine which details are relevant under the applicable methodology.

Do not assume that a shared heating system automatically improves or reduces your EPC rating. The outcome depends on the system’s characteristics and the other features of the property.

The same principle applies to renewable technologies. If your maisonette has access to a communal or individual battery storage system, our guide to EPC ratings for homes with battery storage in London explains why installing a battery alone does not guarantee a higher rating.

How Is an EPC for a Maisonette Different From an EPC for a Basement Flat?

Both property types can form part of a larger building, but their construction and position can differ considerably.

A basement maisonette may have rooms below ground level, whereas a maisonette arranged over the ground and first floors may have different exposed walls, windows and floor arrangements.

The correct assessment depends on the individual dwelling rather than the property label alone.

For a more specific explanation of below-ground accommodation, see our article on EPC for basement flats in London.

If you are buying a maisonette in a recently completed development instead, our new-build EPC guide covers the documentation and assessment considerations associated with newly constructed homes.

These related guides can help you identify which property-specific factors deserve attention before booking an assessment.

What Documents Should You Prepare Before an EPC Assessment?

Preparing the available information before your appointment can make the process more straightforward.

For a maisonette, consider gathering:

• Your existing EPC, if available.

• Records of insulation improvements.

• Heating system installation documents.

• Boiler, heat pump or heating control specifications.

• Hot water system information.

• Window replacement records.

• Solar panel or battery storage documentation, where applicable.

• Details of significant alterations or refurbishment.

Not every document will be necessary. The useful information depends on the property and the features installed.

If you have recently renovated the maisonette, explain which areas have changed and retain relevant records. This may help establish the property’s current characteristics.

You should also check that any existing certificate relates to the correct dwelling. A certificate for an entire building should not automatically be assumed to cover a separate self-contained maisonette.

How Can You Improve the EPC Rating of a Maisonette?

If your existing EPC includes recommendations, use them as a starting point for investigating possible improvements.

The most appropriate measures depend on the property’s condition, construction, heating system and budget.

Review the Insulation

Where insulation is inadequate, a suitable improvement may help reduce heat loss. However, the correct solution depends on the building’s construction and any restrictions that apply.

For example, insulation work in an older converted building may require a different approach from work in a modern purpose-built property.

Check the Heating Controls

Heating controls can help occupants manage indoor temperatures and heating schedules.

Before replacing equipment, make sure you understand the existing system and whether its controls are operating correctly. Ask a qualified professional to investigate technical problems.

Consider Heating Improvements Carefully

A replacement heating system may be worth investigating if the existing installation is inefficient or unsuitable.

However, a new boiler, heat pump or electric heating system does not guarantee a specific EPC band. Review the existing certificate and seek appropriate advice before committing to a major upgrade.

Read Your EPC Recommendations

An EPC includes recommendations tailored to the assessed property. These can help you identify areas worth investigating.

Our article on EPC recommendations explained explains how property owners can review potential improvements without assuming that every recommendation is equally suitable.

Remember that carrying out an improvement does not automatically mean you need a new EPC. Whether an updated certificate is appropriate depends on your circumstances and the requirements that apply.

What Should Landlords Check Before Renting Out a Maisonette?

Landlords should check the EPC early when preparing a maisonette for rent.

First, establish whether a valid certificate already exists and whether it covers the correct dwelling. Then review the property’s current rating and consider any applicable rental energy-efficiency requirements.

The requirements and exemptions can depend on the property’s circumstances, so consult current government guidance before making compliance decisions.

If the property has been empty during refurbishment, our guide to EPCs for empty properties in London explains why checking the certificate and other property information is an important part of preparing for a sale or rental.

You should also ensure that the property details used in your marketing materials match the current accommodation. Significant layout changes may require you to review the relevant documentation.

How to Arrange an EPC for a Maisonette in London

If you need an EPC, start by checking the existing certificate and confirming whether another assessment is necessary.

If a new certificate is required, provide accurate information about the property and arrange access to the relevant rooms and heating equipment.

You can learn more about arranging an assessment through our Residential EPC service in London.

If you are working to a tight property marketing deadline, you can also enquire about the Same Day EPC service. Appointment availability and turnaround times should be confirmed when booking.

Before the assessment, gather any available records of insulation, heating and other relevant improvements. This preparation can help the assessor establish the property’s characteristics.

Frequently Asked Questions

Does every maisonette need its own EPC?

A self-contained maisonette generally needs an EPC when sold or rented out, subject to applicable rules and exemptions. Check whether an existing certificate covers the correct dwelling before arranging another assessment.

Does a maisonette automatically receive a lower EPC rating than a house?

No. The rating depends on the property’s construction, insulation, heating, hot water and other relevant characteristics. The fact that a property is a maisonette does not determine its rating.

Can shared heating affect an EPC assessment?

Shared heating arrangements may be relevant to the assessment. The assessor needs to establish how the system serves the dwelling and which details apply under the relevant methodology.

Do I need a new EPC after renovating a maisonette?

Not necessarily. An EPC is generally valid for ten years unless replaced by a newer certificate. Renovation does not automatically require a new assessment, although the circumstances of a sale, rental or other transaction may affect what is needed.

Can I improve my maisonette’s EPC rating without replacing the heating system?

Potentially. Suitable insulation, heating controls and other property-specific measures may be worth investigating. The best options depend on the existing EPC recommendations and the property’s characteristics.

Final Thoughts

An EPC for a maisonette in London helps owners, landlords and prospective buyers understand the energy performance of an individual dwelling. Although maisonettes may share walls, roofs, floors or heating systems with other properties, their ratings depend on the characteristics of the accommodation being assessed.

Before arranging an EPC, check the existing certificate, gather relevant documents and make sure the assessor can establish the property’s construction and heating arrangements.

If you are considering energy-efficiency improvements, start with the recommendations on your current EPC and seek appropriate professional advice before undertaking major work.

For help arranging an assessment, visit Urgent EPC’s Residential EPC service in London.

Disclaimer: This article provides general information about Energy Performance Certificates. Requirements, exemptions and assessment outcomes depend on the property’s circumstances and the applicable methodology. Always check current official guidance before making property compliance decisions.