From striking architectural statements to critical elements of energy performance and fire safety, façades play a vital role throughout the lifecycle of buildings. 

Despite this, many professionals operating in the built environment lack a solid understanding of the different types of façade systems currently in use, the advantages and disadvantages of these systems, their common defects, and the importance of a robust inspection and maintenance regime. 

At Watts Group, our role as building surveyors often places us on the front line when façade failures occur - many of which could be prevented through more informed decision making during the design, procurement and construction stages, regular inspection and maintenance, and a deeper understanding of façade design principles and defects. 

What Is a Façade - and Why Does It Matter?

In the simplest terms, a façade is the outer skin of a building. It forms the weatherproof envelope, contributes to fire performance, impacts a building’s EPC rating and sustainability criteria, and influences thermal and acoustic comfort for occupants. Aesthetically, the façade shapes first impressions as the principal front of a building - but it is much more than a visual device. Façades are the first line of defence between the external environment and interior of a building, they must endure thermal movement, weather exposure, and time.

Critically, façades can account for up to 35% of the overall construction cost of a building, with factors such as complexity, materials, and overall project size influencing costs. Yet despite their importance, they are also an area most prone to failure.

Common Façade Systems in the UK

In this article, we focus on three types of façades commonly encountered in the UK Built Environment: Traditional brickwork, curtain walling, and rainscreen cladding. 

  1. 1. Traditional Brickwork

    Brick masonry has been used for centuries in the UK due to its high durability and can last decades when properly constructed and maintained. It provides resistance to fire and infestation, offers good acoustic performance, and is generally considered to be low maintenance with repairs typically required at wider intervals. However, brickwork can be time-consuming to construct, is porous which can lead to damp issues in older properties and is susceptible to cracking due to its poor tensile strength.

  2. 2. Curtain Walling (Unitised and Stick Systems)

    Curtain walling can be categorised into either unitised or stick systems. Both forms of construction are non-structural with imposed loads such as wind transferred into the primary structure of the building. Due to a wide range of materials and design options, curtain walling is a popular choice of construction seen frequently on commercial buildings.

    Unitised systems are formed of prefabricated panels manufactured off site, offering enhanced thermal, acoustic, and weather performance. They are typically quicker to install on site and can incorporate structural movement and fire resistance during the design and manufacturing process.

    Stick systems are constructed on site, formed of individual components known as mullions and transoms with glazing panels installed into these components. This form of curtain walling offers flexibility, lower upfront costs and is generally easier to maintain. However, both forms of curtain walling are expensive and sensitive to workmanship quality.

  3. 3. Rainscreen Cladding

    Rainscreen cladding is a modern, lightweight system offering quicker installation than traditional methods of construction. This form of façade offers ventilation and moisture control through an air cavity, can enhance thermal performance, and depending on choice of materials can be low maintenance. However, these systems are expensive, require increased design, detailing and planning, and have only become popular in recent decades resulting in less data on their long-term weaknesses.

    Each system has its own design life and performance expectations, with elements like gaskets, seals and double-glazed units requiring earlier maintenance or replacement. 

Common Defects: What to Look Out For

Watts surveyors commonly encounter the following façade defects:

Traditional Brickwork

    • External cracks caused by a variety of reasons such as thermal movement, structural settlement, subsidence, heave, and cavity wall tie failure.
    • Spalling brickwork caused by freeze-thaw cycles.  
    • Mortar deterioration caused by weather exposure, freeze-thaw cycles, erosion, structural movement, incorrect construction, and natural ageing.

Curtain Walling 

    • Water ingress caused by a variety of issues such as poor installation and detailing of sealant and weatherstrips, blocked drainage channels, improper maintenance, defective materials and environmental factors which accelerate ageing.  
    • Shrunken and dislodged gaskets due to age, improper maintenance and weather exposure.
    • Dislodged caps to mullions and transoms due to improper installation and thermal expansion.  

Rainscreen Cladding

    • Missing or insufficient cavity barriers resulting in fire safety hazards.
    • Distortion of High-Pressure Laminate (HPL) panels due to incorrect fixing detailing which does not allow for natural thermal movement.
    • A lack of drainage and ventilation provisions within the systems cavity including blocked drainage which can result in water ingress and moisture issues.

These issues not only compromise building performance and appearance but can also result in significant safety hazards and financial liability.

Inspection & Maintenance: Setting the Standard

Why is undertaking routine inspections of a building’s façade so important?

There are a variety of reasons including early detection of issues, enhanced health and safety, reduction in costs to address more significant issues that may result from a lack of early action, increasing longevity of the façade, and maintaining a buildings value and aesthetics. 


How often should inspections be undertaken?

The British Standards Institute (BSI) released BS 8210 which outlines the best practice for façade inspections, recommending a tiered approach:

Routine: Routine inspections should be undertaken throughout the annual period to determine whether specialist inspections are required. This approach will help identify defects as early as possible and allow intervention before more serious issues arise. 

Annual: General, non-intrusive inspections should be undertaken on an annual basis. This could be as part of an annual Planned Preventative Maintenance (PPM) survey or general building condition assessments. These should be undertaken by qualified, experienced professionals who will be able to identify defects and provide a remediation methodology. 

Detailed: Detailed inspections should be undertaken no less than once every 3 years. These should be undertaken by specialist persons who are experienced in assessing the façade in question. More intrusive inspections may be involved, such as removing a rainscreen cladding panel to assess the non-visual elements of the façade, such as the support structure and fire stopping.

Best Practice Procurement

From initial investigation to completion, the success of façade repair projects is influenced during the pre-commencement stage. Our best practice recommendations include:

  1. 1. Thorough Investigation – Understanding the scope of investigations required and conducting those investigations to determine the root cause of the issue before specifying a repair methodology to avoid a trial-and-error approach.

  2. 2. Robust Documentation – Clarity and completeness of technical specifications and documentation is non-negotiable. A successful project should see good quality workmanship addressing the issues correctly, on time and on budget, and a well-prepared and robust pack of construction documentation is key to achieving that.

  3. 3. Competent Tendering – Vet contractors for financial stability, relevant experience, and workmanship quality. The contractors should be experienced in working on the type of façade you have, have a good reputation, and be able to demonstrate their understanding and suitability for the project.

  4. 4. Formal Appointment – Use recognised forms of contract and ensure requirements for any warranties and guarantees are defined. Suites of contracts such as JCT are designed to ensure there is a clear contractual agreement between both parties. Standard forms of contract without amendments are preferable, but in practice this isn’t always adopted. It is therefore important that both your professional and legal teams review any schedules of amendments to ensure you are not exposed to unnecessary risk.

  5. 5. On-Site Oversight – Regular site inspections and monitoring aligned with construction milestones are vital to ensuring design intent is carried through to installation. Poor workmanship can be quickly concealed during the construction process, and unless it’s spotted at this stage, it may not be apparent until a defect arises at a later date. 

  6. 6. Comprehensive Handover – Ensure a detailed completion pack is provided before practical completion is awarded. This should include at minimum receipt of all statutory, regulatory or other relevant consents and certification, comprehensive O&Ms, guarantees and warranties which should be fully executed, design conformity statements if requested, and a Health and Safety file. 

Ultimately, façades are too important - financially, functionally and reputationally - to be treated as passive features. With regulatory, environmental and safety expectations rising, a proactive approach to façade management is no longer optional.

Whether you manage a historic brick block or a newly clad high-rise, your role in safeguarding façades begins with understanding them. At Watts, we’re committed to supporting clients with the technical insight, inspection strategy and project management expertise to ensure their buildings stand strong for decades to come.

Dan Snape BSc (Hons) MRICS
Associate Director
+44 (0)7593382909
dan.snape@watts.co.uk