Opening the envelope

Simon Wild of Formica group discusses how the application of cladding using traditional building methods has evolved, and explores the modern materials now on offer.

Traditionally, housebuilding techniques in the UK relied upon the use of local materials typical of the region, with selection echoing the surrounding geological formations and environment in which they were built. Homes constructed near forested areas would use timber, in clay regions bricks would be used, and in the stone belt, stones from quarries were used to build walls.

As wall building practice evolved during the 20th century, techniques also changed. From using solid walls as standard, the adoption of a cavity design dividing the wall into an inner and outer wall began to be widely adopted. This meant the inner wall was now responsible for load-bearing duties rather than the thick wooden beams or locally sourced stone of old.

With load-bearing duties taken care of, it was possible to suspend the outer wall from the inner wall for weatherproofing purposes. Insulation could be added between the inner and outer wall to achieve heat retention. Since the outer wall no longer needed to be self-supporting, and now had the sole purpose of keeping weather out, this permitted the use of thinner materials. As a result the choice of surfacing available to housebuilders opened up.

Insulation

Adding insulation to a home requires an application to the local building control department, but when it comes to the cladding itself, Building Regulation approval is not always needed. As long as the home is not in a conservation area, changes can usually be added under permitted development rights.

With today’s weatherboarding choices extending beyond timber, brick, stone and render, housebuilders have more freedom to select and change the outside aesthetic of their home. The availability of modern day alternatives has seen the rise of new timber, High Pressure Laminate (HPL), and fibre cement, to name but three examples.

Modern materials

Timber, an age-old favourite, particularly in Scandinavia, was conventionally stained black or brown when applied as cladding. Easy to install and affordable, the 21st century has seen the adoption of unstained timber such as spruce, cedar and oak as it can last for decades without requiring surface coating, although other surface treatments are needed for the wood to maintain its looks.

One drawback of timber is the limited design choice it offers. Cedar, for example, has become a victim of its own success. It’s become such a popular aesthetic for housing developments in recent years that architects and designers are shunning it in favour of more unusual options.

After timber, fibre cement is the most established material for weatherboarding. Although one of the heavier materials to use for cladding, fibre cement is simple to install and low cost, especially as it can be nailed. Since it can be painted, it is available in a wide choice of colours, although care is needed, as the paint can chip.

In terms of impact resistance, fibre cement can break, so care must be taken around fixings. In addition, cut edges need to be sealed to protect from water ingress.

Robust, lightweight, straightforward to apply and moisture resistant, HPL cladding provides a very cost effective and extremely low maintenance way to improve the look and efficiency of older builds. Transforming old building stock can be easily accomplished, with a fresh, new cladding skin, and the building’s thermal performance can be improved if additional insulation is included into the cladding system design. HPL can also be used to fully clad new builds, or incorporated as part of a design feature alongside materials such as brick, render or glass.

New ‘lap’ weatherboard cladding systems can be bought off the shelf from builder’s merchants to give the look of timber, but without the need for any pre or post-installation treatments. A screw-fixed solution makes it simple for both professionals and semi-professionals to install. Creating sleek builds with clean lines is easy, as the fixings are concealed by the next overlapping plank. In addition, HPL cladding doesn’t need to be painted during its lifetime.

Beyond the facade

Selecting the right cladding for a housebuilding project can significantly improve a build’s cost and property value, not just its aesthetic.

When choosing a cladding solution, it is important to consider how the material will affect the building’s energy efficiency, environmental impact and overall performance. Such measurements cannot be done in isolation as cladding is a system, and so consideration must be given to factors like insulation, thermal performance and the material’s sustainability credentials.

Today’s modern surfaces mean a building’s exterior look is no longer restricted by the materials found in the surrounding environment. The availability of a variety of weatherboard cladding options means performance and aesthetics can be balanced rather than one being sacrificed over the other.

Simon Wild is European category marketing manager at Formica group