Choosing Your Exterior Finish
The exterior finish of your building is one of the most important design decisions you’ll make. It defines the character, kerb appeal and first impression of your property. It also needs to perform — protecting the building envelope from weather, UV radiation and temperature extremes for decades.
In this guide, we compare four popular exterior finishing options honestly, covering the genuine pros and cons of each. As a timber merchant, we obviously believe in the superiority of natural wood — but we’ll let the facts speak for themselves.
Natural Timber Cladding
The Case For
- Unmatched natural beauty: No manufactured material can replicate the warmth, texture and grain variation of real wood. Each board is unique, creating depth and character that simply cannot be faked.
- Sustainability champion: Timber is renewable, carbon-storing and biodegradable. A timber-clad building has a significantly lower carbon footprint than one clad in any manufactured material.
- Versatility: Available in dozens of species, profiles, finishes and colours. Can be installed horizontally, vertically or diagonally. Works on contemporary and traditional buildings alike.
- Repairability: Individual boards can be replaced without disturbing the rest of the installation. No colour-matching issues as with render or composite panels.
- Improves with age: Whether oiled to maintain its original colour or allowed to silver naturally, timber cladding develops character over time. Many would argue it looks better at 10 years than at day one.
- Thermal performance: Wood is a natural insulator. Timber cladding with a ventilated cavity provides excellent thermal buffering, reducing heating and cooling costs.
The Case Against
- Maintenance: Timber cladding does require periodic maintenance — typically re-oiling every 3-5 years if you want to maintain a specific colour. Left untreated, it weathers but needs no maintenance at all.
- Variable weathering: Different elevations weather at different rates, which some find inconsistent (others find charming).
- Fire rating: Untreated timber doesn’t meet the highest fire ratings required for some applications, particularly tall buildings post-Grenfell. Fire-retardant treatments are available but add cost.
Composite Cladding
Composite cladding boards are manufactured from a mix of wood fibres (or wood flour) and plastic polymers (typically PVC or polyethylene), formed into boards that mimic the appearance of natural wood.
The Case For
- Low maintenance: The primary selling point. Composite boards don’t need oiling, staining or painting. A periodic wash is all that’s required.
- Consistent appearance: Every board looks the same — beneficial if you want absolute uniformity.
- Rot proof: The plastic content means composites don’t rot, though they can develop mould and algae on the surface.
The Case Against
- Appearance: Despite manufacturers’ claims, composite cladding does not look like real wood. The repeating patterns, uniform colour and plastic sheen are identifiable at a glance. Close up, the difference is obvious.
- Environmental impact: Composites are made with virgin or recycled plastic and require significant energy to manufacture. They are not biodegradable and are difficult to recycle at end of life.
- Thermal expansion: Composite boards expand and contract significantly more than timber with temperature changes. This requires careful allowance during installation and can cause buckling in extreme heat.
- Fading: Despite UV stabilisers, most composites fade noticeably over 5-10 years, particularly darker colours. Once faded, the colour cannot be restored.
- Heat retention: Dark composite boards in direct sunlight can become uncomfortably hot — a real issue for south-facing walls and decking.
- Cost: Mid-range composite cladding is comparable in price to premium softwood timber cladding, but lacks the natural beauty and environmental credentials.
- Non-repairable: If a composite board is damaged, finding an exact colour match from the same batch can be impossible, especially after years of UV fading.
Render Systems
Modern render systems (typically polymer-modified or silicone renders applied over insulation boards) provide a smooth, uniform exterior finish available in a wide range of colours.
The Case For
- Clean, contemporary aesthetic: Render provides the smooth, minimalist look that many modern architectural designs call for.
- Good insulation: External wall insulation (EWI) systems with a render finish can dramatically improve a building’s thermal performance.
- Colour range: Available in virtually any colour with no need for painting.
- Self-cleaning options: Some premium silicone renders have hydrophobic properties that help keep the surface clean.
The Case Against
- Cracking: All render systems are prone to cracking over time, particularly at stress points around windows, doors and building movement joints. Cracks allow water ingress behind the render, which can cause serious hidden damage.
- Algae and staining: North-facing and shaded rendered walls are magnets for green algae growth. Regular cleaning or biocide application is needed.
- Impact damage: Render is vulnerable to impact damage from ladders, footballs, garden equipment and general wear. Repairs are visible and colour matching is difficult.
- Not breathable (some systems): Cement-based renders can trap moisture within the wall, leading to damp problems in older buildings. Only modern breathable renders (lime or silicone) are suitable for solid-walled properties.
Traditional Brick
The Case For
- Proven longevity: Well-built brick walls last 100+ years with minimal maintenance.
- Zero maintenance: Brick needs no painting, oiling, rendering or cleaning.
- Familiar and accepted: Brick is the default exterior material in much of the UK, meaning it blends seamlessly with existing streetscapes.
- Thermal mass: Brick walls absorb and slowly release heat, helping to moderate indoor temperatures.
The Case Against
- Aesthetically limited: Brick provides a single texture and limited colour range. It cannot achieve the contemporary, warm or dramatic aesthetics that timber, render or metal can.
- High embodied carbon: Brick manufacturing is energy-intensive, involving firing clay at over 1,000°C. The carbon footprint per square metre is significantly higher than timber.
- Cost: Full brick construction is one of the most expensive exterior options when labour costs are included.
- Inflexible: Adding brick to an existing building is rarely practical. It’s essentially a new-build-only option.
The Bottom Line
Every material has its place, and the best choice depends on your project, budget and priorities. However, for the combination of beauty, sustainability, versatility and character, natural timber cladding is hard to beat.
At Timberulove, we supply timber cladding in over 15 species and dozens of profiles, with expert advice and next-day delivery. Whether you’re cladding a single feature wall or an entire building, we’re here to help.
Browse our full cladding range or contact us for samples, pricing and project advice.