Choosing the right exterior for your home:

Homes can be fabricated with a variety of exterior finishes ranging from brick and stone to stucco, wood, metal and even vinyl. However with global warming looming over our heads, there is a great pressure to select a ‘greener’ option.

Each finish arrives with both advantages and unfortunately some drawbacks, so it can be difficult to determine which the greenest material is. Every manufacturer and supplier have some claim to being environmentally friendly, and a small minority suggesting their products are made of an recycled element which always sounds appealing.

Being seduced by all the marketing hype tends to be the catch 22 between choosing a green material, and choosing a material that is claimed to be environmentally friend. It is important to remember, however, to take a step back and thoroughly scrutinize each aspect of the product before payment methods are discussed. Without doing so, you can easy result in a ‘green washed’ exterior which compromises your homes overall environmental impact.

There are three essential things to consider when it comes to choosing an eco-friendly cladding:

Firstly it is crucial to consider your house as not just a collection of green solutions and features, but rather a system made up of individual elements which need to complement each other in order for your home to work.

The cladding may look visibly appealing, and leave your neighbouring homes in awe, however it may not protect your home as well as it looks. In a wood frame home, the walls are high performance assemblies designed to control heating transfer, air flow as well as water penetration. The exterior finish layer is an integral part of this structure and is much more than just the decorative surface that faces the street. Focusing too much on either the aesthetics or environmental features of a cladding choice, without considering the wall system as a whole, can seriously compromise the overall sustainability of the house.

Secondly you need to consider durability: common sense suggest to us that any exterior finish that wears out prematurely is essentially not environmentally friendly, no matter how much the marketing brochure tells you otherwise.

In particular, newly developed cladding materials should be approached with a certain degree of caution. They may not have the track record to prove that they can stand up to the rigorous 30-40 years of weather and wear. The environmental impact of throwing a worn out cladding system into the landfill and replacing it with a new one after only a few years of use is just too great.

Thirdly climate: it is a subject we are always quick to criticise about daily, nevertheless when it comes to selecting our exterior we are quick to dismiss it. An environmentally sensitive choice of cladding must be driven by the specific climate in which the house is situated, because dry, cold and wet climates all have different requirements.

For instance in a particularly wet climate the exterior cladding should be rainscreen: which means that the finish materials are set off from the wall a slight distance in order to provide a small gap that allows any water that might get behind the outside layer to drain away.

Rainscreen cladding is specifically designed for wet climates, whereas other materials are fixed directly to the structure wall, which in turn traps water inside when the used in a region that has a tendency to have a downpour. The result of using these materials can be moderately serious water damage which compromises the thermal efficiency of the house, as well as trivial but aggravating mould growth which can eventually lead to indoor air quality problems.

In most cases, the negative environmental impact of both of these issues far outweighs the environmental benefits of a cladding system chosen solely on its green features.

Unfortunately there is no simple solution to this painstaking problem, other than being focused and head strong: do not let the sales teams persuade you into purchasing a material which you know in your heart are just not going to cut it.

Focusing too much on the specific environmental features of a particular exterior finish material without considering its integration into the overall wall system, its suitability to the climate in which it is being used, and its overall durability and life-span is like looking at the trees but missing the forest.