Street: ASHBURNER STREET, MANLY
Bellmont Façade Engineering was engaged by Strata Choice to undertake a visual inspection of the internal cracking occurring within a unit on Ashburner Street, Manly. This inspection was undertaken on Wednesday 21st November 2018.
It was concluded that the internal cracking was likely caused by the weight of bricks that hold down what are called tie down supports. Such supports secure the roof and provide resistance against wind uplift. In this unit, strong multi-directional winds caused movement of the tie down supports which ultimately caused the horizontal cracking within brickwork.
Alternatively, the cracking could’ve also been a result of the corrosion of steel elements, a.k.a. ‘rust jacking’, where the displacement of building elements occurs due to the expansion of steel.
Subsequent to our inspection we would broadly recommend the following:
- Inspection of the remaining upper level units of the complex to ascertain whether similar cracking is visible on the interior rendered & exterior brick walls (where access is provided).
- Creation of a series of investigation holes in the walls (from inside the occupancy) to facilitate use of a bore scope camera to view the condition of brick ties and tie down plates or straps used and assess the level of deterioration.
The scope of works referred to within this technical specification is applicable to the façade of the building, the rooftop and internal works and includes:
Item A: Rooftop Repairs
Item B: Embedded Steel Fixing Removals
Item C: Steel support Beam Replacement
Item D: Steel Pillar Treatment
In solving these suspected issues Bellmont delivered the installation of new gutter brackets along the perimeter of the rooftop, removal of corroded pre-existing mild steel fixings, installation of new sheeting and flashings for skylight including complete weatherproofing, installed new sheeting accommodating existing vents and complete weatherproofing, as well as treatment of the steel pillars.