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timber and steel exterior cladding on a barn in Norwich

Exterior cladding: a buyer’s guide

From slate tiles to zinc panels, which is the best option for your home?

By Andrea Manley | 11 August 2022

Cladding forms the protective external layer of a property, and the choice of material will dictate the finished look. There’s an array of different exterior cladding types and materials to choose from, including timber shingles, metal sheeting, stone tiles and composite boards.

Teaming contrasting types such as timber with render or zinc is a great way to highlight architectural details or define a standout extension.

When teamed with insulation, cladding helps to improve the thermal performance of a building. Prices vary between materials, and installation will add to the final cost. Although some options can be fitted by a competent DIY-er, most will require installation by a professional.

Corten external cladding on a residential property in Lewes

Corten exterior cladding on a riverbank home in Lewes. Photo: Matt Chisnall

Will you need planning permission?

There are instances when work on the outside of your home comes under permitted development rights (PDR), such as if you are replacing worn-out cladding like for like. The exception is if you live in a conservation area, a national park, or an Area of Outstanding Natural Beauty (AONB), when you’ll need to apply for planning permission.

Those building a new home must include details of the cladding when making a planning application. In some cases, the type of material that can be used will be dictated by the planners to suit the area or neighbouring properties. Check with your local authority before starting any work. For more information, visit the Planning Portal.

Cladding and fire safety

The fire performance of any cladding system must be compliant with Building Regulations. It’s important to investigate a product’s fire rating, seek information from the manufacturer and ask about warranties. It must also be installed correctly.

The Euroclass system for fire classification is being adopted over the older British Standards. It ranges from A1, which means non-combustible and makes no contribution to fire, down to F, which means combustible and easily flammable. Click here for more detailed fire safety advice from Gary Peacey, director at EWI Consultants.

timber and steel exterior cladding on a barn in Norwich

This converted agricultural building in Norfolk, designed by 31/44 architects, is clad in pastel-coloured corrugated steel from Joris Ide and vertical timber louvres from Russwood. Photo: Nick Dearden

Timber cladding

Timber cladding is either softwood, hardwood or modified wood. It’s available as shingles, which look more like timber tiles, or planks in varying sizes that can be fixed horizontally or vertically. Wood that is naturally knot-free (clear grade) brings a clean, contemporary look, while knottier varieties have a more rustic appeal.

Durable softwood species such as western red cedar, European larch and Douglas fir resist moisture and decay. When left untreated they will weather to a silvery grey, or they can be given a surface treatment, which needs to be repeated periodically, to preserve their original colour.

Larch is a commonly used softwood as it contains a natural protective resin, making it resistant to rot and decay. Western red cedar contains natural oils that act as preservatives to give the wood exceptional durability which, combined with its tendency to lie flat and remain straight in service, makes it particularly well-suited for cladding.

Larch wood cladding on an R2F house on the Isle of Skye

The R2F house, designed and built by Rural House on the Isle of Skye, is clad with larch from the Scottish Highlands. Photo: Rural Design

Hardwoods such as oak and sweet chestnut are even more durable than softwoods. The boards are generally air- or kiln-dried to a moisture content between 15% and 25% for structural stability, and come with a rustic waney edge where the bark is retained or more clean-lined machine-cut finishes.

Modified woods such as Abodo, Accoya, Kebony and ThermoWood are softwoods that have been thermally or chemically altered to enhance their stability and durability. They’re virtually maintenance free, with a lifespan of 50-60 years, and are widely used as exterior cladding.

Yakisugi timber is charred to waterproof and preserve the wood, making it resistant to fire, rot, insects and the effects of sunlight. There are several shades available, ranging from pale grey/ brown to black. It’s expensive but it requires no maintenance.

Costs for timber cladding vary. Expect to pay from around £40 per sqm for softwoods, £90 per sqm for hardwoods, and £80 per sqm for modified timber, while yakisugi ban costs around £100 per sqm.

Look for a product that’s sustainably sourced, such as those with FSC certification, has the CladMark quality assurance guarantee from the Timber Decking and Cladding Association CladMark, and a guarantee of at least 25 years.

Read more: 5 timber cladding ideas from Grand Designs

Shou Sugi Ban exterior wood cladding on a kitchen extension

An extension wrapped in charred yakisugi wood cladding from Kebony. Photo: Adelina Lliev

Composite cladding

Fibre cement board resembles painted timber. Made from cellulose, fillers, fibres and cement, it comes as panels or planks that can be painted or have a coloured pigment added during manufacturing. This makes scuffs and scratches less visible. It offers a lightweight facade that allows for shorter construction times and improved thermal performance, as well as long-term colour stability.

Planks can be attached to vertical battens, ensuring that the horizontal joins overlap to encourage water run-off. The panels have a fitting system with concealed screws for a sleek finish. Fibre cement board costs around £150 per sqm with installation and can last up to 60 years. Composite products such as Teckwood’s are made from recycled plastics and timber. Millboard’s cladding is made from polyurethane resin reinforced with mineral stone. Both are low maintenance, costing around £110 per sqm.

Read more: 5 stunning house exterior transformations

Gloucesterhsire farmhouse with new extension named house of the year 2021

Alison Brooks Architects’ award-winning extension in Gloucestershire is clad in fibre cement board to help distinguish it from the original Georgian farmhouse. Photo: Paul Riddle

Stone and brick cladding

Stone cladding finishes are varied, ranging from split-face tiles that create a multifaceted texture to completely smooth surfaces. Stone cladding is attractive and longlasting, but it can be heavy to work with and is prone to frost damage.

Limestone, slate, sandstone and granite come in thin tiles or slips that are virtually indistinguishable from full thickness stone and lightweight enough to be fixed with adhesive. Modular flat panel systems are cost effective and quick to install.

Though durable, stone will weather over time. Sealing isn’t a necessity, but it does offer extra protection from weathering. Select local suppliers to limit the eco impact of transportation. Limestone costs from £170 per sqm, slate from £120 per sqm and sandstone from £73 per sqm.

Read more: Nineteenth century stone barn conversion

Basalt stone walls on a country house in Northern Ireland, by 2020 Architects

2020 Architects used Basalt for the walls of this five-bedroom country house in Northern Ireland

Metal cladding

Aluminium, copper, steel, Corten steel and zinc sheets or panels are low maintenance, long lasting and recyclable. Metal cladding offers a contemporary look and can be shaped to follow curved exteriors. It comes in large sheets, prefabricated off-site or as shingles, which are smaller and easy to handle. Finishes can be brushed, sandblasted or mirrored, as well as powder coated.

Steel can be powder-coated in any RAL colour or galvanised and should perform well for around 35 years. Corten steel is a maintenance-free weathering steel that develops a rusty patina; however, discoloured rainwater run-off can be a problem. Lightweight aluminium cladding will last around 40 years, while copper develops a verdigris patina, and has a lifespan of around 100 years. Copper alloys have a gold/bronze finish if treated.

Zinc is pricey, but will perform well for up to 60 years, so it’s economical over its lifespan. It has a silvery finish when first installed, which weathers to look like lead when left untreated. It can also be treated to speed up this weathering process. Expect to pay from £50 per sqm for steel, £70 per sqm for aluminium, and £150 per sqm for zinc. At £250 per sqm, copper is the most expensive.

Read more: Rugged Angus countryside inspires Zinc-clad home

The Corten steel cladding on this self-build in Lewes has a rusty red patina

The Corten steel cladding on this self-build in Lewes has a rusty red patina. Photo: Matt Chisnall