Open Navigator

walling construction & maintenance

The information contained within these sections are correct at the time of writing, but the frequent updating of the EN and BS codes may mean that construction methods have altered so we suggest that the recommended reading lists and other appropriate codes and standards are considered in the design of the project.

The construction and maintenance sections in this site should be used as a source of information only. It is recommended throughout that specialist advice is sought where required.

Construction

Walling stone for cavity construction should be built similar to a brickwork outer skin. The stone outer wall should be built at the same time as the inner block work leaf, with stainless steel wall ties at appropriate locations. 

For free standing Portland walling the construction can be two skins of walling stones on a solid concrete base and with wall ties to provide additional support. The joints for all walling will vary being typically 10mm to 20mm. The mortar should be: 1 white cement, 2 lime and 8 to 9 Portland Stone Dust.

The design should consider the water management issues with dpcs, cavity trays, weep holes and projecting weathering courses with dip details designed to throw the water off the face of the walling.

Walling can be used in conjunction with sawn quoin blocks, traditional window surrounds and copings manufactured in matching Portland Stone.

Maintenance

It is important to remember that Portland Stone does not normally require cleaning to safeguard its durability, but we recommend that the stonework is inspected on an annual basis to check if any maintenance is required. 

The most common cause of maintenance is defects resulting from water management such as leaking rainwater pipes causing dampness and staining. Cleaning should be with low pressure, clean water and light brushing with a brush with soft bristles.

It is worth noting that split faced and hand dressed walling, due to the textured stone faces, often hold salts and moisture, may be subject to algae growth, particularly in the first couple of years. Some clients may find this an acceptable temporary phenomenon, whilst others may prefer the walling cleaned and the algae controlled.