House extension materials
Most house extension external materials match the existing property for the walls and roof. This is
usually a requirement of Planning permission and even a condition for permitted development extensions. It is also
quite normal and expected that an extension should match that of the original dwelling. However, it is often
advisable to use contrasting materials instead.
Extending a home will also add to the external visual impact to a property simply by
increasing its mass, volume and bulk. Some home extensions will also impact upon the important street scene so
increasing the buildings visual impact can be an important aspect of any home extension designer or architect and
simply adding matching materials can have a detrimental visual appearance by simply increasing the existing colour
& textures of the existing walls and roof coverings to an unacceptable level.
This impact can often be reduced or mitigated by the clever use of contrasting external materials. If a property
to be extended appears too wide on the plot becoming over dominant for the street scene, utilising a different
walling material for the wall construction for example can help break up & reduce the visual impact.
An example could be using a painted sand / cement rendering for a two storey side extension where the existing
property has a dark red brick. Another example for when an extended property appears too tall or brutal (on a
sloping site for example), having a different walling material for the new & existing first floor element of
the extended property can help horizontally split the property to visually reduce its perceived overbearing
appearance. This could be by having a mix of house extension materials such as black stained timber weather
boarding above facing bricks or a first floor tile hung section over ground floor rendered walls.
Changing the roofing material is a little more difficult as any change can often look odd. Clever design of the
house extension roof to begin with is a better choice for improving the external visual appearance rather than
changing the type of tile or slate.
However, a single storey extension with a mono-pitch lean to roof design could have slates or a interlocking
concrete tile that can go down to a lower roof pitch where the main two storey dwelling house may have a steep
pitched plain tile roof covering for example. This is quite acceptable as there is usually a good separation
between the two types of roof surfaces. Having different roof covering materials for the same or connected roof
slopes can look very odd unless the property is a historic cottage where it was often common to do this (slates
abutting a thatched roof for example).