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Do Replacement Windows Need Building Regulations Approval?

 

Building Regulations have applied to replacement windows and external doors in England since April 2002. This generally applies when the complete window, including its frame, is being replaced.

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There are two main ways to demonstrate compliance:

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1. Use an installer registered with an authorised Competent Person Scheme.

2. Arrange approval through Building Control.

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A registered installer can self-certify qualifying replacement window work and notify the local authority after installation. Government-authorised schemes covering replacement windows include FENSA, CERTASS, NAPIT, Certsure, ASSURE and Blue Flame Certification.

Where the installer is not registered with an appropriate scheme, a Building Regulations application must normally be made before the windows are installed.

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What Do the Building Regulations Cover?

 

The exact requirements will depend on the property, window position and nature of the work. However, replacement windows and Building Regulations commonly involve the following areas.

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Energy efficiency

Replacement windows must achieve the required level of thermal performance. The installer should supply windows with suitable energy-efficiency specifications and install them without unnecessary gaps or heat loss around the frames.

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Ventilation

Windows can form an important part of the property’s ventilation system. Replacing older windows with more airtight units must not leave rooms without adequate background ventilation.

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Where existing windows contain background ventilators, such as trickle vents, suitable ventilation will usually need to be retained or provided in the replacements. Homeowners cannot avoid the ventilation requirements by signing a disclaimer or promising to add ventilation later.

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Safety glazing

Safety glass may be required in locations where there is a greater risk of someone falling against the glazing. This can include low-level windows and glazing close to doors.

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Depending on the position, toughened or laminated safety glass may be needed to reduce the risk of injury if the pane is struck or broken. Approved Document K provides the relevant guidance for protection from collision and impact.

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Means of escape

Some bedroom and habitable-room windows provide an emergency escape route. A replacement window should not make the existing means of escape less satisfactory.

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The opening size, clear opening area and position of the window may therefore need to be considered before changing its style or opening arrangement.

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Structural support

The installer should check that the wall above the window is adequately supported. This is particularly important when replacing older windows that may previously have helped support the brickwork.

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Bay windows require special attention because the window frames can form part of the support beneath the roof or upper structure. Structural posts, reinforced frames or other support may be required.

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Protection from falling

Where windows are positioned at a low level above an upper-floor surface, suitable guarding or restricted opening may be necessary to reduce the danger of falling.

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FENSA and Replacement Windows

 

FENSA is a government-authorised Competent Person Scheme for qualifying replacement windows and doors.

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A FENSA-approved installer can self-certify its installation instead of arranging a separate Building Control inspection. The completed work is registered with the local authority, and the homeowner receives a FENSA certificate as evidence of compliance.

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FENSA generally covers replacement external windows, doors, roof windows and rooflights in existing homes. It does not cover every type of glazing work, including windows in new-build properties, new extensions, new conservatories or repairs where the existing frame is retained.

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A FENSA certificate confirms Building Regulations registration. It is not the same as the installer’s product or workmanship guarantee.

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What Is a FENSA Replacement Certificate?

 

A FENSA replacement certificate is a replacement copy of a certificate previously issued for a registered installation.

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Homeowners sometimes discover that the original document is missing when preparing to sell or remortgage their property. A replacement can be ordered from FENSA where the installation was completed and correctly registered by a FENSA-approved installer.

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The certificate provides evidence that:

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• The installation was registered with the local authority

• The installer declared that the work complied with Building Regulations

• Energy-efficient products were used

• The work was completed through the FENSA scheme

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A replacement certificate cannot normally be obtained for work that was never registered with FENSA. It is also unavailable where the installation was certified through another scheme or approved directly by Building Control.

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What Happens If There Is No FENSA Certificate?

 

The absence of a FENSA certificate does not automatically mean that the windows fail to comply.

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The installation may have been:

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• Certified through another Competent Person Scheme

• Inspected and approved directly by Building Control

• Completed before the certification requirements applied

• Limited to glass replacement or repair work

• Installed without being properly registered

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First check whether another compliance certificate or Building Control completion document is available.

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Where qualifying replacement windows were installed without certification, the local authority or a registered building control approver should be contacted for advice. It may be possible to apply for retrospective approval, although inspections, supporting information and remedial work could be required.

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Building Control for Replacement Windows

 

A Building Control window replacement application will normally be needed when the installer is not authorised to self-certify the work.

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Building Control may consider:

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• The window specification

• Thermal performance

• Safety glazing

• Ventilation

• Emergency escape provisions

• Support above the opening

• Weatherproofing

• Protection from falling

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The application should be arranged before installation starts. A Building Control fee will usually be payable, and the work may need to be inspected before a completion certificate is issued.

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Using a Competent Person Scheme installer avoids the need for the homeowner to make a separate application for qualifying replacement work.

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Does Replacing the Glass Require Approval?

 

Replacing a broken pane or failed double glazed unit within an existing frame is generally treated as a repair rather than complete window replacement.

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Building Regulations approval is not normally required when:

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• Broken glass is replaced

• A misted sealed unit is changed

• A damaged sash is repaired

• Handles, hinges or locks are replaced

• Parts of an existing frame are repaired

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However, the replacement glass must still be appropriate for its location. Safety glazing may be necessary where the pane is close to floor level, alongside a door or in another critical position.

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Building Regulations for New Windows

 

Installing a completely new window is different from replacing a window within an existing opening.

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Creating a new opening can affect the structure of the wall and will normally require Building Regulations approval. The work may involve:

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• Designing and installing a suitable lintel

• Supporting the wall during construction

• Checking insulation around the opening

• Providing suitable ventilation

• Installing safety glass where required

• Considering means of escape

• Protecting privacy and preventing falls

• Weatherproofing the new opening

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A new window installed as part of an extension, loft conversion or wider building project should normally be included within the Building Regulations application for that work.

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FENSA certification generally relates to qualifying replacement installations and should not be assumed to cover windows in a new extension or newly created opening.

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Planning Permission and Building Regulations

 

Planning permission and Building Regulations are separate systems.

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Planning considers matters such as the external appearance of the property, overlooking and the effect on the surrounding area. Building Regulations deal mainly with construction, energy efficiency, ventilation and safety.

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A project may require:

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• Building Regulations approval but not planning permission

• Planning permission but separate Building Regulations approval

• Both forms of approval

• Neither, depending on the work

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Additional controls may apply to flats, listed buildings, conservation areas and properties affected by an Article 4 Direction.

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Documents to Keep After Installation

 

When replacement windows are completed, retain:

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• The FENSA or other scheme certificate

• The Building Control completion certificate, where applicable

• The installer’s invoice

• Product and workmanship guarantees

• Insurance-backed guarantee documents

• Window energy-performance information

• Maintenance instructions

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These documents provide evidence that the work was properly registered and may be requested by a solicitor or buyer when the property is sold.

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Find Trusted Window Installers

 

Correct installation is essential to ensure that replacement and new windows satisfy the relevant standards for energy efficiency, ventilation, safety and structural support.

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APN Double Glazing can connect homeowners with experienced local installers who can explain the certification route and arrange compliant window installation.

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Get in touch for expert advice and a free, no-obligation quote for your replacement or new windows.

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