Home » What Cladding to Avoid?

What Cladding to Avoid?

Helpful resources

Introduction

Choosing the right cladding for a commercial building is crucial for safety, longevity, and appearance. With so many options on the market from exterior metal wall cladding sheets to composite panels, it’s important to know not just the best choices but also what cladding to avoid. In recent years, the spotlight has been on cladding materials due to high profile failures and safety concerns. This blog will explore which cladding materials are high risk or problematic, and how to make informed decisions for your project.

What cladding to avoid?

Commercial Cladding Prices vs Quality

Not all cladding offers the same level of safety. External commercial cladding must do more than protect a building from the weather, it must also meet strict fire and structural standards. In response to serious fire incidents, UK regulations now ban certain combustible materials, particularly aluminium composite panels with a polyethylene core. Other cladding such as untreated timber, some high pressure laminates and even uPVC can also pose risks by spreading flames or releasing toxic smoke.

Unsafe cladding is not just a fire risk. Older asbestos cement panels and poorly installed systems that loosen or fail over time can be hazardous to both occupants and the public.

To ensure safety, always choose cladding that has been tested and approved to meet UK building regulations and avoid any materials that have been highlighted as unsafe by industry experts.

Best Commercial Cladding Options vs Materials to Avoid

When planning a cladding project, it helps to know the best commercial cladding materials available – and which ones to avoid. Here’s a look at some recommended choices versus those that tend to cause problems:

  • Recommended (Best) Cladding Materials: Non-combustible and durable options are generally best. This includes metal cladding (like coated steel or aluminium panels) which is robust and often fire resistant. Fibre cement cladding boards are another top choice; they are made of cement mixed with fibres, so they don’t burn and require little maintenance. Quality insulated composite panels (for example, steel panels with mineral wool or high density foam cores) can provide excellent insulation and weather protection when properly fire rated. For a more natural look, treated timber cladding from sustainable sources can be used safely on low rise buildings, as long as it’s installed with fire breaks and maintained.

Cladding to Avoid: Steer clear of materials known for safety or durability issues.

  • Combustible cladding panels – such as aluminium composites with flammable cores or cheap plastic cladding are top of the list to avoid due to fire risk. Untreated steel sheeting should also be avoided; if steel panels lack proper galvanisation or protective coating, they will be prone to rust, leading to structural weakness and water ingress. As mentioned, any asbestos containing cladding (found in very old facilities) is hazardous and should not be used in any modern context. Be cautious with budget uPVC cladding as well: while inexpensive, thin PVC panels can crack, discolour, or even sag over time, especially on sun exposed elevations, and they offer poor fire resistance.

In summary, the best commercial cladding choices are those that are fire safe, weatherproof, and built to last. The materials to avoid are generally the opposite: flammable, prone to deterioration, or legacy products that no longer meet modern standards. By choosing wisely, you ensure the exterior of your building remains safe and sound for decades.

Commercial Cladding for Sheds

Commercial and industrial sheds need strong cladding that can withstand harsh weather. These buildings often protect valuable stock or equipment, so they should be treated with the same care as any commercial property. Avoid using domestic grade panels, plastic sheets, bitumen panels or interior boards because they deteriorate quickly and fail under strong weather conditions.

The best options are materials designed for external use such as galvanised or coated steel or aluminium sheets, insulated composite panels and fibre cement sheets. These materials are durable, resistant to rot and fire and help prevent leaks or condensation. Investing in good quality cladding ensures that the shed remains weatherproof, secure and long lasting.

Exterior Metal Wall Cladding Sheets

Exterior metal wall cladding sheets are very popular in industrial and commercial construction because they are strong, durable and give a clean modern look. Steel and aluminium panels are low maintenance and can be coated in different colours to enhance the building’s appearance.

To make the most of metal cladding it is important to avoid common mistakes. Never use bare or untreated metal sheets on external walls because plain steel will rust when exposed to moisture. Always choose galvanised steel or aluminium with a protective finish such as polyester paint or plastisol. Cheap uncoated metal will quickly rust and deteriorate.

Poor installation is another major risk. Metal cladding panels must be overlapped correctly and fixed with the right screws and washers to prevent leaks. Mixing different metals, such as ordinary steel fixings on aluminium panels, can cause corrosion. Expansion and contraction due to temperature changes also need to be considered. Very long panels without expansion joints can buckle or become loose over time.

Summary

Roofing and wall cladding should be treated as one complete system in commercial and industrial buildings. Both usually use similar materials such as profile metal sheets or insulated composite panels. The same quality standards must be applied to both areas because a building is only as weatherproof as its weakest point.

Choosing high quality materials for the roof but poor quality cladding for the walls, or the other way around, creates risks such as leaks, heat loss and safety hazards. The roof and walls should be non combustible if regulations require it, resistant to corrosion and suitable for the site conditions. For example, coastal sites need marine grade coatings, and insulated panels are best where thermal performance is important.

Frequently Asked Questions (FAQs)

High risk cladding is any material that poses a serious fire danger or is likely to fail in safety performance. A common example is aluminium composite panels with a polyethylene core, which are highly combustible and have been linked to major fire incidents. Other high risk materials include high pressure laminate panels that are not fire treated and timber cladding that has not been treated to resist fire, as both can allow flames to spread quickly on the exterior of a building. Even uPVC cladding can be considered high risk because it is plastic, burns easily and releases toxic smoke.

Unsafe cladding refers to cladding systems that create a risk to the safety of people in and around a building. This often means materials that can catch fire and spread flames on the exterior, which has been a major issue in the UK and has led to large scale investigations and replacement programmes. Unsafe cladding can also include panels that are loose, likely to fall or that let water into the structure, causing damage over time. Any cladding that could fuel a fire, produce harmful smoke or fail structurally is considered unsafe and should be replaced with materials that meet current safety standards.

Cladding leaks are usually caused by poor system design or installation rather than the cladding material itself. Some systems are more prone to leaks than others. Solid cladding systems with no joints, such as continuous rendered foam or plaster, can leak if there are cracks or gaps, and they often do not have a ventilated cavity to let moisture escape.

Rain screen cladding systems, which include an air gap and drainage layer, are less likely to leak because they are designed to manage water that gets behind the surface. Overlapping sheet systems, such as simple timber boards or lightweight panels, can leak if the overlaps are too small or the boards warp. Metal sheet cladding can also leak at joints or screw fixings if these areas are not sealed correctly.

uPVC cladding is a lightweight plastic option that is easy to fit and inexpensive, which makes it popular for small buildings or simple refurbishments. However, it is less durable, can fade in sunlight, become brittle with age and will burn and melt in a fire.

Composite cladding is made from a mix of materials, such as fibre cement or wood and plastic blends. These boards are stronger, more stable and longer lasting. Fibre cement composites are rot proof and non combustible, while wood plastic composites resist rot and often include additives to improve fire performance.

Overall, composite cladding is the better choice for strength, longevity and fire safety, making it the preferred option for commercial buildings. uPVC is mainly suited to small projects with limited budgets where performance is less critical.

Get In Touch

At RDP Cladding, we offer high quality roof light solutions, including new installations, refurbishments, and replacements, tailored to your building’s specific needs. Get in touch today to explore how roof lights can improve your energy efficiency.

We can help you

Commercial Cladding & Roofing

Looking to enhance your building’s durability, energy efficiency, or weather protection? At RDP Cladding, we specialise in high quality cladding, roofing, and guttering solutions tailored to your needs.

Do you have a project requirement?