Precast Cladding
Architectural Cladding Panels.jpg "Offices - Precast Architectural Cladding Panels - Polished")
Factory produced concrete cladding offers virtually unlimited scope for architectural expression. There is a wide range of high durability, low maintenance surfaces, including both integral and applied finishes. Both highly polished and textured finishes are achievable. Brick, tile, marble and granite are typical finishes, but virtually any decorative stone can be applied. The most cost effective wall panels comprise of reconstituted stone, i.e. naturally coloured, designed and finished to look like natural stone. Panels are typically 150mm thick and may be up to 9m in length and 3.8m high. Panel sizes are generally only limited by transport and cranage constraints.
When installed, cladding panels may be either stacked off the ground, one above the other, thus transferring all vertical loads directly to the ground, or alternatively they may be independently supported at each floor level by means of localised concrete corbels. Lateral fixings are secured to either beams or columns.
The main advantages of precast cladding are:
Tight quality control measures are in place both pre and post casting. Installation is swift and panels are typically sized so that they can span grid to grid and floor to floor, allowing a large area of the building to be weathered in the shortest time possible. No scaffolding is required as all fixings are accessed from the rear of the panels. In most cases, glazing units and insulation may be fitted to the precast units in the factory, speeding up the work of following trades.
To make precast units more cost effective, it is important that panel sizes are maximised and a degree of repetition exists. This approach ensures that a number of panels may be cast from a single mould.
Architectural Wall Panels - Rain Screens.jpg "Office-Precast Cladding Panels - Curved")
Precast wall panels are high strength units which can be quickly installed with little or no site preparation. Natural stone blend, reconstituted stone and terracotta -faced panels are available. Panels arrive on site complete with fixing brackets. The wall is lifted into position and attached to the column which can be either concrete or steel. Connections between floors, beams, columns and wall panels are designed to ensure that all loads, both lateral and vertical, are transferred along the dedicated load path to the appropriate foundation/restraint. Because the loads acting on the panel are transferred into the column, no strip foundation is required. Precast walls can function simply as "security walls"or may act as a bearing for precast floor units.
Architectural Composite Panels
Precast wall panels have been used as rain screens in Ireland for many years. However, Composite Panels are now being manufactured which comprise of an outer leaf of finished concrete (or terracotta tile).jpg "Precast Composite Panel")
, a layer of insulation and a backing leaf of plain grey concrete, cast as a single unit. The insulation is installed under controlled factory conditions and is protected from the elements by the concrete outer leaf. To fully optimise the system, the inner leaf of the sandwich panel can be used as a load-bearing element to support floor units, thus offering further economies in the building and minimising the need for co-ordination of different trades.
Wall panels can eliminate the following on-site activities:
Foundation laying
Block laying
Plastering
