3.1 Internal & External Corners
Internal corners can be formed by continuing the QT FullMesh around the corner or by embedding a QT CornerMesh into the base coat render. External corners can be formed by embedding a QT CornerMesh into the base coat render or by fixing a corner bead prior to rendering. In all cases the abutting corner panels must be bonded with polyurethane foam adhesive.
3.2 Relief Joints
Relief joints are required to accommodate any structural movement or panel movement due to temperature or moisture changes. If the panel above or below an opening is less than 300mm in depth or more than 2400mm in length the panel must be articulated by creating a vertical expansion joint to reduce and/or relieve the stress in the panel and coating system. All other corner openings must be reinforced with QT 45˚Mesh. The QT 45˚Mesh helps prevent any 45˚hairline cracks forming from the corner of any opening.
3.3 Control joints
Control joints are designed to relieve structural movement between the wall cladding and building frame and also relieve any stress that builds up in the applied coating system. Vertical control joints are required at no greater than 5 metre centres (+ or – 500mm) in walls greater than 8 metres in length. Double studs are required at all vertical control joints. Vertical joints are best aligned with windows, doors, openings, or internal corners. Where timber floor joists are used a 15mm (nom), horizontal control joint must be provided at floor levels to allow for shrinkage and movement of the joists. 10mm control joints must also occur where the QT EcoSeries Wall Panels meet alternative wall claddings eg. Weatherboard, brickwork, etc. On gable ends, a horizontal control joint will be required at the top plate of the wall so as to separate the gable wall from the wall below. Control joints can be formed with the use of a backing rod and sealant or by the installation of uPVC expansion bead.