Civil Engineering Reference
In-Depth Information
15
Surface materials
The main purpose of surface materials is to form a protective layer around a
building's structure. Through hardness and durability they must withstand
wear and tear on the building, from the hard driving rain on the roof to the
never-ending wandering of feet on the floor. Sheet materials can also have struc-
tural and climatic functions such as bracing, wind-proofing, moisture control,
etc. Certain structures in brick, concrete and timber can have the same function
as surface materials and therefore do not need them. Surface materials are other-
wise used in roof covering, internal and external cladding, and on floors.
Because surface materials are used on large, exposed areas, it is important to
choose materials that do not contain environmentally-contaminating substances
which may wash into the soil or groundwater or emit irritating gases into the
interior of the building. They should be both physically and chemically stable
during the whole of their life span in the building or at least be easy to renew.
The roof of the building is its hat. The roof has to protect the building from
everything coming from above, which sets requirements for how it is anchored,
drained, and protected from frost, snow and ice. Most roof materials are used on
the assumption that there is a material beneath them which helps to waterproof
the building.
The external cladding has a similar task in many ways, but the demands are
not as high, especially as far as waterproofing is concerned. In areas of hard rain
and strong winds, durable materials are required.
Internal cladding has lower demands on it in terms of moisture and durabili-
ty. The most critical factor is damage caused by the inhabitants of the building.
Materials in ceilings do not need to have the same high standard as those in the
walls. Internal surfaces should also have a higher level of finish to give a feeling
of comfort and be pleasant to the touch. Cleaning should also be easier with these
finishes. Thin layers such as wallpaper, stainless steel or hessian need a strong
material to adhere to, but this material does not have to be of such a high quali-
ty. This is also the case with painted surfaces.
