“Structural deformation” is common and can be observed in almost every building. Whether the building is under construction or of pre-existing, deformation is sure to creep in almost all structures. Deformations occur at components which are influenced by subsidence, load changes, humidity or even by water level changes.
Deformation of roof structures
Sagging in the roofs is one of the most commonly encountered forms of deformation. Symptoms of a sagged roof are the formation of dish-like shapes or ridges. This sort of structural deformation can be a direct result of any or all of the following.
Pitched roofs
Widespread sagging is mostly visible in the roof coverings which have dished in and have ridge lines bowed over the strutting points and commonly resulting from:-
- Poor design or under design of the roofing together with the spacing, sizing and support
- Overload of the roof framing caused by replacing corrugated iron with terracotta tiles
- Aggressive salt content in the atmosphere in a coastal region
- Incorrect or inadequate support of roof trusses
- Pest damage done to timbers which are unable to support normal load of the roofing
Around Eaves
Localized sagging around the eaves, resulting from excessive cutting of rafters to fit in the wall plates, or excessive removal or cutting of roof framing members for service installation.
Flat Sheet Metal Roofs
Horizontal bending and vertical bowing or even collapse is caused by lack of resistance to vertical pressure of the foundations in the upper floors. Retained earth at the foundation and strong winds working unfavorably are the dual causes.
Deformation of Wall Structures
Horizontal bending and vertical bowing can even lead to a collapse of walls. This is caused due to a lack of resistance in vertical pressures from foundation of roofs or upper floors. There can be horizontal pressures within this stance from both the earth and the wind. This can be the direct result of:-
- Corrosion or rusting of frames or walls
- Inadequate engaged pier stiffness
- Movement and overloading in the function
- Major defect in construction
- Poor design
- Substandard workmanship or materials
- Forces that were previously not accommodated by the initial design.
- Bad workmanship followed by excessive cutting or removal of wall framing timbers for services.
Structural deformation can cause unforeseen damage to any building gradually degrading its stability. It becomes less and less capable of holding on to it base. It is important to thoroughly check for these issues periodically and work to reinstate it to its prior strength.