Christchurch architect Cymon Allfrey discusses claddings and how they enhance the space and forms of a design.
Architecturally, exterior cladding is the personality of your building; it is the skin which makes your home unique so it is important you are selecting a material which not only will age gracefully with the building but set the scene architecturally of what lies beneath.
Enhancing the geometry of the form, cladding can bring a sense of colour and texture to the design, and tells the story and history of your home.
One of the most exciting things about cladding is that it offers passers-by, and of course you, the opportunity to experience the building in different ways. From your street front, the architectural language and depth of your cladding material are very different to the experience you have up-close when the tactile surface reveals itself.
It is through cladding that we can enhance the spaces and forms of the design. Be this through the coupling of materials, such as concrete and timber, the use of an applied finish or the balance of light and dark – through the use of colour or natural light rays and how shade plays out across the building.
This push and pull of light and dark can be particularly relevant, for example when blending a dominant garage door into the design – a lighter contrasting cladding positioned alongside will then draw the eye away from the garage door creating a friendly street appearance.
The primary consideration when it comes to selecting a cladding material is that you must be deliberate – understand why you are using the material. Your cladding choice should enhance the flow of the design ultimately enhancing the architectural response to the building.
From industrial to modern, domestic or utilitarian – think about what look you want to achieve, what the purpose of the building is and how you can use cladding to tell a story.
Through the exploration of a love of modernism, concrete has become a popular material choice for the exterior of the buildings I have designed – despite it not being a cladding material in the traditional sense of the word.
It's honest and raw qualities were appealing, along of course with its simple modern look. Typically used where forms are bold and strong, it is a material which will age gracefully with the building. Paired with cedar battens, concrete can be softened for domestic use, or left as a raw material for an industrial feel.
Like all materials, there are pros and cons to using concrete – the most notable being you never know what you are going to get until it is out of its pre-cast mould, so flexibility around imperfections is ideal; however you can cover most with an applied finish such as a stain or paint.
Your end result with concrete will be durable, raw, geometric and in some instances brutal.
Timber is an incredibly versatile cladding material and can be used in a variety of ways – from painted weatherboard to vertical cedar slats, the limit is simply what look you want to achieve; from historical to modern, timber is an option.
Timber generally has a 7-10 year maintenance cycle and as an organic product is prone to movement so it pays to bear this in mind. Timber is a material which is not only familiar but comfortable, so the end result is often a domestic architectural language.
Brick embodies notions of simple forms, familiarity and respect. The use of this material offers its end user a product which is robust, low maintenance and safe – seismic events of late to the side.
Brick was one of the original cavity construction materials and was decades ahead of our understanding around the risks of weather-tightness. Throughout the decades brick and masonry have remained consistent and their ready availability has seen them firmly mortar a place in New Zealand’s architectural language.
As technologies and fashions have advanced there has been some shift in their popularity, however, brick will forever have a place in New Zealand’s architecture. It is a material we all know, appreciate and recognise.
The use of metal as a cladding material is an interesting one. With sheets of corrugated iron conjuring notions of the quintessential Kiwi utility shed, the use of this material will bring a sense of utilitarian familiarity to your building.
The advancements and refinements of metals over the years now allow us to achieve this familiarity with a contemporary aesthetic and has seen metals be applied to architectural forms at both the higher and lower ends of the scale.
This particular cladding material, coupled with the evolution of zinc cladding, has seen a shift in the architectural sector in the approach to roof lines, as sheet metal allows the boundaries to blur between a defined roofline and exterior walls, creating an interesting dynamic of forms.
From schist to Oamaru stone, granite or slate, New Zealand offers homebuilders an extensive range of natural stone claddings.
While there have been a number of debates around the sustainable nature of stone it is important to note that while it is not a renewable resource it is one of the only exterior claddings on the market which can be re-used – a notion which currently is being played out in Canterbury.
Depending on the effect you wish to create there are a number of finishes which can be applied to the stone – fractured slate is commonly used as a feature cladding adding texture to the building and complementing a primary cladding; while polished basalt can be used in clean sheets to achieve a very different effect.
Of all the cladding materials on the market stone is the one material commonly also used in the interior of the home – be it as a feature wall, fire surround or kitchen benchtop.
Plastering systems have been around for centuries providing a seamless appearance. Modern plaster or Stucco systems have reinforced Modified Cement-based plasters that are applied to a variety of substrates.
Traditionally Stucco is applied over brick, masonry block, fibre-cement or plywood sheeting which is then painted. This traditional method of plastering has been used in New Zealand since the 1920s.
There are various modern plastering systems available in the market which, when applied over timber or steel framing are installed over a drainage cavity like most other exterior claddings which aids in protecting the structure from incidental moisture should it occur.
All external plaster claddings are required to be installed by Licensed Building Practitioners - plastering license class.
Modern plastering systems include window flashing suites, with various hand-applied layers of plaster and reinforcement, finished with acrylic textures, or paint systems. The plastering and flashing systems vary slightly between systems, yet must comply with building code requirements.
The main change that occurs with the systems is generally the substrate to which they can be applied. The various substrates or backings can include brick, block, insulation board, AAC concrete or fibre cement. Each substrate provides unique benefits, such and thermal insulation, or impact resistance dependent on the location, or intended use.
As with all exterior cladding, plaster is no different in that it requires general maintenance such as painting, and cleaning. Plaster is a relatively easy surface to paint due to its flat surface, which also allows you the flexibility to change the colour easily if required.