Facades Flashcards
What is a curtain wall?
A waterproof, non-loadbearing enclosure of window or metal panels in a lightweight framework fixed to the structure of the building.
What defects are associated with curtain walling?
Visual inspection can identify damaged cladding panels, condensation between glazing, cracked glazing, water ingress, air permeability and defective seals/gaskets.
What causes curtain wall defects?
Differential/thermal movement between the cladding and its background. Also cause by poor quality, poor design, poor installation etc.
What are seal/gasket failures?
Poor adhesion, poor cohesion, delamination and reversion.
How can you identify nickle sulphide inclusion in glass?
The glass breaks producing many hexaganol shapes in a butterfly formation - the originof the cracking has two larger fragments that appear in the shape of a butterfly.
What causes the butterfly affect in glass?
When nickle sulphate cools quickly, it stays in its shrunken form. Over time, a volume expansion of the cooling nickel sulphide crystals causes localised tensile stresses and spontaneous breakages of the glass.
