Design of Portland Stone Façades

Portland Stone has been used for centuries as a building material and these buildings stand as testaments to the stones strength and durability.

There are 5 options for the application of Portland Stone onto building facades.

For information on our Heritage Portland Stone Bricks please see our Landscape section on our Technical Manual

1. Traditional Hand Fixed Cladding

The BS 8298 part 2 covers all aspects of the stone selection, design and installation of traditional external cladding, and it is important that the designer has a copy of this publication for reference.  Some elements of the façade such as copings or pilasters may be covered by the BS EN 12059.

Traditional hand fixed cladding is still widely used for Portland Stone cladding, particularly for the medium and smaller projects. The traditional hand fixed cladding system typically carries the load of the cladding to a load bearing fixing situated at the floor plate. The stones above are simply restrained using Restraint fixings

2. Rainscreen Cladding

The BS 8298 part 4 covers all aspects of the stone selection, design, and installation of stone cladding on rainscreen support systems, and it is important that the designer has a copy of this publication for reference.

Ventilated and drained and pressure-equalised rainscreen cladding are systems of stone cladding in which the stone panels are individually supported and used as part of a system that shields the majority of the supporting structure from direct rainfall. Portland Stone panels can be manufactured at our Portland Factory for incorporation into unitised curtain walling systems.

3. Pre-stressed & Load Bearing Columns (Off-site manufacture)

The BS 8298 codes of practice currently do not specifically cover pre-stressed stone columns or fins, but much of the content is relevant. A number of contracts have been completed, going back to Eric Parry’s building in Finsbury Square in 2002. Albion have the facilities at Portland to be able to assemble the full floor height columns with tensioning cables or bars ready for delivery to site in a jig ready for installation.  Some architects are also re-examining the possibility of reintroducing simply load bearing columns, just using the stones immense compressive strength, back into modern designs. This has very clear environmental advantageous over all other facades.  

4. Strong Backs (Off-site manufacture)

Portland stone strongback system’s steel frame provides an off-site fabrication option for small through to large projects that can be completed at Albion Stone’s Portland factory. The panels are typically full storey height and can perform some structural functions. The stones are normally individually supported and typically open jointed, so BS 8298 part 4 covers the design and installation.

5. Stone on Precast (Off site manufacture)

The BS 8298 part 3 and BS 8297 cover all aspects of the stone selection, design, and installation of natural stone cladding for stone-faced precast concrete cladding, and it is important that the designer has copies of these publications for reference.

The design of the stone on precast differs from other cladding applications as the concrete is attached to the stone so for example, the loading and cavity sections are not part of the stone design. Typically, the stone is designed at 50mm thick, but the option to make it thinner in certain applications can be considered. Ultra-High-Performance Concrete (UHPC) is being considered as a backing structure in place of the traditional precast concrete.


Recommendations for the design, manufacture, installation, and maintenance

Albion Stone, a fourth generation family business pride ourselves on having a helpful and skilled workforce as well as modern and traditional manufacturing process to enable us to produce the highest quality Portland Stone with minimal environmental impact.